SCIENCE / Tilting at wind turbines: Wind power has been hailed as the ultimate green energy source. But there is still an environmental price to pay, says Malcolm Smith

AS AN eco-friendly builder, Chris Lord-Smith is no stranger to energy- saving innovation. Low-energy light bulbs, heat recovery units and argon- filled double glazing are part of his stock-in-trade. So when Ecogen, a company set up to develop and exploit wind power, proposed to build an array of wind turbines near his home in the hills around Llandinam in mid-Wales, he welcomed the prospect. What could be more environmentally benign, he thought, than using wind to produce power?

That was a few years ago. Now that he has experienced the 103 turbines in operation for more than a year, wind power is as abhorrent to Lord-Smith as houses without loft insulation. 'It's like being near a large air-conditioning unit,' he says. 'The noise comes from all directions, so you feel surrounded by it. It bounces off trees and hills. In some rooms you can hear it with the double-glazed windows shut. And if it suddenly gets windy in the night, the turbines start up and wake us.' Yet the closest turbine to Lord-Smith's house is 750 metres away.

Other residents affected by noise from the 30 metre-high turbines, both at Llandinam and at other turbine power stations in the Welsh hills, describe the sound as a constant throbbing, like living in a tumble drier. The noise is due partly to the whoosh of the turbine blades, partly to the sound of the gear mechanisms. For some people living close to these latter-day windmills, the peace and tranquillity of their pastoral landscape has been ruined.

Complaints about noise from wind farms are set to increase now that the Government has received more than 300 applications for building wind turbines with the help of public subsidies. Earlier this month, Tim Eggar, the Energy Minister, said that 30 at most would be successful.

Noise is relative, of course. The sound produced by wind turbines is way below the levels encountered in factories, say, where it can be a health hazard. But at 35-45 decibels (the Government's planning guidance figure for noise from a wind farm 350 metres away), it is twice as high as the background level of 19 decibels typical of a still night in the countryside. Legal regulations start to apply where noise levels are above 30 decibels.

For houses 600 metres or more from a turbine, noise as measured by conventional equipment is little above the natural background level. At the top of a hill, the noise generated by the turbines tends to be swamped by the sound of the wind itself. But many experts now realise that a funnelling effect down some valleys can produce a much more intrusive noise in the calm air of the valley bottom - such as the one in which Chris Lord-Smith lives. Developers, and local authorities who grant planning consent for turbines, are taking these concerns more seriously than they once did.

But noise isn't the only issue blowing in the wind. The visual impact of the growing number of wind farms on the hills, valleys and woodlands of the Welsh countryside is fuelling a highly polarised debate.

So far, throughout Wales 249 turbines at 10 different sites have planning consent. Of these, 181 are running and 46 are under construction. Llandinam's 103 turbines are the largest number at one location anywhere outside California. More than 40 anemometer sites - for measuring wind speed - have been given temporary planning permission; many of these may well be proposed as the site for more turbines.

Because of concern about the effect of wind turbines on the landscape, the Countryside Council for Wales (CCW) has commissioned Chris Blandford Associates, an environmental consultancy, to review the impact of three developments. Their conclusions will be published early next month.

What they have found is that smaller turbine farms can often be designed to fit better into the landscape than larger ones. They needn't stand out as eyesores. The large Llandinam development, while not visible from most villages nearby, can be seen more than nine miles away. This, the consultants say, diminishes the wild, remote quality of the area. For walkers in these windy hills, turbines can ruin what were once precious open vistas.

Yet many of the people who live and work in the shadow of the turbines find them quite acceptable. In the Blandford study for CCW, 70 per cent of people interviewed in villages close to wind farms said they would be happy to see more of them. A more traditional 'Not In My Back Yard' attitude - with far fewer people wanting them - was encountered in villages well away from any existing turbine developments.

