Presentation on theme: "GREEN ENERGY KOMPENDIUM KAJIAN LINGKUNGAN DAN PEMBANGUNAN"— Presentation transcript:
1 GREEN ENERGY KOMPENDIUM KAJIAN LINGKUNGAN DAN PEMBANGUNAN Dikoleksi oleh:Sandra, Arief Boediono, Eko Nuryono, dan SoemarnoPDKLP-PPSUB Mei 2012
2 ENERGI HIJAUKriteria Energi Hijau Sebagai Energi Alternatif Energi yang telah banyak diupayakan oleh manusia selain batubara, minyak bumi dan panas bumi dan air, ada juga energi surya, angin dan lain-lain. Energi alternatif yang lagi hangat dibahas pada tingkat nasional maupun internasional adalah energi biodisel (energi bahan bakar nabati-BBN) dan biomassa. Walau sebenarnya kami yakini energi biodisel dan apalagi biomassa sudah sejak dahulu kala ditemukan dan bahkan sudah diaplikasikan dalam kehidupan masyarakat sehari-hari termasuk masyarakat di negara kita. Apa yang dimaksud energi alternatif? Energi alternatif dalam budaya Revolusi Lingkungan adalah energi yang ramah lingkungan yang disebut juga energi hijau. Energi dari biodisel dan biomassa adalah energi hijau dan beberapa kriteria energi hijau sebagai alternatif yang telah kami kumpulkan dari beberapa sumber dan ditambah dengan pemikiran kami adalah sebagai berikut:Energi alternatif harus tidak menghasilkan emisi karbon yang akan menyebabkan pemanasan global, dalam hal ini energi nuklir tidak termasuk walau diketahui tidak menghasilkan emisi karbon tetapi sekali lagi kami mempunyai pandangan lain dan menentang keras pemakaian dan pemanfaatan energi nuklir untuk kehidupan sehari-hari manusia kecuali untuk penelitian. Baca dan dengarkan suara kami mengapa harus nuklir?Energi alternatif tidak mengakomodasi sumber tanaman pangan atau tanaman pertanian penting yang dijadikan kebutuhan pokok dan tambahan pada sekelompok orang atau budaya tertentu sebagai penghasil energi. Karena menurut kami ranah energi banyak terkandung isu strategis dan politis suatu negara dan kawasan Walau dari segi jenis komoditas dan varitas tanaman sudah memenuhi, energi alternatif juga tidak memberikan ancaman konversi pemakaian lahan pertanian yang berlebihan, karena bagaimanapun dibelahan sudut manapun di dunia semua manusia membutuhkan energi yang sama sehingga dari aspek ekonomi pasti lebih menguntungkan apalagi kalau mengkonversi lahan pertanian tradisional yang sudah menjadi tradisi turun temurunEnergi alternatif tidak dihasilkan dengan menghasilkan masalah baru misal merubah kawasan hutan yang seharusnya sebagai penyanggah paru-paru dunia malah menjadi bisnis pertanian biodiselSumber: Diunduh 5/5/2012.
3 GREEN ENERGYGreen energy is energy that is produced in a manner that has less of a negative impact to the environment than energy sources like fossil fuels, which are often produced with harmful side effects. “Greener” types of energy that often come to mind are solar, wind, geothermal and hydro energy. There are several more, even including nuclear energy, that is sometimes considered a green energy source because of its lower waste output relative to energy sources such as coal or oil.The goal of green energy is generally to create power with as little pollution as possible produced as a by-product. Every form of energy collection will result in some pollution, but those that are green are known to cause less than those that are not. Most people who advocate greener sources of energy claim that the result of worldwide use of green energy will result in the ability to preserve the planet for a longer time. Greenhouse gases, a by-product of traditional sources of energy such as fossil fuels are thought to be causing global warming, or the process of the Earth heating up at an accelerated pace.Renewable green energy is energy that comes from renewable sources, and lowers overall air pollution or negative environmental effects. Renewable energy is defined as energy coming from infinite sources rather than finite physical or commodity sources. Green energy is commonly defined as energy that lowers a negative impact by decreasing outgoing emissions of toxins like carbon dioxide and greenhouse gases. The collective term “renewable green energy” puts these two criteria together. Since the multiple criteria are in many ways complementary, renewable green energy represents the ideal choice for a range of government and business uses, as well as mass residential usage.Diunduh dari:Sumber: Diunduh 5/5/2012
4 Some of the main examples of renewable green energy include solar energy, wind energy, and hydropower or water generated energy. Other more obscure forms of energy that some call renewable and green are biomass energies, although experts could argue that these are actually finite sources, due to the necessary fertile land for production of the products that are used. Some common examples of non-renewable energies are fossil fuels. Coal and oil are the two main non-renewable energies that power much of the world’s energy use. Governments and businesses all over the world are trying to find renewable green energy solutions that will replace non-renewable or unsustainable polluting energy sources.In very basic terms, the appeal of renewable green energy is that the sources of this energy are not depleted. Solar power does not deplete the force of the sun, and wind or water power do not deplete the force of moving air or water. Likewise, these various forms of energy production do not result in the output of various volatile gases and particles that are hazardous to human and environmental health. Considering renewable green energy sources has become more important as the world’s population grows rapidly, and the total energy use of various nations increases on a seemingly exponential plane.Another consideration with renewable green energy is different methods for different uses. Renewable energy sources might be used to provide electricity for a grid, which is possible with solar and wind power. Renewable energies could also be used to heat a home or other building, where methods for generating these energies might be different, since such a high amount of energy is typically needed for heating and cooling. One innovative solution for renewable green heating is geothermal application. In these types of setups, the temperature of an interior space is controlled by water or other materials run through various conduits underneath the building at specific temperatures.Diunduh dari:Sumber: Diunduh 5/5/2012
5 . Types of Green Energy. Green energy is created from natural resources that do not cause harmful pollution to Earth's surface or atmosphere. With the concern of global warming and depleting natural resources, environmentally friendly alternatives are needed. Earth's sun, water and wind power have been used to operate machinery and generate power since ancient times. This article describes the different types of green energy that are currently being considered as alternative sources of power.Read more: Types of Green Energy | eHow.comHydropowerHydropower converts water from rivers into usable energy released from turbines. Before commercial electric power, it was used for irrigation and operation of machinery. Water wheels and mills produced flour from grain and sawing stone and wood. Today, it is considered very expensive and difficult to build hydropower plants to produce mass amounts of electricity. There are also concerns that their usage may affect wildlife and change the quality of the water.Read more: Types of Green Energy | eHow.comGeothermalGeothermal energy is produced from steam or hot water from under the Earth's surface. The steam powers electric generators by rotating turbines. One use for it is heating buildings. It is not widely available due to the lack of natural land sites. There are also concerns that geothermic fields may eventually deplete. The largest sites are in California, called the "Geysers." It is a green energy due to its low emissions. Its production is not affected by weather changes and can continuously work day and night. There are also some concerns about geothermal fields affecting the surrounding land's stability.Read more: Types of Green Energy | eHow.comSumber: …. Diunduh 5/5/2012
6 Diunduh dari: http://www.greenenergy.uk.com/TypesOfGreenEnergy.aspx WindWind can be used to create energy by rotating large propellers like blades around a hub. The blades slow down the speed of the wind it captures and channels it to a generator that produces electricity. Wind energy usage worldwide is very small; the technology is expensive and its machinery is considered to be noisy. The few wind energy companies that produce electricity are privately owned and sell their electricity to public utilities. The energy it produces generates no pollution and has been used to power homes, farms and ranches.Read more: Types of Green Energy | eHow.comSolarSolar is another form of green energy. Photovoltaic cells can absorb light from the sun to capture electrons and use them to generate electricity. The sun has been used as a source of energy since ancient times. It gained some popularity after the energy crisis of However, it is still considered to be expensive due the cost to produce the photovoltaic celled panels needed to generate energy. These types panels are usually large and take up a lot of space. Solar energy is also inconsistent and needs a large surface area to generate enough electricity on a large scale. Despite its setbacks, solar energy is being used to power some homes, cars and in agriculture.Read more: Types of Green Energy | eHow.comAnaerobic digestion – a process where microorganisms break down organic material without any oxygen – produces a methane- and carbon dioxide-rich biogas. This can be burnt to produce energy, with none of the harmful effects of fossil fuels. And what's more, the nutrient-rich solids left after digestion can be handily used as a fertiliser!Diunduh dari:Sumber: …. Diunduh 5/5/2012
7 WHAT IS GREEN ENERGY ?Biomass is produced from organic material – that's wood, plants and animal waste to you and me. We get this either directly from plants, or from waste products from industry, agriculture or your very own home!Biomass falls into two categories: Wood biomass includes forest products, waste wood and energy crops like elephant grass and quick-growing trees like willow. We buy energy created from burning waste wood.Non-wood biomass includes animal waste and biodegradable food products like vegetable oil.Diunduh dari:SUMBER: ….. DIUNDUH 10/3/2012
8 BiomassBiomass energy is produced from organic materials such as plants and animals, but the energy that is produced in this fashion is originally provided by the sun. For example, plants absorb the sun’s energy through a process called photosynthesies. This energy is then passed on through the organism that eats the plant, creating biomass energy. The most common forms used to generate biomass energy are wood, crops, manure and some rubbish.When these substances are burned, they give off energy as heat. For example, if you have a wood fuelled heating, you are generating renewable biomass energy. This is not the only method of generating biomass energy; you can also create biomass energy by converting these substances into methane gases, ethanol and biodiesel fuels which can be translated more easily into our current methods of energy use.BiofuelsBiofuels are a form of renewable energy derived from burning plant or animal substances, otherwise called combustion. One of the challenges to biofuels has been that it is not easily transferred into a liquid form which is the primary method used to fuel most cars and homes. Two of the most common strategies that are sed to produce biofuels includes: growing crops to produce ethanol and growing plants that produce biofuel oils. While these methods are effective sources of renewable energy, they are challenging to produce and maintain on a large scale.WindAn abundant source of renewable energy, wind power is used as a means of generating electricity. Wind turbines are capable of harnessing the power derived from the wind, converting kinetic energy into mechanical energy. A source of clean, green renewable energy, favourable climate conditions in Europe means wind energy is a highly viable method for electricity generation. And none more so than in the UK, with 40% of all wind energy in Europe blowing over the country.Sumber: …. Diunduh 5/5/2012
9 Green energy, or renewable energy, is the use of sustainable, pollutant-free resources that benefit the environment by reducing overall waste production. By practicing green techniques in the home, people can reduce their gas and electricity consumption.There are several types of green energy, all of which work in specific ways to positively impact the planet and save consumers money by reducing the cost and necessity of fossil fuels to produce electricity.How Green Energy WorksSolar energy harnesses radiation from the sun, converting sunlight into electricity through the use of photovoltaic cell devices, large mirrors, or lenses.Wind energy, or the energy of air in motion, can be converted into mechanical energy that generates electricity through the use of wind turbines.Water energy, or hydropower, is the practice of converting flowing water into mechanical energy through the use of penstock piping. Electricity is then derived from mechanical energy through use of a generator.Biomass energy, which can be produced from substances such as garbage, cow manure and wood, involves the burning of biomass fuel in boilers. This type of energy can be used in steam turbines to create electricity and can be used to heat water.Geothermal energy is generated underground through the trapping of heat. When the heat rises to the land surface, it is harnessed as steam and used in steam turbines to produce electricity.Sumber: …. Diunduh 5/5/2012
12 RENEWABLE GREEN ENERGY Renewable green energy comes from green sources of energy. These sources are usually harnessed with little pollution. Geothermal power, wind, wave and solar power are some of the renewable green energy sources that are known today. Here we will describe all the kinds of renewable green energy sources currently in use and the efficiency and scale of these sources.We will look at what’s the best solution for our future energy demands. Will it depend on only one source of energy or will there be a wide range of energy sources we should use instead of the current polluting sources of energy?
