This has probably been posted before, but what the hell:
Energy: the answer is not blowing in the wind | spiked
"John Hutton, the UK business secretary, announced plans yesterday to increase Britain’s production of electricity from wind. According to Hutton, by 2020 the UK will produce 33 gigawatts (GW) from wind power, mainly from offshore turbines, apparently capable of powering 25million homes (1). But actually producing that much electricity from wind is unrealistic, a distraction from the only serious and viable method of producing low carbon, reliable electricity: nuclear.
The reaction of environmentalists to these developments shows how apparently strong principles can be set aside in favour of certain right-on technologies. Try to sink one 15,000 tonne oil platform in the North Sea (as Shell attempted with the Brent Spar platform in 1995) and Greenpeace will vilify you, but announce a plan to plant 7,000 concrete and steel pylons - each weighing 2,000 tonnes - on the seabed and you will be an eco-hero. Pour 60million tons of concrete across the Severn Estuary to build an energy-generating tidal barrage and Sir Jonathon Porritt and his Sustainable Development Commissioners will carry you in triumph through Jerusalem.
The Severn Barrage, essentially a dam across the Severn Estuary to generate power from its 10-metre tides, is equally loved and hated by greens. It will never be built. But, to universal green approval, John Hutton has offered up Britain’s entire continental shelf for industrialisation on a scale that makes the Brent Spar look like as biodegradable as an organic ciabatta.
According to Hutton, ‘Next year we will overtake Denmark as the country with the most offshore wind capacity. This could be a major contribution towards meeting the EU’s target of 20 per cent of energy from renewable sources by 2020.’ The key word in Hutton’s statement is ‘capacity’ because, although it is always claimed that Denmark gets 20 per cent of its electricity from wind power (2), in fact the Danish experience shows that investment in wind is a grandiose and expensive folly – guaranteed neither to supply electricity nor reduce greenhouse emissions.
Denmark’s wasted wind
Most of Denmark’s wind generation is off the west coast, where the electrical grid is better integrated with Norway than with the rest of the country. East Denmark is integrated with Sweden and Germany. Central generation is mostly from coal stations and there are over 700 local combined heat and power (CHP) stations running on gas or biofuel. CHP stations generate electricity and use what would otherwise be wasted heat to supply hot water to surrounding communities (3).
Because wind generation is immensely erratic and hard to forecast it is almost impossible to incorporate it into the grid without compromising reliability. Detailed study of inflow and outflow between Germany and Scandanavia demonstrates that as much as 84 per cent of west Denmark’s wind power is exported to Norway (at a loss to Danish consumers of about £100million) (4). Norway’s electrical supply is 100 per cent hydro, generated by water falling through turbines in river dams, and the Danish wind power is simply used to pump water back up into reservoirs – in effect, storing the electricity (and currently the only practical way to store power). Hydro and wind are extremely complementary, but the people of Denmark are paying the compliment and the people of Norway being flattered.
Currently, the Danish Wind Industry Association (DWIA) admits: ‘Danish wind power only contributes to adequacy [of supply] with a capacity value of zero.’ That is, wind’s generating capacity does not guarantee any of the basic and essential electrical supply. When wind production increases to a 50 per cent ‘share’ (in 2025), according to some DWIA projections, Denmark will have to export unusable excess power at a large economic loss but neighbouring countries will make a profit by selling back essential baseload electricity.
Even when electricity generation from wind farms is stable, its unpredictability means it cannot prevent the burning of coal at slow-responding coal stations. Instead, because it comes at very low marginal cost, it replaces more expensive electricity supplied by the slightly adaptable CHP stations. But since domestic and industrial customers rely on those same CHP stations for hot water, the stations must keep running, burning fuel in the process. By not producing and selling electricity as this hot water is produced, the CHP stations become less economically viable.
Paradoxically, such CHP stations are an essential component of Britain’s ‘alternative energy future’. CHP represents the ‘decentralised microgeneration’ beloved by the Sustainable Development Commission (SDC), an environmental quango that advises the UK government, which wants a future of ‘self-sustaining local communities’. A massive expansion of wind power in the UK will make CHP much less attractive by undercutting the price of electricity and forcing CHP stations to turn on and off – making them both environmentally and economically inefficient. In 2004, partly for such reasons, Elsam (then the power generation company for west Denmark) told a meeting of the DWIA and Danish government that increasing wind power does not decrease CO2 emissions – because it forces CHP stations to run with less carbon-efficiency. A 2003 study by the Tallinn Technical University in Estonia showed that trying to incorporate wind with CHP can actually increase fuel consumption and emissions by eight to 10 per cent - completely eliminating any CO2 benefits from wind (5).
So, the wind power Denmark sells to Norway for use in hydro stations saves not one molecule of CO2 and by interfering with CHP stations may actually make emissions worse. In east Denmark, the baseload is regularly topped up from the Swedish grid – half nuclear and half hydro – so Denmark’s total electricity supply is, actually, about nine per cent nuclear.
Wind turbine dominoes
Germany should be another case study for Hutton before he goes too wild on wind. A study of the German national grid for E-On (the largest operator of wind turbines in Germany, with 43 per cent of the total)
shows that as wind generating capacity increases, the proportion of that capacity that can be incorporated into the grid actually decreases. When there are sudden high winds across a large number of turbines, the unexpected excess electricity can overload the system. The more turbines that are connected, the less unrestricted ‘access’ each wind farm can have to the grid and the greater the controls needed to prevent overloads.
Currently, the German grid with its European interconnections acts as a very large sink into which surplus wind-generated electricity can (usually) dissipate, but even so, large new grid extensions and special switching measures are needed to prevent grid overloads when wind power peaks. Consequent supply failures can spread from northern Germany in a loop through the grids of Holland, Poland and the Czech Republic. The potential impact on other countries means that Germany can no longer expand wind farms in isolation but must consider the impact on a wider European level (6).
By 2015, Germany will have 36GW capacity from wind, but only six per cent of that capacity can be considered as guaranteed coverage of maximum seasonal load. And traditional power stations (coal, nuclear, gas) with capacities equal to 90 per cent on the installed wind capacity must be permanently online (7). If that six per cent figure holds true for Britain, Hutton’s 33GW worth of new British wind power would represent only 1.64GW of actual electricity capacity – or about the same as two advanced nuclear power plants.
On rough calculations, building a 33GW offshore wind capacity will use as much concrete and steel as building 78 medium-sized nuclear power plants, which would produce 62.4GW of reliable electricity (opposed to 1.64GW from wind) - not far short of the UK’s entire 75GW demand.
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