Alternative Sources of Energy

Prior to the Industrial Revolution, the sun was the only source of energy widely available to humankind. Wood has been used since prehistory. Sails to use the sun-created wind were first raised 5,000 years ago, windmills 2,000 years later, and water-wheels 2,000 years after that. Coal came into general use just 300 years ago, and oil and gas only in the last 100 years. Not until the 20th century did non-solar energy arrive in the form of nuclear power. The natural flows of energy that have been used for millennia are known as renewable resources. The amount of energy fossil fuels can supply is ultimately limited by geology. These are known as non-renewable sources. As global energy demand grows and non-renewable sources begin to run out, so attention is turning back to the renewables.

Biomass

Biomass energy is plant or animal matter that can be converted into fuel. Nearly half the world’s population relies on biomass, mostly in the form of wood which is the principal fuel for 80% of people in developing countries.

Hydropower

Falling water generates 25% of the world’s electricity, about 5% of total energy demand. Although the most mature of the renewable technologies (over 30% of the developed world’s hydro potential is harnessed), it is still underexploited.

Solar

The sun already contributes significantly to the energy needs of buildings through the walls and windows, but because this energy is free, it is not counted in official statistics. Recent years have seen a massive increase in investment in technologies to make use of the sun’s energy.

Power from the sea

Ocean power comes in four main forms: wave power, tidal power, current power, and ocean thermal energy conversion which exploits temperature differences between surface and depths. The ultimate energy potential is massive, but only a small fraction is likely to be harnessed.

Wind

Winds are caused by uneven heating of the Earth’s surface. Windmills can be used either to generate electricity or to do mechanical work.

1. Why are hydropower, solar, ocean and wind power sometimes called alternative sources of energy?

Text D

Energy Crisis

Professor Marvin Burnham of the New England Institute of Technology: “We are in an energy crisis and we will have to do something quickly. Fossil fuels (coal, oil and gas) are rapidly running out. The tragedy is that fossil fuels are far too valuable to waste on the production of electricity. Just think of all the things you can make from oil! If we don’t start conserving these things now, it will be too late. And nuclear power is the only real alternative. We are getting some electricity from nuclear power stations already. If we invest in future research now, we’ll be ready to face the future. There’s been a lot of protest lately against nuclear power – some people will protest at anything – but nuclear power stations are not as dangerous as some people say. It’s far more dangerous to work down a coal-mine or on a North Sea oil-rig. Safety regulations in power stations are very strict.

If we spent money on research now, we could develop stations which create their own fuel and burn their own waste. In many parts of the world where there are no fossil fuels, nuclear power is the only alternative. If you accept that we need electricity, then we will need nuclear energy. Just imagine what the world would be like if we didn’t have electricity – no heating, no lighting, no transport, no radio or TV. Just think about the ways you use electricity every day. Surely we don’t want to go back to the Stone Age. That’s what will happen if we turn our backs on nuclear research.”

Jennifer Hughes, a member of CANE, the Campaign Against Nuclear Energy: “I must disagree totally with Professor Burnham. Let’s look at the facts. First, there is no perfect machine. I mean, why do airplanes crash? Machines fail. People make mistakes. What would happen if there were a serious nuclear accident? And an accident must be inevitable – sooner or later. Huge areas would be evacuated, and they could remain contaminated with radioactivity for years. If it happened in your area, you wouldn’t get a penny in compensation. No insurance company covers nuclear risks. There are accidents. If the nuclear industry didn’t keep them quiet, there would be a public outcry. Radioactivity causes cancer and may affect future generations.

Next, nuclear waste. There is no technology for absolutely safe disposal. Some of this waste will remain active for thousands of years. Is that what you want to leave to your children? And their children’s children? A reactor only lasts about 25 years. By the year 2000 we’ll have “retired” 26 reactors in the UK.

Next, terrorism. Terrorists could hold the nation to ransom if they captured a reactor. I consider that nuclear energy is expensive, dangerous, and evil, and most of all, absolutely unnecessary.”

Dr. Catherine Woodstock, the author of several books on alternative technology: “We can develop alternative sources of power, and unless we try we’ll never succeed. Instead of burning fossil fuels we should be concentrating on more economic uses of electricity, because electricity can be produced from any source of energy. If we didn’t waste so much energy, our resources would last longer. You can save more energy by conservation than you can produce for the same money. Unless we do research on solar energy, wind power, wave power, tidal power, hydroelectric schemes etc, our fossil fuels will run out, and we’ll all freeze or starve to death. Other countries are spending much more than us on research, and don’t forget that energy from the sun, the waves and the wind lasts for ever. We really won’t survive unless we start working on cleaner, safer sources of energy.”

Charles Wicks, MP, the Minister for Energy: “I don’t agree with some of the estimates of world energy reserves. More oil and gas is being discovered all the time. If we listened to the pessimists (and there are lot of them about) none of us would sleep at night. In the short-term, we must continue to rely on the fossil fuels – oil, coal and gas. But we must also look to the future. Our policy must be flexible. Unless we thought new research was necessary, we wouldn’t be spending money on it. After all, the Government wouldn’t have a Department of Energy unless they thought it was important. The big question is where to spend the money – on conservation of present resources or on research into new forms of power.”