14-11-2012, 05:40 PM
Energy and conservation
Energy and conservation.ppt (Size: 1.09 MB / Downloads: 104)
What are our main energy sources?
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
Industrialised countries need large amounts of energy
Oil is useful for other things too
Oil is a mixture of different compounds
We can separate these substances by a process called fractional distillation
These fractions include fuels like petrol, diesel and aviation fuel
Parts of oil are also used to make plastics, medicines, paints, dyes and even wax candles
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
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