13 ENERGY CONSERVATIONEnergy conservation is the practice of decreasing the quantity of energy used. It may be achieved through efficient energy use, in which case energy use is decreased while achieving a similar outcome, or by reduced consumption of energy services. Energy conservation may result in increase of financial capital, environmental value, national security, personal security, and human comfort.Individuals and organizations that are direct consumers of energy may want to conserve energy in order to reduce energy costs and promote economic security.Industrial and commercial users may want to increase efficiency and thus maximize profit.
14 ELECTRICAL ENERGY CONSERVATION Electrical energy conservation is an important element of energy policy.Energy conservation reduces the energy consumption and energy demand per capita, and thus offsets the growth in energy supply needed to keep up with population growth. This reduces the rise in energy costs, and can reduce the need for new power plants, and energy imports. The reduced energy demand can provide more flexibility in choosing the most preferred methods of energy production.By reducing emissions, energy conservation is an important part of lessening climate change. Energy conservation facilitates the replacement of non-renewable resources with renewable energy.Energy conservation is often the most economical solution to energy shortages, and is a more environmentally benign alternative to increased energy production.
15 Issues with energy conservation Critics and advocates of some forms of energy conservation make the following arguments:Standard economic theory suggests that technological improvements that increase energy efficiency will tend to increase, rather than reduce energy use. This is called the Jevons Paradox and it is said to occur in two ways.Firstly, increased energy efficiency makes the use of energy relatively cheaper, thus encouraging increased use.Secondly, increased energy efficiency leads to increased economic growth, which pulls up energy use in the whole economy. This does not imply that increased fuel efficiency is worthless. Increased fuel efficiency enables greater production and a higher quality of life(Wackernagel, Mathis and William Rees, 1997, "Perpetual and structural barriers to investing in natural capital: economics from an ecological footprint perspective." Ecological Economics, Vol.20 No.3 p3-24).Energy efficiency may refer to:Efficient energy use, sometimes simply called energy efficiency.Energy conversion efficiency, the ratio between the output and input of an energy conversion machine.Energy conservation, efforts made to reduce energy consumption.
16 (Best Buy Optimas Award Winner for 2007). OVER-ILLUMINATIONSome retailers argue that bright lighting stimulates purchasing. Health studies have demonstrated that headache, stress, blood pressure, fatigue and worker error all generally increase with the common over-illumination present in many workplace and retail settings (Davis, 2001), (Bain, 1997). It has been shown that natural daylighting increases productivity levels of workers, while reducing energy consumption.(Lumina Technologies Inc., Santa Rosa, Ca., Survey of 156 California commercial buildings energy use, August, 1996).The use of telecommuting by major corporations is a significant opportunity to conserve energy, as many Americans now work in service jobs that enable them to work from home instead of commuting to work each day(Best Buy Optimas Award Winner for 2007).
17 ELECTRIC MOTORElectric motors consume more than 60% of all electrical energy generated and are responsible for the loss of 10 to 20% of all electricity converted into mechanical energy(European Commission of the Institute for Environment and Sustainability, "Electricity Consumption and Efficiency Trends in the Enlarged European Union 2006)Consumers are often poorly informed of the savings of energy efficient products.The research one must put into conserving energy often is too time consuming and costly when there are cheaper products and technology available using today's fossil fuels.Sumber: diunduh 8/3/2012
18 Its editor-in-chief since 1996 is Sonja Boehmer-Christiansen. E & E JOURNALEnergy & Environment (E&E) is a peer-reviewed academic journal aimed at natural scientists, technologists, and the international social science and policy communities covering the direct and indirect environmental impacts of energy acquisition, transport, production and use.Its editor-in-chief since 1996 is Sonja Boehmer-Christiansen.Contributors have included David Henderson, Richard Tol, and Gary Yohe."Social Sciences Citation Index". Thomson Reuters. Retrieved"Environment Complete: Database Coverage List". EBSCO. Retrieved
19 ENERGY CONSERVATION ISSUES DAMPAK LINGKUNGANThe environmental impact of the energy industry is diverse.Energy has been harnessed by humans for millennia. Initially it was with the use of fire for light, heat, cooking and for safety, and its use can be traced back at least 1.9 million years.In recent years there has been a trend towards the increased commercialization of various renewable energy sources.ENERGY CONSERVATION ISSUESThe use of telecommuting by major corporations is a significant opportunity to conserve energy, as many Americans now work in service jobs that enable them to work from home instead of commuting to work each day.Electric motors consume more than 60% of all electrical energy generated and are responsible for the loss of 10 to 20% of all electricity converted into mechanical energy (European Commission of the Institute for Environment and Sustainability, "Electricity Consumption and Efficiency Trends in the Enlarged European Union ", 2006).Consumers are often poorly informed of the savings of energy efficient products. The research one must put into conserving energy often is too time consuming and costly when there are cheaper products and technology available using today's fossil fuels(The Difficulties of Energy Efficiency. "The Elusive Negawatt ", 2008).
20 (Renewable Energy Policy Network for the 21st Century) Renewable energy is energy which comes from natural resources such as sunlight, wind, rain, tides, and geothermal heat, which are renewable (naturally replenished). About 16% of global final energy consumption comes from renewables, with 10% coming from traditional biomass, which is mainly used for heating, and 3.4% from hydroelectricity.New renewables (small hydro, modern biomass, wind, solar, geothermal, and biofuels) accounted for another 3% and are growing very rapidly (.The share of renewables in electricity generation is around 19%, with 16% of global electricity coming from hydroelectricity and 3% from new renewables.(Renewable Energy Policy Network for the 21st Century)
21 RENEWABLE ENERGYRenewable energy flows involve natural phenomena such as sunlight, wind, tides, plant growth, and geothermal heat, as the International Energy Agency explains:Renewable energy is derived from natural processes that are replenished constantly. In its various forms, it derives directly from the sun, or from heat generated deep within the earth.Included in the definition is electricity and heat generated from solar, wind, ocean, hydropower, biomass, geothermal resources, and biofuels and hydrogen derived from renewable resources.IEA Renewable Energy Working Party (2002). Renewable Energy... into the mainstream, p. 9.
22 RENEWABLE ENERGYRenewable energy replaces conventional fuels in four distinct areas:electricity generation, hot water/ space heating, motor fuels, and rural (off-grid) energy services.Renewable energy is energy which comes from natural resources such as sunlight, wind, rain, tides, and geothermal heat, which are renewable (naturally replenished). About 16% of global final energy consumption comes from renewables, with 10% coming from traditional biomass, which is mainly used for heating, and 3.4% from hydroelectricity. New renewables (small hydro, modern biomass, wind, solar, geothermal, and biofuels) accounted for another 3% and are growing very rapidly.The share of renewables in electricity generation is around 19%, with 16% of global electricity coming from hydroelectricity and 3% from new renewables.. REN21 (2010). Renewables 2010 Global Status Report p. 15.
23 PEMBANGKIT ENERGIRenewable energy provides 19% of electricity generation worldwide. Renewable power generators are spread across many countries, and wind power alone already provides a significant share of electricity in some areas: for example, 14% in the U.S. state of Iowa, 40% in the northern German state of Schleswig-Holstein, and 20% in Denmark.Some countries get most of their power from renewables, including Iceland and Paraguay (100%), Norway (98%), Brazil (86%), Austria (62%), New Zealand (65%), and Sweden (54%).REN21 (2010). Renewables 2010 Global Status Report p. 53.
24 PEMANAS DAN PENGHANGAT Solar hot water makes an important contribution to renewable heat in many countries, most notably in China, which now has 70% of the global total (180 GWth).Most of these systems are installed on multi-family apartment buildings and meet a portion of the hot water needs of an estimated 50–60 million households in China. Worldwide, total installed solar water heating systems meet a portion of the water heating needs of over 70 million households.The use of biomass for heating continues to grow as well. In Sweden, national use of biomass energy has surpassed that of oil. Direct geothermal for heating is also growing rapidly.REN21 (2010). Renewables 2010 Global Status Report p. 53.