Among the supportive comments were: 'put them anywhere - they are picturesque' and 'they look like daffodils - should be painted yellow]' At the opposite end of the spectrum were more predictable remarks such as 'visual pollution' and 'an eyesore ruining a beautiful area'. CCW's policy is to press for them to be built in less visually sensitive places. The nine 300-kilowatt turbines on an existing harbour wall at Blyth, north of Newcastle - cheek by jowl with cranes, masts and factories - may be a role model. This polarisation of views is reflected by the positions adopted by environmental pressure groups. The Campaign for the Protection of Rural Wales (CPRW) opposes all large- scale wind turbine farms. It wants a moratorium on any further developments, to provide a breathing space for a proper assessment of their impact. Friends of the Earth, on the other hand, is still very pro. 'We support sensitive development of all forms of renewable energy, including wind power,' says Fiona Weightman, FoE's energy campaigner.

She does acknowledge, however, that turbines can produce a significant noise and be visually unappealing. 'We don't want large wind farms in designated areas such as National Parks,' says Weightman, 'and we want to see developers take action to reduce noise. Moving individual turbines to a better position, cladding towers with improved sound insulation and reducing noise from their gearboxes could all help.'

Criticism of the effect of turbines on birds is also growing. The 269 turbines built around Tarifa, on the southern tip of Spain, are on a prime migration route for more than 300,000 birds of prey and storks crossing to Africa. According to Carlos Sunyer of the Spanish Ornithological Society at least 14 species - including honey buzzards, black kites, lesser kestrels and white storks - have been found cut to pieces by the rotating blades.

Erected with substantial European Union funding, up to 2,000 more turbines are planned. The developments, in a Special Protection Area for Birds (designated, ironically, under an EC directive), are raising fundamental questions at the Brussels- based commission after a formal complaint by the Spanish society.

In California, too, collisions have been reported, mainly involving red- tailed hawks, American kestrels and golden eagles. Again, most of the fatalities have been on migration routes. In Wales there are no reports of birds being killed or injured at any wind farms built so far. Conservationists are cautious, however, being all too aware of the vulnerability of slowly increasing populations of red kites and merlin.

Critics of wind energy point to what they see as the pathetically small amount of electricity generated. When they are turning, Llandinam's 103 turbines produce 300 kilowatts apiece. Their maximum output is 31 megawatts, 30 times less than an average (1,000 megawatt) coal- or gas-fired power station. Wind supplied more than 1,000 megawatts in EU countries last year, half of it in Denmark.

Yet the growth is slow. The Government's goal is to produce 1,500 megawatts of the nation's energy from renewables - wind, wave power, deep rock (or geothermal) energy and hydro-electric - by the year 2000. If a good proportion of this were generated by wind, thousands of turbines, at hundreds of wind farms, would be needed. Yet the Government directs only 2 per cent of electricity tax revenues towards renewables under the so-called Non Fossil Fuel Obligation (NFFO). The remaining 98 per cent goes to support nuclear power. The CCW argues that, if the NFFO favoured small turbine developments instead, the extra funds could be used to reduce their impact on the landscape.

Wind energy enthusiasts point to the savings in pollutant and greenhouse gases that would accrue if a specified amount of electricity were generated without using coal or oil. Simon Bilsborough, CCW's senior economist, questions this substitution argument. The wind doesn't always blow at peak morning and evening electricity consumption times, so conventional power plants have to be operated day and night anyway to make sure enough electricity is generated. Pollutant emissions therefore stay high.

Take sulphur dioxide, one of the main components of environmentally damaging acid rain. Bilsborough calculates that the 2,020 tonnes that the Welsh turbines currently operating 'save' represents just 0.06 per cent of the total pumped into Britain's atmosphere. He calculates that if the amount of subsidy paid to wind turbine development in Wales (about pounds 20m per year) were invested in energy conservation instead, more than three times the amount of electricity generated by these turbines would be saved.

While much could be achieved by simple jobs such as lagging pipes, insulating lofts properly and cutting draughts, conventional power station efficiency could be improved, too. Most operate at little more than a third of peak efficiency. All the more ironic, then, that Chris Lord-Smith's home is about as energy-conserving as a house can be.

As he lies awake at night, listening to the rumble of the turbines, that is little comfort.

Dr Malcolm Smith is the chief ecologist for The Countryside Council for Wales.

(Photograph omitted)