Presentation on theme: "Energy Resources and Fossil Fuels"— Presentation transcript:
1 Energy Resources and Fossil Fuels Environmental ScienceChapter 17 Section 1
2 Fossil FuelsThe remains of ancient organisms that changed into coal, oil, or natural gas.Fuels we use to run cars, ships, planes, and factories and to produce electricity.Natural resources.Two main problems:Supply is limited.Obtaining and using them causes environmental problems.
3 Fuels for Different Uses Fuels are used for five main purposes:CookingTransportationManufacturingHeating and cooling buildingsGenerating electricity to run machines and appliancesSustainability depends on the fuel’s energy content, cost, availability, and safety, and the byproducts of the fuel’s use.
4 Fuels for Different Uses Examples:CoalReadily available and inexpensiveUsed to heat homesAirplane fuelMore energy per mass than coalExpensiveWoodLow energy per mass comparativelyGenerally inexpensive
5 Electricity – Power on Demand Energy in fuels is often converted into electrical energy in order to power machines.Can be transported quickly across great distances.Generated in power plants.Disadvantages:Difficult to store.Other energy sources have to be used to generate it.
6 Electricity – Power on Demand How is Electricity Generated?Electric generator – machine that converts mechanical energy into electrical energy.Turbine – a wheel that changes the force of a moving gas or liquid into energy that can do work.Most power plants boil water to produce steam that turns the turbine.Turbine spins a generator to produce electricity.
8 Energy Use World Patterns People in developed societies use much more energy that people in developing countries.Energy use in some developing countries is growing rapidly.
9 Energy Use Energy Use in the United States The United States uses more energy per person than any other country in the world except for Canada and the United Arab Emirates.More than 25% is used to transport goods and people. Other countries have better mass transportation systems.Fuel is lower cost in the U.S. than other places, which leads to greater usage.
10 How Fossil-Fuel Deposits Form Coal FormationCoal forms from the remains of plants that lived in swamps hundreds of millions of years ago.Layers of sediment added as the sea level rose and fell and compressed the remains, causing coal to form.
11 How Fossil-Fuel Deposits Form Oil and Natural Gas FormationResult from the decay of tiny marine organisms that accumulated on the bottom of the ocean millions of years ago.Buried by sediments, then heated until they became complex energy-rich carbon-based molecules.Over time, molecules migrated into the porous rocks that now contain them.Much is found in Alaska, Texas, California, and the Gulf of Mexico.
13 Coal Coal Mining and the Environment Environmental effects of mining coal vary.Underground mines can have a minimal effect on the surface.Sometimes, it is necessary to disturb the surface of the land to reach the deposit.Toxic chemicals can leach into nearby streams.
14 CoalAir PollutionBituminous coal (high-grade) produces more heat and less pollution than lignite (low-grade).Sulfur is a major source of coal pollution.Results in acid rain.
15 Petroleum Petroleum – oil that is pumped from the ground – crude oil. Petroleum product – anything that is made from crude oil.FuelsChemicalsPlastics
16 Petroleum Locating Oil Deposits Oil is found in and around major geologic features, such as folds, faults, and salt domes.Impermeable layers of rock prevent the oil from escaping.Most of the world’s oil reserves are in the Middle East.Large deposits also exist in the U.S., Venezuela, the North Sea, Siberia, and Nigeria.Oil is removed from a well and then transported to a refinery to be converted into fuels and other petroleum products.
17 Petroleum The Environmental Effects of Using Oil When petroleum fuels are burned, they release pollutants.Emissions regulations and technology have helped to reduce air pollutants.Oil spills are dramatic, but cars leaking oil causes more pollution every day.
18 Petroleum Natural Gas About 20% of the world’s nonrenewable energy. Many oil wells recover natural gas.Fewer pollutants than other fuels.
19 Fossil Fuels and the Future Predicting Oil ProductionOil production is increasing, but more slowly than in the past.Oil reserves – oil deposits that can be extracted profitably at current prices using current technology.All predictions of future oil production are guided by an important principle:The relative cost of obtaining fuels influences the amount of fossil fuels that we extract from the Earth.i.e. as supply decreases, we may rely on other sources.
20 Fossil Fuels and the Future Future Oil ReservesNo large oil reserves have been discovered recently.Deep-ocean may be tapped in the future.Many issues.Think of the BP oil spill in the Gulf…