25 REN21 (2010). Renewables 2010 Global Status Report p. 53. TRANSPORT FUELS.Renewable biofuels have contributed to a significant decline in oil consumption in the United States since 2006.The 93 billion liters of biofuels produced worldwide in 2009 displaced the equivalent of an estimated 68 billion liters of gasoline, equal to about 5% of world gasoline production.Biofuels provided 3% of the world's transport fuel in Mandates for blending biofuels exist in 31 countries at the national level and in 29 states/provinces. According to the International Energy Agency, biofuels have the potential to meet more than a quarter of world demand for transportation fuels by 2050.Since the 1970s, Brazil has had an ethanol fuel program which has allowed the country to become the world's second largest producer of ethanol (after the United States) and the world's largest exporter.Brazil’s ethanol fuel program uses modern equipment and cheap sugarcane as feedstock, and the residual cane-waste (bagasse) is used to produce heat and power.There are no longer light vehicles in Brazil running on pure gasoline. By the end of 2008 there were 35,000 filling stations throughout Brazil with at least one ethanol pump.REN21 (2010). Renewables 2010 Global Status Report p. 53.
26 WIND POWERAirflows can be used to run wind turbines. Modern wind turbines range from around 600 kW to 5 MW of rated power, although turbines with rated output of 1.5–3 MW have become the most common for commercial use; the power output of a turbine is a function of the cube of the wind speed, so as wind speed increases, power output increases dramatically.Globally, the long-term technical potential of wind energy is believed to be five times total current global energy production, or 40 times current electricity demand. This could require wind turbines to be installed over large areas, particularly in areas of higher wind resources. Offshore resources experience average wind speeds of ~90% greater than that of land, so offshore resources could contribute substantially more energyEWEA Executive summary "Analysis of Wind Energy in the EU-25" (PDF). European Wind Energy Association.
27 WIND POWERAreas where winds are stronger and more constant, such as offshore and high altitude sites, are preferred locations for wind farms.Typical capacity factors are 20-40%, with values at the upper end of the range in particularly favourable sites.Wind power is the conversion of wind energy into a useful form of energy, such as using wind turbines to make electricity, windmills for mechanical power, windpumps for water pumping or drainage, or sails to propel ships.The total amount of economically extractable power available from the wind is considerably more than present human power use from all sources.At the end of 2011, worldwide nameplate capacity of wind-powered generators was 238 gigawatts (GW), growing by 41 GW over the preceding year.Wind power now (2010 data) has the capacity to generate 430 TWh annually, which is about 2.5% of worldwide electricity usage(World Wind Energy Report 2010" (PDF). Report. World Wind Energy Association. FebruaryHow Does A Wind Turbine's Energy Production Differ from Its Power Production?[dead link] ^ Wind Power: Capacity Factor, Intermittency, and what happens when the wind doesn’t blow?.
28 A wind farm may also be located offshore. WIND POWERGlobally, the long-term technical potential of wind energy is believed to be five times total current global energy production, or 40 times current electricity demand.This could require wind turbines to be installed over large areas, particularly in areas of higher wind resources. Offshore resources experience average wind speeds of ~90% greater than that of land, so offshore resources could contribute substantially more energy.A wind farm is a group of wind turbines in the same location used for production of electric power. A large wind farm may consist of several hundred individual wind turbines, and cover an extended area of hundreds of square miles, but the land between the turbines may be used for agricultural or other purposes.A wind farm may also be located offshore.Many of the largest operational onshore wind farms are located in the US. As of November 2010, the Roscoe Wind Farm is the largest onshore wind farm in the world at MW, followed by the Horse Hollow Wind Energy Center (735.5 MW). As of November 2010, the Thanet Wind Farm in the UK is the largest offshore wind farm in the world at 300 MW, followed by Horns Rev II (209 MW) in Denmark."Offshore stations experience mean wind speeds at 80 m that are 90% greater than over land on average. Evaluation of global wind power
29 Sumber: http://ga.water.usgs.gov/edu/wuhy.html …… diunduh 8/3/2012 HYDROPOWEREnergy in water can be harnessed and used. Since water is about 800 times denser than air, even a slow flowing stream of water, or moderate sea swell, can yield considerable amounts of energy. There are many forms of water energy:Hydroelectric energy is a term usually reserved for large-scale hydroelectric dams. Examples are the Grand Coulee Dam in Washington State and the Akosombo Dam in Ghana.Micro hydro systems are hydroelectric power installations that typically produce up to 100 kW of power. They are often used in water rich areas as a remote-area power supply (RAPS).Run-of-the-river hydroelectricity systems derive kinetic energy from rivers and oceans without using a dam.Sumber: …… diunduh 8/3/2012
30 SOLAR ENERGYSolar energy is the energy derived from the sun through the form of solar radiation. Solar powered electrical generation relies on photovoltaics and heat engines. A partial list of other solar applications includes space heating and cooling through solar architecture, daylighting, solar hot water, solar cooking, and high temperature process heat for industrial purposes.Solar technologies are broadly characterized as either passive solar or active solar depending on the way they capture, convert and distribute solar energy. Active solar techniques include the use of photovoltaic panels and solar thermal collectors to harness the energy. Passive solar techniques include orienting a building to the Sun, selecting materials with favorable thermal mass or light dispersing properties, and designing spaces that naturally circulate air.Sumber: diunduh 8/3/2012
31 BIOMASSBiomass (plant material) is a renewable energy source because the energy it contains comes from the sun. Through the process of photosynthesis, plants capture the sun's energy. When the plants are burnt, they release the sun's energy they contain. In this way, biomass functions as a sort of natural battery for storing solar energy. As long as biomass is produced sustainably, with only as much used as is grown, the battery will last indefinitely.In general there are two main approaches to using plants for energy production: growing plants specifically for energy use (known as first and third-generation biomass), and using the residues (known as second-generation biomass) from plants that are used for other things.Union of Concerned Scientists. How Biomass Energy Works
32 Biofuels provided 2.7% of the world's transport fuel in 2010. Biofuels include a wide range of fuels which are derived from biomass. The term covers solid biomass, liquid fuels and various biogases.Liquid biofuels include bioalcohols, such as bioethanol, and oils, such as biodiesel. Gaseous biofuels include biogas, landfill gas and synthetic gas.Bioethanol is an alcohol made by fermenting the sugar components of plant materials and it is made mostly from sugar and starch crops. With advanced technology being developed, cellulosic biomass, such as trees and grasses, are also used as feedstocks for ethanol production. Ethanol can be used as a fuel for vehicles in its pure form, but it is usually used as a gasoline additive to increase octane and improve vehicle emissions. Bioethanol is widely used in the USA and in Brazil.Biodiesel is made from vegetable oils, animal fats or recycled greases. Biodiesel can be used as a fuel for vehicles in its pure form, but it is usually used as a diesel additive to reduce levels of particulates, carbon monoxide, and hydrocarbons from diesel-powered vehicles. Biodiesel is produced from oils or fats using transesterification and is the most common biofuel in Europe.Biofuels provided 2.7% of the world's transport fuel in 2010.REN21 (2011). "Renewables 2011: Global Status Report". pp. 13–14.
33 GEOTHERMAL ENERGYGeothermal energy is thermal energy generated and stored in the Earth. Thermal energy is the energy that determines the temperature of matter. Earth's geothermal energy originates from the original formation of the planet (20%) and from radioactive decay of minerals (80%). The geothermal gradient, which is the difference in temperature between the core of the planet and its surface, drives a continuous conduction of thermal energy in the form of heat from the core to the surface. The adjective geothermal originates from the Greek roots geo, meaning earth, and thermos, meaning heat.The heat that is used for geothermal energy can be stored deep within the Earth, all the way down to Earth’s core – 4,000 miles down. At the core, temperatures may reach over 9,000 degrees Fahrenheit. Heat conducts from the core to surrounding rock. Extremely high temperature and pressure cause some rock to melt, which is commonly known as magma. Magma convects upward since it is lighter than the solid rock. This magma then heats rock and water in the crust, sometimes up to 700 degrees Fahrenheit.Nemzer, J. "Geothermal heating and cooling".
34 BIOFUELS FOR TRANSPORTATION Biofuels provided 3% of the world's transport fuel in Mandates for blending biofuels exist in 31 countries at the national level and in 29 states/provinces.According to the International Energy Agency, biofuels have the potential to meet more than a quarter of world demand for transportation fuels by 2050.Since the 1970s, Brazil has had an ethanol fuel program which has allowed the country to become the world's second largest producer of ethanol (after the United States) and the world's largest exporter.Brazil’s ethanol fuel program uses modern equipment and cheap sugarcane as feedstock, and the residual cane-waste (bagasse) is used to produce heat and power.There are no longer light vehicles in Brazil running on pure gasoline. By the end of 2008 there were 35,000 filling stations throughout Brazil with at least one ethanol pump.Daniel Budny and Paulo Sotero, editor ( ). "Brazil Institute Special Report: The Global Dynamics of Biofuels" (PDF). Brazil Institute of the Woodrow Wilson Center. Retrieved
35 The central role of photosynthesis in bio-fuel production. Photosynthesis plays an absolutely central role in all bio-fuel production processes as it is the first step in the conversion of solar energy (light) to chemical energy and therefore ultimately responsible for driving the production of the feed stocks required for fuel synthesis :protons & electrons (for bio-H2), sugars & starch (for bio-ethanol), oils (for bio-diesel) and biomass (for BTL & bio-methane). Consequently, any increase in photosynthetic efficiency will enhance the competitiveness of bio-fuel production in general.Sumber: ….. Diunduh 9/3/2012
36 ARTIFICIAL PHOTOSYNTHESIS Artificial photosynthesis uses techniques include nanotechnology to store solar electromagnetic energy in chemical bonds by splitting water to produce hydrogen and then using carbon dioxide to make methanol.Artificial photosynthesis is a chemical process that replicates the natural process of photosynthesis, a process that converts sunlight, water, and carbon dioxide into carbohydrates and oxygen.The term is commonly used to refer to any scheme for capturing and storing the energy from sunlight in the chemical bonds of a fuel (a solar fuel).Photocatalytic water splitting converts water into protons (and eventually hydrogen) and oxygen, and is a main research area in artificial photosynthesis. Light-driven carbon dioxide reduction is another studied process, replicating natural carbon fixation.Collings AF and Critchley C (eds). Artificial Photosynthesis- From Basic Biology to Industrial Application (Wiley-VCH Weinheim 2005) p ix.
