3. How does is work?-
Like coal
GAS
1. Advantages:-
- Burns clean compared to cola, oil (less polluting)
- 70% less carbon dioxide compared to other fossil fuels
- helps improve quality of air and water (not a pollutant)
2. Disadvantages:-
- not a renewable source
- finite resource trapped in the earth (some experts disagree)
- inability to recover all in-place gas from a producible deposit because of unfavorable economics and lack of technology (It costs more to recover the remaining natural gas because of flow, access, etc.)
3. How does it work:-
Gas is similarly produced and works just like coal and gas.
Uranium 235
1. Advantages:-
- Fuel can be recycled
- Low cost power for today’s consumption
- Viable form of energy in countries that do not have access to other forms of fuel
2. Disadvantages:-
- Contamination of the environment (long term)
- Useful lifetime of a nuclear power plant
- Plant construction is highly politicized
3. How does it work:-
Nuclear power is generated using Uranium, which is a metal mined in various parts of the world. Nuclear power produces around 11% of the world's energy needs, and produces huge amounts of energy from small amounts of fuel, without the pollution that you'd get from burning fossil fuels.
WIND
1. Advantages:-
- Does not add to thermal burden of the earth
- Produces no health-damaging air pollution or acid rain
- Land can be sued to produce energy and grow crops simultaneously
2. Disadvantages:-
- For most locations, wind power density is low
- Wind velocity must be greater than 7 mph to be usable in most areas
- Problem exists in variation of power density and duration (not reliable)
3. How does it work:-
The Sun heats our atmosphere unevenly, so some patches become warmer than others. These warm patches of air rise, other air blows in to replace them - and we feel a wind blowing.We can use the energy in the wind by building a tall tower, with a large propellor on the top. The wind blows the propellor round, which turns a generator to produce electricity.
WAVES
1. Advantages:-
- The energy is free - no fuel needed, no waste produced.
- Not expensive to operate and maintain.
- Can produce a great deal of energy.
2. Disadvantages:-
- Depends on the waves - sometimes you'll get loads of energy, sometimes nothing.
- Needs a suitable site, where waves are consistently strong.
- Some designs are noisy.
3. How it works:-
At a wave power station, the waves arriving cause the water in the chamber to rise and fall, which means that air is forced in and out of the hole in the top of the chamber. We place a in this hole, which is turned by the air rushing in and out. The turns a generator.
TIDAL
1. Advantages:-
- Not expensive to maintain.
- Tides are totally predictable.
- Offshore turbines and vertical-axis turbines are not ruinously expensive to build and do not have a large environmental impact.
2. Disadvantages:-
- A barrage across an estuary is very expensive to build, and affects a very wide area.
- Only provides power for around 10 hours each day, when the tide is actually moving in or out.
- Flooding of available land that could be used for agriculture
3. How it works:-
These work rather like a scheme, except that the dam is much bigger. A huge dam (called a "barrage") is built across a river estuary. When the tide goes in and out, the water flows through tunnels in the dam. The ebb and flow of the tides can be used to turn a , or it can be used to push air through a pipe, which then turns a . Large lock gates, like the ones used on canals, allow ships to pass.
HYDROELECTRICAL
1. Advantages:-
- Water can be stored above the dam ready to cope with peaks in demand.
- Hydro-electric power stations can increase to full power very quickly, unlike other power stations.
- Electricity can be generated constantly.
2. Disadvantages:-
- The dams are very expensive to build.
However, many dams are also used for flood control or irrigation, so building costs can be shared.
- Building a large dam will flood a very large area upstream, causing problems for animals that used to live there.
- Finding a suitable site can be difficult - the impact on residents and the environment may be unacceptable.
3. How does it work?
A dam is built to trap water, usually in a valley where there is an existing lake. Water is allowed to flow through tunnels in the dam, to turn and thus drive generators.
SOLAR
1. Advantages:-
- Solar energy is free - it needs no fuel and produces no waste or pollution.
- In sunny countries, solar power can be used where there is no easy way to get electricity to a remote place.
- Handy for low-power uses such as solar powered garden lights and battery chargers
2. Disadvantages:-
- Doesn't work at night.
- Very expensive to build solar power stations.
Solar cells cost a great deal compared to the amount of electricity they'll produce in their lifetime.
- Can be unreliable unless you're in a very sunny climate. In the United Kingdom, solar power isn't much use except for low-power applications, as you need a very large area of solar panels to get a decent amount of power. However, for these applications it's definitely worthwhile.
3. How does it work?
Solar Cells (really called "photovoltaic" or "photoelectric" cells) that convert light directly into electricity.
Solar water heating, where heat from the Sun is used to heat water in glass panels on your roof. Water is pumped through pipes in the panel.
The pipes are painted black, so they get hot when the Sun shines on them.
GEOTHERMAL
1. Advantages:-
- Geothermal energy does not produce any pollution, and does not contribute to the greenhouse effect.
- The power stations do not take up much room, so there is not much impact on the environment.
- No fuel is needed.
2. Disadvantages:-
- The big problem is that there are not many places where you can build a geothermal power station. You need hot rocks of a suitable type, at a depth where we can drill down to them. The type of rock above is also important, it must be of a type that we can easily drill through.
- Sometimes a geothermal site may "run out of steam", perhaps for decades.
- Hazardous gases and minerals may come up from underground, and can be difficult to safely dispose of.
3. How does it work?
Hot rocks underground heat water to produce steam. We drill holes down to the hot region, steam comes up, is purified and used to drive turbines, which drive electric generators.
There may be natural "groundwater" in the hot rocks anyway, or we may need to drill more holes and pump water down to them.
BIOMASS
1. Advantages:-
- It makes sense to use waste materials where we can.
- The fuel tends to be cheap.
- Less demand on the Earth's resources.
2. Disadvantages:-
- Collecting the waste in sufficient quantities can be difficult.
- We burn the fuel, so it makes greenhouse gases.
- Some waste materials are not available all year round
3. How does it work?
The fuel is burned, which heats water into steam, which turns turbines, which in turn drive generators, just like in a fossil-fuel power station.