Eco-friendly energy
Mr Blair's mounting enthusiasm for nuclear power threatens to derail his Government's commitment to less familiar but "greener" energy strategies - "carbon capture" and microgeneration, in particular. Are those the strategies we should really be concentrating on?
Does the UK face an energy crisis?
Only in so far as we are soon going to become far more dependent on imported gas, unless we take steps to do something about it. Roughly half the gas used in Britain today goes to heat homes and businesses, the other half to generate electricity. (Some 40% of our electricity comes from gas-fired power stations.) Given that our reserves of North Sea gas are dwindling while our demand for electricity is expected to rise 15% in the next 15 years; given also that our ageing nuclear power stations and heavily polluting coal-fired ones (which together provide about 30% of our electricity) are to be phased out during that same period, it seems inevitable that we're going to have to rely increasingly on gas coming from abroad.
Is that such a problem?
Not necessarily. Much of the extra gas would come from Russia, but that is less of a threat than sometimes implied, since Russia is at least as dependent on Western revenues as we are on its gas. In any case the biggest supplier of gas to the UK now and (with a vast new pipeline in the offing) in future, is Norway - a notably stable regime. Nonetheless, it's not a good idea to be over-reliant on just one form of energy: you need a hedge should something go wrong. And that aside, there is the key issue of greenhouse gas emissions. Labour's target is that by 2010 they should be 20% less than levels in 1990; yet since Labour came to power, levels of C02 have risen. Nuclear is the answer, Blair now seems to be saying.
Why do green campaigners say it isn't the answer?
For a start our energy consumption - and its emission of greenhouse gases - doesn't just involve electricity. Our home heating tends increasingly to be based on gas, so that here nuclear power will be of no help at all unless we rip out our gas boilers and switch to electric. Besides it takes at least 15 years from planning process to completion before a new nuclear power station is operative. Hence, for many environmentalists, the emphasis on nuclear, with its highly centralized distribution systems and its many attendant risks, simply distracts attention from the need to invest in forms of "green" energy that we can use in the next critical decade.
What forms are these?
One key technology is "carbon capture". This involves removing carbon dioxide from coal - either before or after the coal is burnt, there are two distinct technologies - and then sending the C02, via pipeline, to oil or gas rigs, whence it's pumped underground into spaces which were once filled with fossil fuels. The huge advantage of this is that it would give rise to "clean" coal power stations, and enable Britain to exploit its own plentiful coal reserves while helping to meet C02 emission targets.
Is this a feasible strategy?
Technologies of carbon "capture" are relatively advanced but haven't yet been deployed to generate electricity. The techniques of storing the CO2 are also well-advanced: for example, the Norwegian company Statoil, has been pumping CO2 into a sandstone layer under the North Sea for years. (There is enough space under the North Sea to store Europe's entire carbon output for between 70 to 200 years.)
Then what are the drawbacks?
Some fear that if badly managed, leakage could occur. But the real problem lies in the extra cost that carbon capture (like any "clean" technology") entails, and the political willingness to get people to pay for it. However, since the world (with India and China at the forefront) plans to build 1,400 new coal-fired stations between now and 2030 - stations which, "uncleaned", would add as much carbon to the atmosphere as has been added since the dawn of the industrial revolution - we all have a strong latent interest in underwriting "clean coal" technologies.
Aren't there any smaller-scale solutions on offer?
Yes. In March the Government published a "microgeneration strategy" which envisages homes and businesses producing green energy for their own use and selling the excess to the National Grid. This, in theory, would cut both fuel bills and C02 emissions. Producing on such a small scale, say proponents, would bypass the many planning constraints that have dogged construction of big commercial wind farms. And since micro-power produces electricity at the point of use, there's no need for large-scale grid connections and the 10% losses in transmission associated with big power plants. In this year's budget, Gordon Brown announced an extra £50m for grants to install microgeneration in homes, schools and other public buildings.
So why aren't more people converting to micro-power?
Again the main problem is cost. Even with government grants, buying, say, a wind turbine or a photovoltaic [solar electric] panel for home use remains expensive: it would take years for the average household to recoup the outlay from lower energy bills. A rooftop windmill of the sort installed by David Cameron would cost £1,500 and even the manufacturers, Windsave, say it could produce as little as 500kWh of electricity per year - hardly the 35% of a household's electricity needs that is often claimed for such technology.
So what's to be done?
In principle, householders could recoup some of the cost of these investments if they were able to sell back any surplus they generate. In Germany, which has a booming industry in photovoltaic panels, most such panels, whether for homes or businesses, connect to the grid. By 2015 Germany expects to generate 12 GW of electricity from photovoltaic - exactly the amount we are scheduled to get from nuclear by 2020. The question is this: who will have something to sell the world 15 years from now... us or the Germans?
Microgenerate: make your own power
Solar water heating systems: These cost between £2,000 and £3,000 and (it's claimed) provide enough hot water to meet half of a household's needs, with savings of £50 a year. A grant of £400 is available.
Photovoltaic (PV) systems convert the sun's radiation into electricity. These start at £6,000 and grants of up to 50% are available. Promoters say they can cut as much as 50% off electricity bills.
Domestic wind turbines: These cost from around £1,300 and are claimed to provide up to 35% of the average home's electricity needs, though planning permission is needed to install them.
Ground Source Heat Pumps transfer energy from the ground into a long, fluid-filled pipe buried under the garden which is then used to make hot water and underfloor heating. They can provide up to 80% of a household's hot water and heating needs and cost from £6,000. A grant of £1,200 is available.
Micro-combined heat and power units operate like conventional hot water boilers but use excess heat to generate electricity, for home use or for sale to the National Grid. They cost £3,000 and can cut bills by £120 a year. No grants available.
Biomass heating uses wood chips in stoves, or boilers, connected to central heating systems.
Source: http://www.martinfrost.ws/htmlfiles/june2006/ecofriendly_energy.html
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