37 PHOTOSYNTHETIC REACTION The photosynthetic reaction can be divided into two half-reactions (oxidation and reduction), both of which are essential to producing fuel. In plant photosynthesis, water molecules are photo-oxidized to release oxygen and protons.The second stage of plant photosynthesis (also known as the Calvin-Benson cycle) is a light-independent reaction that converts carbon dioxide into glucose.Researchers of artificial photosynthesis are developing photocatalysts to perform both of these reactions separately.Furthermore, the protons resulting from water splitting can be used for hydrogen production.These catalysts must be able to react quickly and absorb a large percentage of solar photons.
38 FOTO-VOLTAIKWhereas photovoltaics can provide direct electrical current from sunlight, the inefficiency of fuel production from photovoltaic electricity (indirect process) and the fact sunshine is not constant throughout time sets a limit to its use.A way of using natural photosynthesis is via the production of biofuel through biomass, also an indirect process that suffers from low energy conversion efficiency (due to photosynthesis' own low efficiency in converting sunlight to biomass), and clashes with the increasing need of land mass for human food production.Artificial photosynthesis aims then to produce a fuel from sunlight that can be stored and used when sunlight is not available, by using direct processes, that is, to produce a solar fuel. With the development of catalysts able to reproduce the key steps of photosynthesis, water and sunlight would ultimately be the only needed sources for clean energy production. The only by-product would be oxygen, and production of a solar fuel has the potential to be cheaper than gasoline.
39 PHOTOCATALYTIC WATER SPLITTING One process for the creation of a clean and affordable energy supply is the development of photocatalytic water splitting under solar light. This method of sustainable hydrogen production is a key objective in the development of alternative energy systems of the future.It is also predicted to be one of the more, if not the most, efficient ways of obtaining hydrogen from water.The conversion of solar energy into hydrogen via a water-splitting process assisted by photosemiconductor catalysts is one of the most promising technologies in development. This process has the potential for large quantities of hydrogen to be generated in an ecologically sound method.The conversion of solar energy into a clean fuel (H2) under ambient conditions is one of the greatest challenges facing scientists in the twenty-first century.
40 SOLAR FUEL CELLSTwo approaches are generally recognized in the construction of solar fuel cells for hydrogen production:A homogeneous system is one where catalysts are not compartmentalized, that is, components are present in the same compartment. This means that hydrogen and oxygen are produced in the same location. This can be a drawback, since they compose an explosive mixture, demanding further gas purification. Also, all components must be active in approximately the same conditions (e.g., pH).A heterogeneous system has two separate electrodes, an anode and a cathode, making possible the separation of oxygen and hydrogen production.Furthermore, different components do not necessarily need to work in the same conditions. However, the increased complexity of these systems makes them harder to function and they are more costly.
41 ARTIFICIAL PHOTOSYNTHESIS CURRENT RESEARCH:ARTIFICIAL PHOTOSYNTHESISIn energy terms, natural photosynthesis can be divided in three steps:Light harvesting by antennae complexes, that capture photons and transduce them into electrons, injecting them into the photosynthetic chain.Proton-coupled electron transfer along several cofactors of the photosynthetic chain, causing local, spatial charge separation.Redox catalysis, which uses the aforementioned transferred electrons, to oxidize water to dioxygen and protons; these protons can in some species be utilized for dihydrogen production.A triad assembly, with a photosensitizer (P) linked in tandem to a water oxidation catalyst (D) and a hydrogen evolving catalyst (A). Electrons flow from D to A when catalysis occurs.
42 The oxidized donor is able to perform water oxidation. BIOMIMETICUsing biomimetic approaches, artificial photosynthesis tries to construct systems doing the same type of processes. Ideally, a triad assembly could oxidize water with one catalyst, reduce protons with another and have a photosensitizer molecule to power the whole system.One of the simplest designs is where the photosensitizer is linked in tandem between a water oxidation catalyst and a hydrogen evolving catalyst:The photosensitizer transfers electrons to the hydrogen catalyst when hit by light, becoming oxidized in the process.This drives the water splitting catalyst to donate electrons to the photosensitizer. In a triad assembly, such a catalyst is often referred to as a donor.The oxidized donor is able to perform water oxidation.
43 PHOTOELECTROCHEMICAL CELLS The state of the triad with one catalyst oxidized on one end and the second one reduced on the other end of the triad is referred to as a charge separation, and is a driving force for further electron transfer, and consequently catalysis, to occur. The different components may be assembled in diverse ways, such as supramolecular complexes, compartmentalized cells, or linearly, covalently linked molecules.Research into finding catalysts that can convert water, carbon dioxide, and sunlight to carbohydrates or hydrogen is a current, active field. By studying the natural oxygen-evolving complex, researchers have developed catalysts such as the "blue dimer" to mimic its function.Photoelectrochemical cells that reduce carbon dioxide into carbon monoxide (CO), formic acid (HCOOH) and methanol (CH3OH) are under development. However, these catalysts are still very inefficient.In this process, hydrogen is produced from water using sunlight and specialized semiconductors called photoelectrochemical materials. In the photoelectrochemical (PEC) system, the semiconductor uses light energy to directly dissociate water molecules into hydrogen and oxygen. Different semiconductor materials work at particular wavelengths of light and energies.Sumber: diunduh 8/3/2012
44 HYDROGEN CATALYSTSHydrogen is the simplest solar fuel to synthesize, since it involves only the transference of two electrons to two protons. It must however be done stepwise, with formation of an intermediate hydride anion:2 e− + 2 H+ ↔ H+ + H− ↔ H2The proton-to-hydrogen converting catalysts present in nature are hydrogenases. These are enzymes that can either reduce protons to molecular hydrogen or oxidize hydrogen to protons and electrons. Spectroscopic and crystallographic studies spanning several decades have resulted in a good understanding of both the structure and mechanism of hydrogenase catalysis.Using this information, several molecules mimicking the structure of the active site of both nickel-iron and iron-iron hydrogenases have been synthesized.Other catalysts are not structural mimics of hydrogenase but rather functional ones.Synthesized catalysts include structural H-cluster models, a dirhodium photocatalyst, and cobalt catalysts.
45 WATER-OXIDIZING CATALYSTS Water oxidation is a more complex chemical reaction than proton reduction. In nature, the oxygen-evolving complex performs this reaction by accumulating reducing equivalents (electrons) in a manganese-calcium cluster within photosystem II (PS II), then delivering them to water molecules, with the resulting production of molecular oxygen and protons:2 H2O → O2 + 4 H+Without a catalyst (natural or artificial), this reaction is very endothermic, requiring high temperatures (at least 2500 K)(Bockris, J.O'M.; Dandapani, B.; Cocke, D.; Ghoroghchian, J. (1985). "On the splitting of water". International Journal of Hydrogen Energy 10 (3): 179–201).Sumber: diunduh 8/3/2012
46 WATER-OXIDIZING CATALYSTS The exact structure of the oxygen-evolving complex has been hard to determine experimentally.As of 2011, the most detailed model was from a 1.9Å resolution crystal structure of photosystem II(Yasufumi, Umena; Kawakami, Keisuke; Shen, Jian-Ren; Kamiya, Nobuo (5 May 2011). "Crystal structure of oxygen-evolving photosystem II at a resolution of 1.9 Å". Nature 473 (7345): 55–60).The complex is a cluster containing four manganese and one calcium ions, but the exact location and mechanism of water oxidation within the cluster is unknown. Nevertheless, bio-inspired manganese and manganese-calcium complexes have been synthesized, such as [Mn4O4] cubanes, some with catalytic activity(Dismukes, G. Charles; Brimblecombe, Robin; Felton, Greg A. N.; Pryadun, Ruslan S.; Sheats, John E.; Spiccia, Leone; Swiegers, Gerhard F. (2009). "Development of Bioinspired 4O4−Cubane Water Oxidation Catalysts: Lessons from Photosynthesis". Accounts of Chemical Research 42 (12): 1935–1943. )
47 WATER-OXIDIZING CATALYSTS Some ruthenium complexes, such as the dinuclear µ-oxo-bridged "blue dimer" (the first of its kind to be synthesized), are capable of light-driven water oxidation, thanks to being able to form high valence states. In this case, the ruthenium complex acts as both photosensitizer and catalyst.Many metal oxides have been found to have water oxidation catalytic activity, including ruthenium(IV) oxide (RuO2), iridium(IV) oxide (IrO2), cobalt oxides (including nickel-doped Co3O4), manganese(III) oxide (Mn2O3), and a mix of Mn2O3 with CaMn2O4. Oxides are easier to obtain than molecular catalysts, especially those from relatively abundant transition metals (cobalt and manganese), but suffer from low turnover frequency and slow electron transfer properties, and their mechanism of action is hard to decipher and, therefore, to adjust.(Carraro, Mauro; Sartorel, Andrea; Toma, Francesca; Puntoriero, Fausto; Scandola, Franco; Campagna, Sebastiano; Prato, Maurizio; Bonchio, Marcella (2011). "Artificial Photosynthesis Challenges: Water Oxidation at Nanostructured Interfaces". Topics in Current Chemistry 303: 121–150).Sumber: … diunduh 8/3/2012
48 PHOTOSENSITIZERSNature uses pigments, mainly chlorophylls, to absorb a broad part of the visible spectrum. Artificial systems can use either one type of pigment with a broad absorption range or combine several pigments for the same purpose.Ruthenium polypyridine complexes, in particular tris(bipyridine)ruthenium(II) and its derivatives, have been extensively used in hydrogen photoproduction due to their efficient visible light absorption and long-lived consequent metal-to-ligand charge transfer excited state, which makes the complexes strong reducing agents(Andreiadis, Eugen S.; Chavarot-Kerlidou, Murielle; Fontecave, Marc; Artero, Vincent (September/October 2011). "Artificial Photosynthesis: From Molecular Catalysts for Light-driven Water Splitting to Photoelectrochemical Cells". Photochemistry and Photobiology 87 (5): 946–964)A chlorophyll benefit for the body comes in liquid form. This herbal medicine can provide and prevent many aliments. A chlorophyll benefit can prevent cancer. It can also help with liver issues, prevent the body from becoming moldy and can abolish body order forever. This medication is an excellent treatment for the health and well-being of every individual. Chlorophyll is the life of all plants, it is what makes them grow and survive.Sumber: ... diunduh 8/3/2012
49 PHOTOSENSITIZERSOther noble metal-containing complexes used include ones with platinum, rhodiu and iridium.Metal-free organic complexes have also been successfully employed as photosensitizers. Examples include eosin Y and rose bengal.Pyrrole rings such as porphyrins have also been used in coating nanomaterials or semiconductors for both homogeneous and heterogeneous catalysis(Carraro, Mauro; Sartorel, Andrea; Toma, Francesca; Puntoriero, Fausto; Scandola, Franco; Campagna, Sebastiano; Prato, Maurizio; Bonchio, Marcella (2011). "Artificial Photosynthesis Challenges: Water Oxidation at Nanostructured Interfaces". Topics in Current Chemistry 303: 121–150).Singlet oxygen reacts readily with many biological substrates including certain amino acids in proteins, mainly tryptophan, tyrosine, histidine, cysteine and methionine. It also reacts with the guanine bases of DNA and RNA, as well as a variety of unsaturated lipids, including cholesterol and unsaturated fatty acids. It does not, however, affect carbohydrates appreciably.Sumber: ... diunduh 8/3/2012
50 CARBON DIOXIDE REDUCTION CATALYSTS In nature, carbon fixation is done on green plants using the enzyme RuBisCO as a part of the Calvin cycle. RuBisCO is a rather slow catalyst compared to the vast majority of other enzymes, incorporating only a few molecules of carbon dioxide into ribulose-1,5-bisphosphate per minute, but does so at atmospheric pressure and in mild, biological conditions (Ellis J.R. (2010). "Tackling unintelligent design". Nature 463 (7278): 164–165. Bibcode 2010Natur E)The resulting product is further reduced and eventually used in the synthesis of glucose, which in turn is a precursor to more complex carbohydrates, such as cellulose and starch.The process consumes energy in the form of ATP and NADPH.
