Renewable energy versus conventional energy. The myths are abundant and grow like vegetables in a greenhouse. Take a hike through the carbon jungle and find out what’s right or wrong.
Myth 1: solar power is too expensive to be of much use.
Today’s bulky and expensive solar panels capture only 10 per cent or so of the sun’s energy, but rapid innovation in the US means that the next generation of panels will be much thinner, capture far more energy and cost a fraction of what they do today. First Solar, the largest manufacturer of thin panels, claims its products will generate electricity in sunny countries as cheaply as large power stations by 2012.
Myth 2: wind power is too unreliable.
During some periods in 2008 the wind provided almost 40 per cent of Spain’s power. Parts of northern Germany generate more electricity from wind than they actually need. Northern Scotland could easily generate 10 or even 15 per cent of the UK’s needs for electricity at a cost that would comfortably match today’s fossil fuel prices.
Myth 3: marine energy is a dead-end.
Designing and building machines that can survive the harsh conditions of fast-flowing ocean waters has been challenging and the past decades have witnessed repeated disappointments. In 2008, however, Britain has seen the installation of the first tidal turbine to be successfully connected to the UK electricity grid in Strangford Lough, Northern Ireland, and the first group of large-scale wave power generators have been installed 5 km off the coast of Portugal.
Myth 4: nuclear power is cheaper than other low-carbon sources of electricity.
The new nuclear power station on the island of Olkiluoto in western Finland is a clear example of the high and unpredictable cost of nuclear plants. Electricity production was supposed to start in 2008, but the latest news is that the power station will not start generating until 2012. The impact on the cost of the project has been dramatic. When the contracts were signed, the plant was supposed to cost €3bn. The final cost is likely to be more than twice this figure. A second new plant in Normandy appears to be experiencing similar problems. In the US, power companies are backing away from nuclear because of fears over uncontrollable costs.
Myth 5: electric cars are slow and ugly.
We are very close to developing electric cars that match the performance of conventional vehicles. The Tesla electric sports car, sold in America but designed by Lotus in Norfolk, amazes all those who experience its awesome acceleration. With a price tag of more than $100,000, late 2008 probably wasn't a good time to launch a luxury electric car. But the Tesla has demonstrated to everybody that electric cars can be both exciting and desirable.
Myth 6: biofuels are always destructive to the environment.
Making some of our motor fuel from food has been an almost unmitigated disaster. It has caused hunger and increased the rate of forest loss, as farmers have sought extra land on which to grow their crops. However the failure of the first generation of biofuels should not mean that we should reject the use of biological materials forever. Within a few years we will be able to turn agricultural wastes into liquid fuels by splitting cellulose, the most abundant molecule in plants and trees, into simple hydrocarbons.
Myth 7: climate change means we need more organic agriculture.
Most studies show that yields under organic cultivation are little more than half what can be achieved elsewhere. Unless this figure can be hugely improved, the implication is clear; the world cannot feed its people and produce huge amounts of cellulose for fuels if large acreages are converted to organic cultivation.
Myth 8: zero carbon homes are the best way of dealing with greenhouse gas emissions from buildings.
Buildings are responsible for about half the world's emissions, and domestic housing is the most important single source of greenhouse gases. But making a building genuinely zero carbon is extremely expensive, and just focusing on the about 1 per cent of the housing stock that is newly built each year has no effect on the remaining 99 per cent. In Germany a mixture of subsidies, cheap loans and exhortation is succeeding in getting hundreds of thousands of older properties eco-renovated each year to very impressive standards and at reasonable cost.
Myth 9: the most efficient power stations are big.
New types of tiny combined heat and power plants are able to turn about half the energy in fuel into electricity, almost matching the efficiency of huge generators. These are now small enough to be easily installed in ordinary homes. Not only will they generate electricity but the surplus heat can be used to heat the house, meaning that all the energy in gas is productively used. Some types of air conditioning can even use the heat to power their chillers in summer.
Myth 10: all proposed solutions to climate change need to be hi-tech.
The advanced economies are obsessed with finding hi-tech solutions to reducing greenhouse gas emissions. Many of these are expensive and may create as many problems as they solve. Nuclear power is a good example. But it may be cheaper and more effective to look for simple solutions that reduce emissions, or even extract existing carbon dioxide from the air.
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