Energy resources BY DANIEL, CHRIS, YOHANA AND SANDRA

Wind power  Conversion of wind energy into useful form of energy  Wind turbines make electrical power [how?] Pros:  Renewable and sustainable  Relatively cheap and the costs continue to decrease – the energy is practically free once the infrastructure is paid for  Reduced greenhouse gas emissions and fossil fuel depletion Cons:  No wind – no energy  Local disadvantages: land use, noise, visual pollution, impact on night-time temperatures and weather  Wildlife impact. Not only birds, but bats have experienced fatalities. Qins ryevubwa

Biofuels  Fuel from recently lifeless or living biological matter  Usually used to power cars, heat homes and for cooking  Two common ways of producing the liquid and gas version:  Growing crops that are high in sugar (e.g. sugar cane) or starch (e.g. corn) and then using yeast to produce ethanol  Growing plants that contain high amounts of vegetable oil (e.g. oil palm, soybean, algae); when they are heated their viscosity (explain) is reduced and they can be burned in a diesel engine or they can be chemically processed to produce fuels such as biodiesel

Pros:  Renewable  Clean  Inexpensive  Flexible  Additives  Carbon neutral pros-and-cons/ pros-and-cons/ good website to explain each in class Cons:  Food vs. Biofuels  Loss of habitat  Limitation in its use in vehicles

Wastes  Organic waste decomposes and gives off methane gas which can be burned  Burned directly to generate energy (some example)

Pros:  the majority of waste that would normally go into landfill sites can be re-used.  the fuel is obtainable cheaply.  there will always be a reliable source of fuel as people will always have waste.  current landfill sites can be mined out and the landfill material used as fuel. Cons:  the public at large is still unconvinced that emissions from waste-to-energy plants are clean and free from harmful chemicals.  waste-to-energy facilities are expensive to construct (...but so are landfill sites)  Burning adds to global warming gases in the atmosphere (however decomposition of the waste would do this in any case)

Geothermal energy  Energy is obtained from residual heat in the ground 1. Water is pumped into pipes beneath the ground 2. Geothermal heat from the ground heats the water 3. Water is used to heat buildings

Pros:  almost entirely emission free.  zero carbon.  no fuel required.  smallest land footprint of any major power source.  limitless supply.  simple and reliable.  cost competitive in some areas.  can be built underground. Cons:  prime sites are often far from population centers.  losses due to long distance transmission of electricity.  water usage.  high construction costs.  drilling into heated rock is very difficult.  very high temperature required.