51 CARBON DIOXIDE REDUCTION CATALYSTS Artificial CO2 reduction for fuel production aims mostly at producing reduced carbon compounds from atmospheric CO2. Some transition metal polyphosphine complexes have been developed for this end; however, they usually require previous concentration of CO2 before use, and carriers (molecules that would fixate CO2) that are both stable in aerobic conditions and able to concentrate CO2 at atmospheric concentrations haven't been yet developed(Dubois, M. Rakowski; Dubois, Daniel L. (2009). Accounts of Chemical Research 42 (12): 1974–1982).The simplest product from CO2 reduction is carbon monoxide (CO), but for fuel development, further reduction is needed, and a key step also needing further development is the transfer of hydride anions to CO.
52 THE CALVIN CYCLEIn the case of the Calvin Cycle, the input molecules are carbon dioxide, ATP, and NADPH. The output molecules are sugar, ADP, NADP+, and inorganic phosphate (Pi).The recycled molecule is ribulose bisphosphate (RuBP). Look at this figure and take a moment to locate these molecules.sumber;: https://wikispaces.psu.edu/display/110Master/Energy+V+-+Photosynthesis+%28Calvin+Cycle%29 ….. Diunduh 8/3/2012
53 SUSTAINABLE ENERGYSustainable energy is the provision of energy that meets the needs of the present without compromising the ability of future generations to meet their needs. Sustainable energy sources include all renewable energy sources, such as hydroelectricity, ocean thermal, orbital solar, terrestrial solar, wind energy, wave power, geothermal energy, and tidal power.It usually also includes technologies designed to improve energy efficiency.
54 EFISIENSI ENERGIEnergy efficiency and renewable energy are said to be the twin pillars of sustainable energy. Some ways in which sustainable energy has been defined are:"Effectively, the provision of energy such that it meets the needs of the present without compromising the ability of future generations to meet their own needs. ...Sustainable Energy has two key components: renewable energy and energy efficiency." – Renewable Energy and Efficiency Partnership (British)"Dynamic harmony between equitable availability of energy-intensive goods and services to all people and the preservation of the earth for future generations." And, "the solution will lie in finding sustainable energy sources and more efficient means of converting and utilizing energy." – Sustainable energy by J. W. Tester, et al., from MIT Press."Any energy generation, efficiency & conservation source where: Resources are available to enable massive scaling to become a significant portion of energy generation, long term, preferably 100 years.." – Invest, a green technology non-profit organization."Energy which is replenishable within a human lifetime and causes no long-term damage to the environment." – Jamaica Sustainable Development Network"The Twin Pillars of Sustainable Energy: Synergies between Energy Efficiency and Renewable Energy Technology and Policy". Aceee.org. Archived from the original on May 5, enewable Energy and Efficiency Partnership (August 2004). "Glossary of terms in sustainable energy regulation" (PDF). "The Sustainable Energy Community :: invVest | invVEST Definition of Sustainable Energy". invVest.Jamaica Sustainable Development Network. "Glossary of terms". Archived from the original on
55 GREEN ENERGYThis sets sustainable energy apart from other renewable energy terminology such as alternative energy and green energy, by focusing on the ability of an energy source to continue providing energy. Sustainable energy can produce some pollution of the environment, as long as it is not sufficient to prohibit heavy use of the source for an indefinite amount of time. Sustainable energy is also distinct from Low-carbon energy, which is sustainable only in the sense that it does not add to the CO2 in the atmosphere.Green Energy is energy that can be extracted, generated, and/or consumed without any significant negative impact to the environment. The planet has a natural capability to recover which means pollution that does not go beyond that capability can still be termed green.Green power is a subset of renewable energy and represents those renewable energy resources and technologies that provide the highest environmental benefit. The U.S. Environmental Protection Agency defines green power as electricity produced from solar, wind, geothermal, biogas, biomass, and low-impact small hydroelectric sources. Customers often buy green power for avoided environmental impacts and its greenhouse gas reduction benefits.Green Power Defined | Green Power Partnership | US EPA". Epa.gov
56 GREEN ENERGYGreen energy includes natural energetic processes that can be harnessed with little pollution. Anaerobic digestion, geothermal power, wind power, small-scale hydropower, solar energy, biomass power, tidal power, wave power, and some forms of nuclear power (which is able to "burn" nuclear waste through a process known as nuclear transmutation, and therefore belong in the "Green Energy" category). Some definitions may also include power derived from the incineration of waste.Some people, including George Monbiot and James Lovelock have specifically classified nuclear power as green energy. Others, including Greenpeace disagree, claiming that the problems associated with radioactive waste and the risk of nuclear accidents (such as the Chernobyl disaster) pose an unacceptable risk to the environment and to humanity. However, newer nuclear reactor designs are capable of utilizing what is now deemed "nuclear waste" until it is no longer (or dramatically less) dangerous, and have design features that greatly minimize the possibility of a nuclear accident.No power source is entirely impact-free. All energy sources require energy and give rise to some degree of pollution from manufacture of the technology.The Guardian (London).Lovelock, James (2006). The Revenge of Gaia. Reprinted Penguin, ISBN"End the nuclear age | Greenpeace International". Greenpeace.org. Retrieved
57 GREEN ENERGYNo power source is entirely impact-free. All energy sources require energy and give rise to some degree of pollution from manufacture of the technology.In several countries with common carrier arrangements, electricity retailing arrangements make it possible for consumers to purchase green electricity (renewable electricity) from either their utility or a green power provider.When energy is purchased from the electricity network, the power reaching the consumer will not necessarily be generated from green energy sources. The local utility company, electric company, or state power pool buys their electricity from electricity producers who may be generating from fossil fuel, nuclear or renewable energy sources.In many countries green energy currently provides a very small amount of electricity, generally contributing less than 2 to 5% to the overall pool. In some U.S. states, local governments have formed regional power purchasing pools using Community Choice Aggregation and Solar Bonds to achieve a 51% renewable mix or higher, such as in the City of San Francisco.San Francisco Community Choice Program Design, Draft Implementation Plan and H Bond Action Plan, Ordinance , 2007.
58 GREEN ENERGY = ENERGI HIJAU By participating in a green energy program a consumer may be having an effect on the energy sources used and ultimately might be helping to promote and expand the use of green energy. They are also making a statement to policy makers that they are willing to pay a price premium to support renewable energy.Green energy consumers either obligate the utility companies to increase the amount of green energy that they purchase from the pool (so decreasing the amount of non-green energy they purchase), or directly fund the green energy through a green power provider.If insufficient green energy sources are available, the utility must develop new ones or contract with a third party energy supplier to provide green energy, causing more to be built. However, there is no way the consumer can check whether or not the electricity bought is "green" or otherwise.
