PASSAGE 1
At the moment, we get about 70% of our energy from fossil fuels like oil, coal and natural gas. But there are two main problems with fossil fuels. Firstly, they release CO₂ when we burn them. And secondly, fossil fuels take millions of years to form and the supply is limited.
But fossil fuels are not the only sources of energy. Alternative energy is energy generated from any source other than ‘traditional’ fossil fuels and which doesn’t damage our environment. The sun (solar energy), wind (eolic energy), water (hydroelectric energy), tides and waves (tidal and wave power) are all alternative energy sources. They are also called renewable energies because they won’t run out.
There are other sources of energy such as biofuel and nuclear power, but these are not strictly alternative energy sources. Biofuel is a term that includes a wide variety of fuels obtained from biomass (carbon-based biological material, usually plants), so it releases CO₂ in the same way as fossil fuels. Nuclear power doesn’t produce CO₂, but it does produce waste which can stay toxic for 240,000 years.
Alternative energy is also classed as sustainable energy – this means we can use it now without affecting the supply in the future. Biofuels can also be sustainable, but only when the biological material is used more slowly than it grows. Climate change and global warming, together with high oil prices and the risk of nuclear contamination, are making renewable energy sources more and more attractive. The production of alternative energy is growing very rapidly, particularly in Europe, Asia, and the United States. It is estimated that 16% of all energy now comes from renewable resources.
(Adapted from tieng Anh 12 – Think)
