1. Energy Types

2. What are our main energy sources?
Industrialised countries need large amounts of energy
Most of this energy comes form fossil fuels which are burnt in power stations, factories, homes and vehicles
These fossil fuels formed millions of years ago, and are non-renewable
Once the fossil fuels have been used up there will be no more to replace them

3. Problems with burning fossil fuels
Huge amounts of carbon dioxide are given off into the atmosphere
Carbon dioxide causes global warming or the greenhouse effect
coal-burning power stations also give off sulphur dioxide gas which leads to acid rain

4. What is the greenhouse effect?
Carbon dioxide gas acts like the glass in a greenhouse
Infrared radiation from the Sun is usually reflected back into space
Greenhouse gases stop this, and heat is reflected back to the Earth again

5. What are the problems with global warming?
The average temperature of the Earth will rise
This can lead to droughts

6. Extremes of weather will occur hurricanes and storms

7. The increase in temperature will speed up the melting of the polar ice caps

8. Global warming will therefore lead to floods

9. So all this burning of fossil fuels leading to an Earth that is suffering form many environmental problems

10. Other problems from the pollution from burning fossil fuels:
Dust and gases in the air can lead to smog above large industrialised cities
A hole is developing in the ozone layer which therefore will not filter out harmful ultra-violet rays from the Sun

11. We need to conserve our fossil fuels
The electricity we produce from burning fossil fuels could also be made using renewable energy resources
It makes sense to save the oil we have left for making fuel for transport and for making plastics
We could try to save wasting energy from fossil fuels during domestic use in our homes and from waste transport consumption of fuel

12. Alternative energy sources
Wind energy
Hydroelectric energy
Solar energy
Nuclear energy
Geothermal energy
Biomass energy

13. Problems with nuclear fuels
Nuclear power stations can produce large amounts of energy from small amounts of nuclear fuel. (Radioactive materials naturally release heat)
Nuclear radiation is extremely dangerous
High safety standards are needed
Waste materials stay radioactive for thousands of years
There have been some disastrous accidents at nuclear power stations which have affected all living things in the area

14. Advantages of nuclear fuels
Low Pollution: Nuclear power also has a lot fewer greenhouse emissions. 
Low Operating Costs: Nuclear power produces very inexpensive electricity.
Reliability: It is estimated that with the current rate of consumption of uranium, we have enough uranium for another years. 

15. Problems with wind energy
The strength of the wind is not constant and it varies from zero to storm force. This means that wind turbines do not produce the same amount of electricity all the time.
Wind turbines are noisy. Each one can generate the same level of noise as a family car travelling at 70 mph.
Large wind farms are needed to provide entire communities with enough electricity. 

16. Advantages of wind energy
The wind is free and with modern technology it can be captured efficiently.
Once the wind turbine is built the energy it produces does not cause green house gases or other pollutants.
Wind turbines are available in a range of sizes. Single households to small towns and villages can make good use of range of wind turbines available today.

17. Problems with hydroelectric energy
Hydroelectric plants are very expensive to build, and must be built to a very high standard. The high cost means that plants must operate for a long time to become profitable.
The creation of dams can also create flooding of land, which means natural environment and the natural habitat of animals, and even people, may be destroyed.
The building of dams for hydroelectric power can also cause a lot of water access problems. The creation of a dam in one location may mean that those down river no longer have control of water flow. This can create controversy in places where neighboring countries share a water supply.

18. Advantages of hydroelectric energy
Hydroelectric power can be created 24/7 indefinitely assuming that the body of water it is utilizing never runs dry.
It is also another absolutely clean source of energy. The power plants, once in place, do not create any waste byproducts in their conversion.
Dams constructed can also shut their gates and conserve the water for use when power is in higher demand.

19. Problems with solar energy
The primary disadvantage of is that it obviously cannot be created during the night. The power generated is also reduced during times of cloud cover
Solar panel energy output is maximized when the panel is directly facing the sun. This means that panels in a fixed location, such as the building above, will see a reduced energy production when the sun is not at an optimal angle.
Even todays most efficient solar cells only convert just over 20% of the suns rays to electricity. With increased advances in solar cell technology this number is likely to increase.
solar panels can be a substantial initial investment. However, the cost of solar panels incurred is only the initial cost, after buying and installation they create free energy for use.

20. Advantages of solar energy
it is indefinitely renewable (at least until the sun runs out in billions of years).
Solar panels are also a silent producer of energy
The federal government has also introduced generous tax credits for individuals and companies that invest in solar

21. Problems with biomass energy
Inefficient as Compared to Fossil Fuels. Ethanol, as a biodiesel is inefficient when compared to gasoline, and it often has to be mixed with some gasoline to make it work properly anyway.
Harmful to Environment because it increases methane gases, which are also harmful to the Earth’s— ozone layer.

22. Advantages of biomass energy
Reduces need for fossil fuels for the production of heat, steam, and electricity for residential, industrial and agricultural use.
 Always available and can be produced as a renewable resource.
Growing Biomass crops produce oxygen and use up carbon dioxide.
The use of waste materials reduce landfill disposal and makes more space for everything else.
Less money spent on foreign oil

23. Problems with geothermal energy
You’ll need a location that offers the right kind of hot rocks. Volcanic areas often provide the most geothermal efficiency.
sometimes a geothermal site might run out of steam. And when this happens, the dry spell may last for periods that reach into the decades
A potential danger are the hazardous gases and minerals can seep up from beneath the ground, and safe disposal of them may prove very difficult and dangerous.

24. Advantages of geothermal energy
geothermal energy is renewable, meaning that as long as we don’t pump too much cold water into the earth -cooling off the hot
doesn’t produce pollution, and at the same time, it doesn’t contribute to the greenhouse effect!
The power stations for don’t take up a bunch of room, and they tend to have less of an impact on the surrounding environment.