59 GREEN ENERGYIn some countries such as the Netherlands, electricity companies guarantee to buy an equal amount of 'green power' as is being used by their green power customers.In the United States, one of the main problems with purchasing green energy through the electrical grid is the current centralized infrastructure that supplies the consumer’s electricity. This infrastructure has led to increasingly frequent brown outs and black outs, high CO2 emissions, higher energy costs, and power quality issues.Renewable resources, due to the amount of space they require, are often located in remote areas where there is a lower energy demand. The current infrastructure would make transporting this energy to high demand areas, such as urban centers, highly inefficient and in some cases impossible. In addition, despite the amount of renewable energy produced or the economic viability of such technologies only about 20 percent will be able to be incorporated into the grid. To have a more sustainable energy profile, the United States must move towards implementing changes to the electrical grid that will accommodate a mixed-fuel economy.U.S. Department of Energy Office of Electricity Delivery and Energy Reliability."Energy Distribution"U.S. Department of Energy Office of Electricity Delivery and Energy Reliability.[Whittington, H.W. "Electricity generation: Options for reduction in carbon emissions". Philosophical transactions in mathematics, physical, and engineering sciences. Vol. 360, No (Aug. 15, 2002) Published by: The Royal Society]
60 GREEN ENERGYSeveral initiatives are being proposed to mitigate these distribution problems. First and foremost, the most effective way to reduce USA’s CO2 emissions and slow global warming is through conservation efforts. Opponents of the current US electrical grid have also advocated for decentralizing the grid.This system would increase efficiency by reducing the amount of energy lost in transmission. It would also be economically viable as it would reduce the amount of power lines that will need to be constructed in the future to keep up with demand.Merging heat and power in this system would create added benefits and help to increase its efficiency by up to 80-90%. This is a significant increase from the current fossil fuel plants which only have an efficiency of 34%.. Romm, Joseph; Levine, Mark; Brown, Marilyn; Peterson, Eric. “A road map for U.S. carbon reductions”. Science, Vol. 279, No (Jan. 30, 1998). Washington
61 GREEN ENERGYA more recent concept for improving our electrical grid is to beam microwaves from Earth-orbiting satellites or the moon to directly when and where there is demand. The power would be generated from solar energy captured on the lunar surface In this system, the receivers would be “broad, translucent tent-like structures that would receive microwaves and convert them to electricity”. NASA said in 2000 that the technology was worth pursuing but it is still too soon to say if the technology will be cost-effective.The World Wide Fund for Nature and several green electricity labelling organizations have created the Eugene Green Energy Standard under which the national green electricity certification schemes can be accredited to ensure that the purchase of green energy leads to the provision of additional new green energy resources.[Britt, Robert Roy. “Could Space-Based Power Plants Prevent Blackouts?”. Science. (August 15, 2003)] ^ Eugene Green Energy Standard, Eugene Network. Retrieved
62 ENERGI HIJAURenewable energy, after its generation, needs to be stored in a medium for use with autonomous devices as well as vehicles. Also, to provide household electricity in remote areas (that is areas which are not connected to the mains electricity grid), energy storage is required for use with renewable energy. Energy generation and consumption systems used in the latter case are usually stand-alone power systems.Some examples are:energy carriers as hydrogen, liquid nitrogen, compressed air, oxyhydrogen, batteries, to power vehicles.flywheel energy storage, pumped-storage hydroelectricity is more usable in stationary applications (e.g. to power homes and offices. In household power systems, conversion of energy can also be done to reduce smell. For example organic matter such as cow dung and spoilable organic matter can be converted to biochar. To eliminate emissions, carbon capture and storage is then used.
63 RENEWABLE ENERGYUsually however, renewable energy is derived from the mains electricity grid. This means that energy storage is mostly not used, as the mains electricity grid is organised to produce the exact amount of energy being consumed at that particular moment. Energy production on the mains electricity grid is always set up as a combination of (large-scale) renewable energy plants, as well as other power plants as fossil-fuel power plants and nuclear power.This combination however, which is essential for this type of energy supply (as e.g. wind turbines, solar power plants etc.) can only produce when the wind blows and the sun shines. This is also one of the main drawbacks of the system as fossil fuel powerplants are polluting and are a main cause of global warming (nuclear power being an exception). Although fossil fuel power plants too can made emissionless (through carbon capture and storage), as well as renewable (if the plants are converted to e.g. biomass) the best solution is still to phase out the latter power plants over time. Nuclear power plants too can be more or less eliminated from their problem of nuclear waste through the use of nuclear reprocessing and newer plants as fast breeder and nuclear fusion plants.
64 RENEWABLE ENERGY POWER PLANTS Renewable energy power plants do provide a steady flow of energy. For example hydropower plants, ocean thermal plants, osmotic power plants all provide power at a regulated pace, and are thus available power sources at any given moment (even at night, windstill moments etc.). At present however, the number of steady-flow renewable energy plants alone is still too small to meet energy demands at the times of the day when the irregular producing renewable energy plants cannot produce power.Besides the greening of fossil fuel and nuclear power plants, another option is the distribution and immediate use of power from solely renewable sources. In this set-up energy storage is again not necessary.For example, TREC has proposed to distribute solar power from the Sahara to Europe. Europe can distribute wind and ocean power to the Sahara and other countries. In this way, power is produced at any given time as at any point of the planet as the sun or the wind is up or ocean waves and currents are stirring. This option however is probably not possible in the short-term, as fossil fuel and nuclear power are still the main sources of energy on the mains electricity net and replacing them will not be possible overnight.
65 ENERGY STORAGESeveral large-scale energy storage suggestions for the grid have been done. This improves efficiency and decreases energy losses but a conversion to a energy storing mains electricity grid is a very costly solution. Some costs could potentially be reduced by making use of energy storage equipment the consumer buys and not the state. An example is car batteries in personal vehicles that would double as an energy buffer for the electricity grid. However besides the cost, setting-up such a system would still be a very complicated and difficult procedure.Energy storage apparatus' as car batteries are also built with materials that pose a threat to the environment (e.g. sulphuric acid).The combined production of batteries for such a large part of the population would thus still not quite environmental.Besides car batteries however, other large-scale energy storage suggestions for the grid have been done which make use of less polluting energy carriers (e.g. compressed air tanks and flywheel energy storage).
66 ENERGY CONSERVATIONEnergy conservation refers to efforts made to reduce energy consumption. Energy conservation can be achieved through increased efficient energy use, in conjunction with decreased energy consumption and/or reduced consumption from conventional energy sources.Energy conservation can result in increased financial capital, environmental quality, national security, personal security, and human comfort.Individuals and organizations that are direct consumers of energy choose to conserve energy to reduce energy costs and promote economic security. Industrial and commercial users can increase energy use efficiency to maximize profit.
67 KEBIJAKAN ENERGIEnergy policy is the manner in which a given entity (often governmental) has decided to address issues of energy development including energy production, distribution and consumption.The attributes of energy policy may include legislation, international treaties, incentives to investment, guidelines for energy conservation, taxation and other public policy techniques.
68 It usually also includes technologies that improve energy efficiency. SUSTAINABLE ENERGYSustainable energy is the provision of energy that meets the needs of the present without compromising the ability of future generations to meet their needs.Sustainable energy sources are most often regarded as including all renewable energy sources, such as hydroelectricity, solar energy, wind energy, wave power, geothermal energy, bioenergy, and tidal power.It usually also includes technologies that improve energy efficiency.
69 PENGGUNAAN BIOFUELBiofuel is defined as solid, liquid or gaseous fuel obtained from relatively recently lifeless or living biological material and is different from fossil fuels, which are derived from long dead biological material.Various plants and plant-derived materials are used for biofuel manufacturing.Bio fuels are a renewable energy and can be sustainable (carbon neutral) in terms of greenhouse gas emissions since they are in the carbon cycle for the short term.
70 KAYU BAKARUnsustainable firewood harvesting can lead to loss of biodiversity and erosion due to loss of forest cover. An example of this is a 40 year study done by the University of Leeds of African forests, which account for a third of the world's total tropical forest which demonstrates that Africa is a significant carbon sink.A climate change expert, Lee White states that "To get an idea of the value of the sink, the removal of nearly 5 billion tonnes of carbon dioxide from the atmosphere by intact tropical forests is at issue.According to the U.N. the continent is losing forest twice as fast as the rest of the world. "Once upon a time, Africa boasted seven million square kilometers of forest but a third of that has been lost, most of it to charcoal.”Rowan, Anthea ( ). "Africa's burning charcoal problem". BBC NEWS Africa. Retrieved
71 DAMPAK LINGKUNGAN Petroleum The environmental impact of petroleum is often negative because it is toxic to almost all forms of life. The possibility of climate change exists.Petroleum, commonly referred to as oil, is closely linked to virtually all aspects of present society, especially for transportation and heating for both homes and for commercial activities.
72 GAS ALAMNatural gas is often described as the cleanest fossil fuel, producing less carbon dioxide per joule delivered than either coal or oil., and far fewer pollutants than other fossil fuels. However, in absolute terms it does contribute substantially to global carbon emissions, and this contribution is projected to grow.According to the IPCC Fourth Assessment Report, in 2004 natural gas produced about 5,300 Mt/yr of CO2 emissions, while coal and oil produced 10,600 and 10,200 respectively; but by 2030, according to an updated version of the SRES B2 emissions scenario, natural gas would be the source of 11,000 Mt/yr, with coal and oil now 8,400 and 17,200 respectively. (Total global emissions for 2004 were estimated at over 27,200 Mt.)In addition, natural gas itself is a greenhouse gas far more potent than carbon dioxide when released into the atmosphere but is released in smaller amounts.
73 PEMBANGKIT LISTRIKThe environmental impact of electricity generation is significant because modern society uses large amounts of electrical power.This power is normally generated at power plants that convert some other kind of energy into electrical power. Each such system has advantages and disadvantages, but many of them pose environmental concerns.
74 AKIBAT BENDUNGAN-WADUK DAMPAK LINGKUNGANAKIBAT BENDUNGAN-WADUKThe environmental impact of reservoirs is coming under ever increasing scrutiny as the world demand for water and energy increases and the number and size of reservoirs increases.Dams and the reservoirs can be used to supply drinking water, generate hydroelectric power, increasing the water supply for irrigation, provide recreational opportunities and to improve certain aspects of the environment. However, adverse environmental and sociological impacts have also been identified during and after many reservoir constructions. Whether reservoir projects are ultimately beneficial or detrimental—to both the environment and surrounding human populations— has been debated since the 1960s and probably long before that. In 1960 the construction of Llyn Celyn and the flooding of Capel Celyn provoked political uproar which continues to this day. More recently, the construction of Three Gorges Dam and other similar projects throughout Asia, Africa and Latin America have generated considerable environmental and political debate.
