In the second of a three-part series on the proposed Viking Energy windfarm, PAUL RIDDELL asks whether wind power is a reliable source of electricity and whether it is likely to be harmful to human health. Part three will appear next week.
IF THE government accepts the recommendations of the new committee on climate change published this week – and there is every sign that it will – the demand for sources of renewable energy in Britain is likely to mushroom even further.
The committee, led by Lord Turner, wants a tougher target for greenhouse gas emissions: instead of a cut to 60 per cent below 1990 levels by 2050, it wants an 80 per cent reduction. Given that on some measures emissions in Britain have slowly been rising, that is a tall order; one that will involve an abrupt volte-face on new coal plants such as Kingsnorth in Kent, rapid progress in the construction of new nuclear power stations in England – and more windfarms.
Opponents of windfarms love to claim that they are poor sources of electricity because the wind does
not always blow, leading to load variations on power grids that cause havoc, requiring back-up from more conventional power plants; and anyway they are only built because they are subsidised.
Furthermore, some say, there are now too many windfarms, and if the Viking Energy and interconnector project goes ahead we will ultimately be forced to sell electrictity to the national grid at cut price.
Yet wind power generation around the world is growing at 30 per cent a year and global capacity this year will exceed 100 gigawatts – that’s the equivalent of 100 very large power stations. The world’s largest windfarm, designed to generate a gigawatt, is about to be built for $2 billion in Texas.
Global demand for electricity is growing too. Current consumption is around 15 terawatts (1,000 gigawatts). That figure, experts estimate, will reach 30 terawatts by 2050.
Of course windfarms can only be part of a mix of different sources of electricity, including conventional ones, and increasingly attention is being paid both commercially and politically to tidal and wave energy. But they are not mutually exclusive, as some critics of wind power seem to think.
The big advantage wind turbines have is that technologically they are by far the most advanced. Borrowing from aircraft design, engineers now use sophisticated materials and variable-geometry blades that can flex when the wind gets too strong, “spill” that wind and continue turning. The larger the blades, the more power, hence Viking’s proposed 55m blade length atop 90m towers.
The scientist Albert Betz calculated early last century that the theoretical maximum efficiency of a wind turbine was 59.3 per cent. The new technology gets close to that. The 3.68 megawatt Burradale windfarm outside Lerwick has an average efficiency of 52 per cent (in 2005 it averaged 57.9 per cent, a world record), giving at least technical logic to the plans for a 554 megawatt windfarm in north central Shetland.
Windfarms are more expensive to build than conventional power plants but do not require continued expenditure on an often expensive source of fuel. And obviously the more efficient the windfarm the cheaper the power.
Wind power is subsidised in the UK through Renewables Obligation Certificates (ROCs), which means it can compete in price terms with electricity generated from natural gas. Electricity from coal is still the cheapest; yet if coal-fired power stations were subjected to a carbon tax or forced to capture and store carbon dioxide emissions, the price would soon rise.
Billy Fox, of Sustainable Shetland, observes that recent proposals to pay out more in ROCs to tidal and wave power projects suggest wind power may be losing its place as the front runner among renewable energy sources.
Equally, it may reflect the feeling in government that more needs to be done to “incentivise” technological development in these other, less-well developed fields because wind power is already “up and running”.
The complaint about subsidies seems a moot one. The whole energy sector is a minefield of subsidies and forms of special treatment. A consistent approach would clearly be much better from the consumer’s point of view, but to complain about windfarms because they get subsidies in isolation is false reasoning.
In any case, David Thomson of Viking Energy believes the project could be built without ROCs.
“If a windfarm is viable anywhere, it is viable in Shetland,” he says. “If the market changes and ROCs become less of a feature, there is always going to be a market for renewable energy.
“One of the preconditions of the Viking project is that long-term and sustainable contracts with a firmly agreed pricing structure must be agreed. Without certainty over income guarantee the project will not work. We believe that such is the demand for renewable energy that will be achieved.”
Yet Mr Fox says: “There is more criticism and scepticism coming forward from scientific and industry quarters that wind generation, although having a role to play, cannot be regarded as a primary source of electricity.
“Additionally, we hold the view that renewable energy must play a part in an integrated energy policy. There is a recognised limit of variable renewables such as wind power that can be connected to any electricity grid.
“The level set by the Sustainable Development Commission several years ago was 20 per cent; the Burradale wind farm meets this in the Shetland context. The limiting factor is economic because it relates to the amount of conventional power that must be kept in reserve for when the wind does not blow.
“We do not feel that Shetland should be turned into an offshore windfarm to power mainland UK. We have a very significant opportunity to create in Shetland a policy of community schemes, not necessarily connected to the grid, in conjunction with energy saving measures. These could demonstrate in microcosm how the world should be tackling global climate change.”
