Wednesday 3 December 2008

The 10 big energy myths

Myth 1: solar power is too expensive to be of much use

In reality, today's bulky and expensive solar panels capture only 10% 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 of the energy in the sun's light and cost a fraction of what they do today. They may not even be made of silicon. First Solar, the largest manufacturer of thin panels, claims that its products will generate electricity in sunny countries as cheaply as large power stations by 2012.

Myth 2: wind power is too unreliable

Actually, during some periods earlier this year the wind provided almost 40% of Spanish power. Parts of northern Germany generate more electricity from wind than they actually need. Northern Scotland, blessed with some of the best wind speeds in Europe, could easily generate 10% or even 15% of the UK's electricity needs at a cost that would comfortably match today's fossil fuel prices.

Myth 3: marine energy is a dead-end

The thin channel of water between the north-east tip of Scotland and Orkney contains some of the most concentrated tidal power in the world. The energy from the peak flows may well be greater than the electricity needs of London. Similarly, the waves off the Atlantic coasts of Spain and Portugal are strong, consistent and able to provide a substantial fraction of the region's power. Designing and building machines that can survive the harsh conditions of fast-flowing ocean waters has been challenging and the past decades have seen repeated disappointments here and abroad. This year we have 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 5km off the coast of Portugal, constructed by a Scottish company.

Myth 4: nuclear power is cheaper than other low-carbon sources of electricity

If we believe that the world energy and environmental crises are as severe as is said, nuclear power stations must be considered as a possible option. But although the disposal of waste and the proliferation of nuclear weapons are profoundly important issues, the most severe problem may be the high and unpredictable cost of nuclear plants.

Myth 5: electric cars are slow and ugly

We tend to think that electric cars are all like the G Wiz vehicle, with a limited range, poor acceleration and an unprepossessing appearance. Actually, we are already very close to developing electric cars that match the performance of petrol 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 exciting and desirable. The crucial advance in electric car technology has been in batteries: the latest lithium batteries - similar to the ones in your laptop - can provide large amounts of power for acceleration and a long enough range for almost all journeys.

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. Chemists have struggled to find a way of breaking down this tough compound cheaply, but huge amounts of new capital have flowed into US companies that are working on making a petrol substitute from low-value agricultural wastes.

Myth 7: climate change means we need more organic agriculture

The uncomfortable reality is that we already struggle to feed six billion people. Population numbers will rise to more than nine billion by 2050. Although food production is increasing slowly, the growth rate in agricultural productivity is likely to decline below population increases within a few years. The richer half of the world's population will also be eating more meat. Since animals need large amounts of land for every unit of meat they produce, this further threatens food production for the poor. So we need to ensure that as much food as possible is produced on the limited resources of good farmland.

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; domestic housing is the most important single source of greenhouse gases. The UK's insistence that all new homes are "zero carbon" by 2016 sounds like a good idea, but there are two problems. In most countries, only about 1% of the housing stock is newly built each year. Tighter building regulations have no effect on the remaining 99%. Second, making a building genuinely zero carbon is extremely expensive. The few prototype UK homes that have recently reached this standard have cost twice as much as conventional houses.

Myth 9: the most efficient power stations are big

Large, modern gas-fired power stations can turn about 60% of the energy in fuel into electricity. The rest is lost as waste heat.

Even though 5-10% of the electricity will be lost in transmission to the user, efficiency has still been far better than small-scale local generation of power. This is changing fast.


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. There are many viable proposals to do this cheaply around the world, which also often help feed the world's poorest people. One outstanding example is to use a substance known as biochar to sequester carbon and increase food yields at the same time.

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