75 Why Australia needs wind power ENERGI ANGINCompared to the environmental effects of traditional energy sources, the environmental effects of wind power are relatively minor. Wind power consumes no fuel, and emits no air pollution, unlike fossil fuel power sources. The energy consumed to manufacture and transport the materials used to build a wind power plant is equal to the new energy produced by the plant within a few months.While a wind farm may cover a large area of land, many land uses such as agriculture are compatible, with only small areas of turbine foundations and infrastructure made unavailable for use.Why Australia needs wind power
76 GREEN ENERGY TECHNOLOGY What is Renewable Energy?
77 ENERGI ALTERNATIFThe term alternative energy is commonly used. It does in our global society simply refer to the use of other sources of energy other than primary energy sources like fossil fuel. When we talk about fossil fuels coal, natural gas and oil are the main elements. They are used to generate electricity, heating and to power our massive transport sector.
78 APA SAJA MANFAAT ENERGI-HIJAU Green energy is becoming progressively more popular day by day as it provides myriads of benefits. It is a sustainable, reliable and comprehensive source of energy that requires little or no maintenance and is beneficial in the long run.Using green energy is an extremely reliable way to save your monthly expenditures on electricity bills. It is a renewable form of energy that utilizes sunlight to produce electricity.
79 ENERGI MATAHARISolar energy is beneficial for our health as it neither pollutes the environment nor does it release any harmful substances into the air. In this article, I will discuss some of the most effective benefits of this renewable energy so you can easily understand the importance of this reliable alternative source.
80 BIOMASABiomass is also a very popular alternative source of energy. The energy is derived from burning plants, and it is one of man’s first sources of energy. Very recently, wood was still the primary sources for heat, and it can still be seen as being the main one in developing countries. However, in the developed countries wood is mostly used for aesthetic purposes. Nevertheless, there are still roughly around 2 billion people in developing nations that use wood for “heating and cooking”.Moreover, biomass does also have some other derivates such as “bio-diesel and ethanol”. These are direct substitutes for oil in the automobile industry.
81 Biomass Energy from bio matter = Renewable Energy is biological material use to generate renewable energy. What is used as biomass: plants, grass, wood, waste With Biomass we can generate electricity or produce heat. Dead trees, branches and tree stumps, yard clippings and wood chips may be used as bio-fuel.SUMBER: … diunduh 10/3/2012
82 Sunlight is necessary to produce Biomass Sunlight is necessary to produce Biomass! Sunshine gives us warmth, let the plants grow and moves the air.Sumber: diunduh 10/3/2012
83 BIOMASS ENERGY SOURCES Sumber: ….. Diunduh 10/3/2012
84 PRODUKSI ENERGI BIOMASA Biomass energy production, at its core, is the use of: photosynthesis to capture solar energy, organic carbon compounds to store the energy, chemical and/or biological processes to extract and convert the stored biomass energy into fossil equivalent fuels called biofuels, and finally, combustion of the biofuels. Biofuels are fuels that are derived from the biological material of living or recently living organisms called 'biomass'. In the modern era most biofuels are derived directly from the biomass of photosynthetic organisms, such as ethanol from the stalks of the sugarcane plant, whereas in centuries past biofuels were sometimes derived from photosynthesis indirectly, such as from animal biomass, e.g. oils from the blubber of whales. Some biomass can be used directly as biofuel without further processing, such as the dry cellulose from trees used in wood stoves. However, most biofuels with higher energy densities such as ethanol, require processing of the raw biomass into biofuel. In cases where the biomass has to be processed, it is called 'feedstock'. For ethanol, common feedstocks are sugarcane, corn, and sugar beet.For diesels, common feedstocks are rapeseed (aka canola), soybeans, and palm nuts. For bio-oil the feedstock can be a wide array of hydrocarbon containing materials.Sumber: …. Diunduh 10/3/2012
85 Biomass energy production begins with the use of photosynthesis to capture solar energy. Nature evolved a system to harness the energy in solar photons hundreds of millions of years ago, which we call photosynthesis. Photons strike antenna chlorophyll molecules in plants, which excites electrons in the photo-reaction centers attached to the antennas to higher energy levels. The electrons are then separated by the chlorophyll photo-reaction center from the electron holes they leave behind and the two are able to react separately with different molecules on opposite sides of the photo-reaction center, with the electron reducing CO2 and protons (H+) to carbohydrates (CH2O) and with the electron hole oxidizing H2O to oxygen (O2), protons (H+), and electrons (e-).Sumber: …. Diunduh 10/3/2012
86 COMBUSTION OF THE BIOFUELS The energy stored in the biofuels must be extracted somehow. Extraction of energy from the biofuels typically is done via combustion. Combustion is the reaction of a fuel with oxygen which results in the release of energy.The bonds in O2 and the bonds in the fuel are broken to form the component atoms in a transition state, this requires energy input because free atoms are less stable than bonded atoms (which can be initially provided by a spark and later provided by the second stage of the reaction).In the transition state the atoms recombine to form the product molecules, this releases energy because bonded atoms are more stable than free atoms.As long as the formation of the product releases more energy than the input energy to break the reactant, the reaction will propagate and there will be energy release in the form of heat.Sumber: …. Diunduh 10/3/2012
87 ENVIRONMENT AND RENEWABLE ENERGY Biomass Conversion into Energy Ancient way of converting biomass into energy is just to burn it for producing heat, as humans practiced it for thousands of years. Still this is the most common way for conversion of biomass into energy in United States and elsewhere also.The heat generated from biomass can be used for heating, cooking, and industrial processes, or for producing electricity.Sumber: …. Diunduh 10/3/2012
88 WOODY BIOMASS RESOURCES Biomass may be used for energy production at different scales, including large-scale power generation, CHP, or small-scale thermal heating projects at governmental, educational or other institutions. Biomass comes from both human and natural activities and incorporates by-products from the timber industry, agricultural crops, forestry residues, household wastes, and wood. The resources range from corn kernels to corn stalks, from soybean and canola oils to animal fats, from prairie grasses to hardwoods, and even include algae. The largest source of energy from wood is pulping liquor or black liquor, a waste product from the pulp and paper industry.Woody biomass is the most important renewable energy source if proper management of vegetation is ensured. The main benefits of woody biomass are as follows:Uniform distribution over the world’s surface, in contrast to finite sources of energy.Less capital-intensive conversion technologies employed for exploiting the energy potential.Attractive opportunity for local, regional and national energy self-sufficiency.Techno-economically viable alternative to fast-depleting fossil fuel reserves.Reduction in GHGs emissions.Provide opportunities to local farmers, entrepreneurs and rural population in making use of its sustainable development potential.Sumber: ….. Diunduh 10/3/2012
89 BIOMASS RESOURCESBiomass processing systems constitute a significant portion of the capital investment and operating costs of a biomass conversion facility depending on the type of biomass to be processed as well as the feedstock preparation requirements. Its main constituents are systems for biomass storage, handling, conveying, size reduction, cleaning, drying, and feeding. Harvesting biomass crops, collecting biomass residues, and storing and transporting biomass resources are critical elements in the biomass resource supply chain.All processing of biomass yields by-products and waste streams collectively called residues, which have significant energy potential. A wide range of biomass resources are available for transformation into energy in natural forests, rural areas and urban centres. Some of the sources have been discussed in the following paragraphs:Sumber: … diunduh 10/3/2012
90 What is biomass electricity? Why is biomass electricity important? Biomass electricity is drawn from combusting or decomposing organic matter. There are about 132 waste-to-energy plants in California, with a total capacity of almost 1,000 megawatts. These plants power our homes and businesses with electricity from waste matter that would have been released into the atmosphere, added fuel to forest fires, and burdened our landfills.Why is biomass electricity important?Using biomass to produce electricity reduces our reliance on fossil fuels, the nation's primary energy sources for electricity, and the largest contributors to air pollution and greenhouse gases. We will eventually run out of fossil fuels. Biomass electricity offers alternatives with many benefits:Our supply of biomass is renewable, meaning it will not run out.Electricity produced by biomass reduces the threat of global climate change.Using biomass waste eliminates the need to place it in landfills.Clearing biomass from wooded areas helps prevent forest fires.Using by-product methane gases to produce electricity eliminates odor and reduces air pollution in surrounding areas.Sumber: … diunduh 10/3/2012
92 Biomass is the name given to any material which is recently derived from plants that use sunlight to grow, such as wood from forests, material left over from agricultural and forestry processes, and organic industrial, human and animal material. It is sometimes classified as ‘combustible renewables and waste’.The energy contained in biomass originally came from the sun. Through photosynthesis carbon dioxide in the air is transformed into other carbon containing molecules (e.g. sugars, starches and cellulose) in plants. The chemical energy that is stored in plants and animals (animals eat plants or other animals) or in their waste is called bio-energy.When biomass is burned it releases its energy, generally in the form of heat. The biomass carbon reacts with oxygen in the air to form carbon dioxide. If fully combusted the amount of carbon dioxide produced is equal to the amount which was absorbed from the air while the plant was growing.
