Alternative energy sources

       The question of energy has two main aspects: type of energy used and amount of energy used. Modern approaches to energy supply are based on nonnuclear, renewable energy sources and more effective use of energy, through either improved technology or reduced energy consumption.

The earth’s biggest problem today is energy. We normally use four things to make electricity: oil, coal, gas or nuclear power. All of these produce terrible pollution problems. Nuclear power leaves dangerous radioactive waste. The others all produce gases- and these gases cause acid rain and the greenhouse effect.

- Geothermal energy: The centre of the Earth is very hot. In some places that heat is not too far below the ground. We can pump cold water down into the hot rocks, and get hot water back. From this hot water we get steam to make electricity.

- Biofuels are produced from living organisms or from metabolic by-products (organic or food waste products). In order to be considered a biofuel the fuel must contain over 80 per cent renewable materials. Unlike other renewable energy sources, biomass can be converted directly into liquid fuels - biofuels - for our transportation needs (cars, trucks, buses, airplanes, and trains). The two most common types of biofuels are ethanol and biodiesel.

Advantages of alternative energy:

·       It is renewable (will never run out)

·       not harmful for environment

·       renewable energy can create new jobs and promote economic development

Disadvantages are: 

solar energy  -- panels are expensive. Most governments are not all willing to buy home generated electricity. Not all climates are suitable for solar panels. 

wind energy -- turbines are expensive. Wind doesn't blow all the time, so they have to be part of a larger plan. 

hydro-power -- dams are expensive to build and disrupt the environment.

geothermal energy -- difficult to drill two or three kilometers down into the earth.

biofuel -- often uses crop land or crops (like corn) to produce biofuel so the price of cheap food goes up.