<i>The Shetland Times</i> reported two weeks ago that Lerwick power station would have to be replaced, even if the windfarm is built, for security of supply reasons.
Mr Fox believes Sullom Voe power station could supply all of Shetland’s electricity needs for several years to come if it was connected to the local grid south of Voe through an upgrading in the electricity line. (At present, according to official figures, 49 per cent of Shetland’s electricity is supplied by the Lerwick power station, 43 per cent by Sullom Voe and eight per cent by the Burradale windfarm.)
“Prior to the fuel gas pipeline being installed from the west of Shetland there was no guaranteed supply of fuel gas to maximise output from Sullom Voe,” Mr Fox says. “The West Side gas pipeline now provides this. Should the terminal progress to a gas hub for future developments this will extend considerably.
“In addition to the gas turbine capacity of Sullom Voe (in itself capable of supplying both the terminal and Shetland) there is opportunity to use gas turbine exhaust heat currently going to atmosphere through the waste heat boilers and subsequently to steam turbines to provide even more electrical generating capacity.
“Burning fuel gas produces considerably less carbon emissions when compared to heavy fuel oil currently used in the Lerwick power station. Of course these measures do not involve renewables and therefore do not attract ROC. This reflects the government’s blinkered thinking when it comes to implementing measures and appropriate incentives for reduction of carbon emissions.”
AT SETTER, just past Kergord House, in Donnie and Evelyn Morrison’s home the sense of foreboding about the proposed windfarm is palpable.
Evelyn, 54, a medical administrator, suffers from an inoperable brain tumour which has left her partly disabled. In a letter to <i>The</i> <i>Shetland Times</i> earlier this year she described how she would not be able to cope with the “constant flicker and noise and the resulting headaches”. “Even the flicker driving through the trees at Kergord House on a sunny day can provoke a migraine headache,” she wrote.
“It is quite devastating really,” she says as she points out how the windfarm will cover most of the horizon from their home. “It’s not that we are against wind energy, or green energy. It’s just too much right here in the area. I worry about what it is going to do to Shetland. Folk think they are going to get cheaper electricity because of this, and they are not.”
Donnie, 54, a builder, observes: “You are not allowed to put up a house here, yet you can build a massive thing like this that will be visible from space. I think Shetland is so small that the scale of it is totally out of proportion. It would be lost in the wilds of Scotland, but not here.”
He says the justification for the potential financial dividend – £18 million in income for the Charitable Trust and other community benefits – isn’t enough. Shetland, he believes, does not need half of the swimming pools and other community buildings that have been built because only a small group of people benefit. “It has been a case of shout and you shall receive for many many years.”
He fears his land, bought by his grandfather in 1917, will be compulsorily purchased for the interconnector cable. “If I do not agree voluntarily, I will be subject to compulsory purchase. That makes me feel very angry. You feel helpless.
“I like to see nature, I like to listen to nature. Everybody has their own places that they find solitude and peace. This is mine. When you take that away you can’t put it back again.
“I say to those in authority, you may own this land on paper, but it is only for your lifetime and you should leave it as you found it. You don’t have the right to destroy it for future generations.”
Evelyn reflects: “I will effectively be driven from my home if this development goes ahead and our house will be made worthless. It is a fact that many people living near an area of industrial wind turbines can expect to develop wind turbine syndrome – a host of neurological symptoms and whole body physiological responses.”
David Thomson says he is sympathetic to the concerns of people like Donnie and Evelyn, particularly in regard to the health issue. But he believes that the human health impact assessment, being conducted by the Insitute of Occupational Medicine as part of the planning process, will allay fears of any negative effects on human health.
“It is a very understandable concern,” Mr Thomson says. “This is a huge project and the scale of potential impact, ranging from the economic and social to the environmental to the human, is a genuine thing. There are always going to be positive and negative impacts. We believe the positives will outweigh the negatives.”
He insists that the giant turbine blades will be turning at too slow a rate (12 revolutions per minute at their fastest) to cause any flicker effect. The rotation, he says, has the potential to be a nuisance, but not to affect human health. “The speed and frequency will never be fast enough to cause medical harm.”
Mr Thomson also states that the location of the turbines will be far enough away from houses to prevent a shadow effect being created.
“It is important that we have a debate around this project based on the evidence and we will be publishing the human health impact assessment along with a range of other studies in time.”
Mr Thomson states that there will also be a health issue for construction workers with such a huge civil engineering project. If it gets to construction stage, it will be important to use proper techniques to ensure the safety of workers and prevent deaths.