93 The different pathways to transform biomass in energy
94 Sustainability: the capacity of smokeless biomass pyrolysis for energy production, global carbon capture and sequestration.James Weifu Lee, Bob Hawkins, Danny M. Day and Donald C. Reicosky Energy Environ. Sci., 2010, 3,SUMBER: Diunduh 9/3/2012
95 NEXT-GENERATION BIOFUELS One way to wean ourselves from oil is to come up with renewable sources of transportation fuel. That means a new generation of biofuels made from nonfood crops.Researchers are devising ways to turn lumber and crop wastes, garbage and inedible perennials like switchgrass into competitively priced fuels. But the most promising next-generation biofuel comes from algae.Algae grow by taking in CO2, solar energy and other nutrients. They produce an oil that can be extracted and added into existing refining plants to make diesel, gasoline substitutes and other products.Sumber: ….. Diunduh 9/3/2012
96 WHAT ARE MICROBIAL BIOFUELS? Microorganisms convert biomass into chemicals that can be used as transport biofuels. Production of fuel by microbes is not new - mankind has been fermenting and distilling alcohol for millennia; the only difference is that the alcohol is destined for use in combustion engines rather than human consumption. Microbial production of methane, ethanol and butanol have been around for many years, while biohydrogen and oil from algae remain for future development.Sumber: ….. Diunduh 9/3/2012
97 WHAT ARE MICROBIAL BIOFUELS? Methane is produced by anaerobic digestion of waste organic materials. Its use as a fuel is limited with most used in Combined Heat and Power (CHP) systems. Biohydrogen is used in hydrogen fuel cells to generate electricity. Current production is limited by the cost of reactors required for photochemical synthesis and the low yields from anaerobic fermentation. Oil from microalgae is a new technology. Over 40% of the mass of some microalgae is oil which can be extracted and used as biodiesel. The biggest challenge to oilgae is to reduce the cost of cultivation and improve the biology of oil production. Bioethanol is currently produced by yeast (Saccharomyces cerevisiae) fermentation of sugar and starch crops.Any move away from food crops is limited by the sugars that can be used by yeast. Glucose is the preferred substrate and conversion of other carbohydrates such as those in lignocellulose into ethanol requires genetic engineering of novel yeast and bacterial strains. Biobutanol is now recognised as a superior biofuel to ethanol. In addition to the beneficial fuel properties, the solventogenic clostridia used in the fermentation also have an inherent advantage. Clostridia can utilise a wide variety of carbohydrates, allowing all the carbohydrates, in addition to glucose, in biomass to be converted to fuel.Sumber: ….. Diunduh 9/3/2012
98 WHICH BIOMASS? FOR BIOFUELS One of the main costs in biofuel production, in terms of both economics and environment, is the biomass feedstock. The choice of feedstock is central to the controversy surrounding biofuels today, with current technologies associated with the use of food as fuel and large scale changes in land usage. For biofuels to have any meaningful impact on energy, biomass feedstocks must be widely available at low cost and without negative environmental impact. Lignocellulose - the non-food component of plants, fits this description. Future technologies are based on harnessing the energy locked within lignocellulose, converting the carbohydrate components to biofuel. Sumber: Diunduh 9/3/2012
99 LIGNOCELLULOSE BIOMASS INCLUDES Agricultural waste such as straw, corn stover and bagasse.Industrial waste such as sawdust and paper pulp.Woody biomass from forestry.Municipal solid waste including food and garden waste and paper products.Specific non-food energy crops such as switchgrass. Conversion to biofuel first requires hydrolysis of the biomass to yield a fermentable susbtrate. This step often involves a combination of physical, chemical and enzymatic treatments. Complete hydrolysis of the polysaccharide polymers yields glucose from cellulose and a complex mixture of sugars from hemicellulose including pentoses (xylose and arabinose) and hexoses (glucose, mannose, galactose and rhamnose). The second step is to ferment the hydrolysate to biofuel. In order for a lignocellulose process to be efficient, it is desirable for the microbes to utilise all of the carbohydrates. It is here that solventogenic clostridia have the advantage, enabling complete conversion of lignocellulosic sugars to butanol and co-products.Sumber: Diunduh 9/3/2012
100 WHAT ARE BIOFUELS?Biofuels are any liquid, solid or gaseous fuels produced from organic matter. The extensive range of organic materials used for biofuel production includes starch and sugary plants such as corn, wheat or sugar cane; oily plants such as rape seed, soya beans or jatropha; vegetable oils and animal fats; wood and straw; algae and organic waste and others.Biofuels are commonly referred to as first generation, mainly bioethanol and biodiesel, or second generation, which cover a variety of technologies currently in the pipeline.In the wake of environmental concerns and volatility of oil supply the development of alternative fuels is crucial to the future of the transport sector. This need has been widely recognized by policy makers and resulted in the introduction of European Biofuel Directive in 2003 and UK Road Transport Fuel Obligation in Both documents call for 5% biofuel blends with fossil fuels by Currently biofuels substitute around 2.6% of all transport fuels sold in the UK.Sumber: Diunduh 9/3/2012
101 FIRST GENERATION BIOFUELS The two most common 1st generation biofuels are bioethanol from starch or sugar crops and biodiesel from oil-rich plants. As these fuels are primarily derived from crops which may also be used as food for animals and humans, these type of fuels have been criticised for diverting food away from the human food chain to theengine.Biofuels’ impact on the environment and food prices and sustainability of production are often scrutinized in mass media. Research in the field suggests however, that whilst still depending on method of production, the overall green house gas emission savings are positive and in some cases zero carbon production is possible as carbon emitted during the burning of biofuels is compensated by the carbon absorbed by the plants as they grow.Impact on biodiversity may be negative, however, in many cases the cultivation of biofuels may enhance biodiversity, especially if underutilized agricultural land is used for production. Biofuels will only negatively impact food markets if they compete for land with the agricultural sector.Sumber: ….. Diunduh 9/3/2012
102 SECOND GENERATION BIOFUELS Second generation biofuels are broadly speaking the biofuel technologies still in the pipeline. It is these sustainable biofuels that will provide the source for the future. Some of the new technologies focus on increasing yields from plant-derived fuels; others look at the application of microbiological research to improve energy efficiency and range of renewable feedstocks for biofuel production. The Biofuel Research Centre focuses on 2nd Generation biofuels produced by microbial fermentation of non-food crops. These carbon-rich lignocellulosic materials are renewable and widely available. Sources include agricultural waste such as corn stover, straw and bagasse; industrial waste such as sawdust and paper pulp; woody biomass from forestry; municipal solid waste including household food and garden waste and paper products; and specific non-food energy crops such as switchgrass.Conversion of lignocellulosic biomass is attractive and even more so if biomass which is otherwise regarded as waste can be used as the substrate. In this case, the overall energy yield and carbon footprint will be improved compared to first generation biofuels as there is no need to cultivate and harvest the crops. How we best harness this energy stored within lignocelluloses may provide the solution for biofuels in the future.Sumber: ….. Diunduh 9/3/2012
103 CORN ETHANOLThe above graph shows the cycle of producing ethanol from corn. There are two big steps that require a lot of energy in the process, namely hydrolysis (where the starch molecules from plants break down) and then fermentation (where glucose is turned into ethanol by adding yeast). The latter though is exactly the same process we use to produce alcohol!Sumber: Diunduh 9/3/2012
104 CORN ETHANOLCorn ethanol will never work ultimately, because it requires a lot of fossil fuels energy at various stages in order to produce it. It is not a renewable source, and the maximum net energy gain is at best +30% compared to conventional gasoline. It's a good start, but not worth it.Sumber: ….. Diunduh 9/3/2012
105 CELLULOSIC ETHANOLWhat COULD potentially work is ethanol extracted from cellulose, which is the wall found in all plants (not just corn). This increases dramatically the potential crop sources one can use to get the energy.Sumber: ….. Diunduh 9/3/2012
106 CELLULOSIC ETHANOLThe graph above shows the potential energy that can be extracted from various sources, in terms of the energy required to produce it (so it's and output/input graph).While electricity and gas have values smaller than one (they have negative balance, i.e. they are not renewable), cellulosic ethanol has the greatest potential of all.Sumber: ….. Diunduh 9/3/2012
107 CELLULOSIC ETHANOLCellulosic ethanol is also the best option in terms of CO2 emissions, having very few when burned compared to fossil fuels and other biofuels.Sumber: ….. Diunduh 9/3/2012
108 CELLULOSECellulose comprises 45% of the material in plant walls, as the pictures above and below indicate.Sumber: ….. Diunduh 9/3/2012
109 CELLULOSEThe difficulty is to penetrate the plant wall and get the cellulose out. This is hard and expensive, because it is protected by lignin, which has a chemical composition similar to asphalt.Sumber: ….. Diunduh 9/3/2012
110 CELLULOSIC ETHANOLUntil now, it is very expensive and inefficient to extract ethanol from cellulose, despite its great potential.Sumber: ….. Diunduh 9/3/2012
111 CELLULOSIC ETHANOLPeople have been now searching various techniques to break it down more efficiently. When that happens, full-scale production of cellulosic ethanol will quickly spread.Sumber: ….. Diunduh 9/3/2012
112 SUGARCANE ETHANOLHere are some other biofuel options: Brazil has 40% of their cars running on sugarcane ethanol, and 85% of their cars are flex. This is because Brazil's climate allows the easier production of the more efficient (compared to corn) growth of sugarcane.Sumber: ….. Diunduh 9/3/2012
113 BIODIESEL FROM ALGAEBiodiesel from Algae the greatest potential for a biofuel, because it is the fastest growing plant on the planet, and captures huge quantities of CO2 for storage. However, it is still very expensive to harvest it and remains in the private sector.Sumber: ….. Diunduh 9/3/2012
114 THE LAW OF ALGAETHE LAW OF ALGAE is a guide to the business and legal issues in developing an algae biofuels facility. While algae or algal biomass can be processed to create a variety of biofuels, including ethanol or methanol, this book focuses on projects that will produce algae oil for conversion to biodiesel. A full-scale algae biofuels project developer will need to consider issues related to producing algae oil on a commercial scale and converting the algae oil into biodiesel.Sumber: ….. Diunduh 9/3/2012
115 ALGAE PRODUCTION ISSUES The commercial-scale production of algae requires careful consideration of many issues that can be broadly categorized into four main areas: selecting algae species that produce high oil levels and grow well in specified environments, algae growth methods, water sources and issues, and nutrient and growth inputs.Sumber: ….. Diunduh 9/3/2012
116 HARVESTING ALGAE AND EXTRACTING OIL While algae grows rapidly and produces large amounts of oil, harvesting the algae and extracting the oil present challenges to the commercial-scale development of algae. Many new technologies are being developed to address the harvesting and extraction challenges. The key will be whether the technologies are cost-efficient.Sumber: ….. Diunduh 9/3/2012