Neal Reid, from the renewable energy development team at ScottishPower in Glasgow, presented the perspective of an established and responsible energy company.
The government has placed an obligation on power companies to generate 10% of their electricity from renewable sources by 2010. For ScottishPower this means 1000MW. Scottish Power is currently the second-largest UK wind power operator, with 11 sites with an installed capacity of 128MW - nearly one quarter of the UK's installed capacity - and it has seven projects totalling around 500MW at the advanced planning stage. Locally, it is developing plans for Green Knowes, between Glen Devon and Coul Glen.
Global warning been linked to the burning of fossil fuels building up "greenhouse gases". The UK government has set a target of 10% of electricity generation from renewable sources by 2010 while the Scottish government has expressed an aspiration for 40% of generation to be from renewables by 2020. Nuclear generation is the other option that avoids greenhouse gases, but it is out of favour and not competitive.
There is a large, inexhaustible resource of wind in Scotland. Wind power is a proven and reliable technology which can be deployed quickly and produces no emissions in use. In the short and medium term there is no viable alternative to meet the government's targets. It is cost-effective: a cost of 2.5-4.0p/kilowatt-hour for onshore wind compares with five to six pence per kWh for offshore wind, seven pence per kWh for wave and tidal power (estimated since there are no current commercial technologies) and 10-15p/kWh for solar. It is a secure resource, not relying upon international trade, and increases the diversity of generating sources.
The Green Knowes windfarm can be taken as an example of what is involved. Good siting is crucial. A good site needs wind, access to the electricity grid and capacity in the grid, access to the site for construction traffic - each turbine blade is taken up as a single piece and doesn't bend! - no landscape or ecological designations or major ornithological concerns, and no problems with low-flying aircraft, or with radar or telecommunications.
Green Knowes has a good wind resource with scope for up to 45 wind turbines with a total output up to around 50MW. [By the time of writing, in early 2004, this proposal had been reduced to 35 turbines.] Each turbine would have a hub height of 60m (that is, the height of the tower) and a blade diameter of 70m. It is close to road and grid infrastructure and makes use of agricultural land. This would provide power, on average, for up to approximately 30,000 homes. It would cost around £40-45 million, funded by Scottish Power, and would take around 18 months to construct. It would have an operating life of 25 years following which it could be dismantled or renewed.
Before planning permission would be granted there would have to be a formal environmental assessment. This would include: landscape and visual impact, transport and traffic, noise, recreation and access, hydrology, birds, ecology (habitat and mammals), archaeology, aviation and telecommunications. There would also be early and wide-ranging consultation - the Green Knowes plans have already been modified following discussion with Perth and Kinross Council - including community consultation and public exhibitions.
It is available when the wind blows at the right strength, not when demand for electricity might be high. The electricity grid has been designed to take power from a few central power stations and distribute it out to users; wind power creates a more dispersed pattern of generation and there is a poor match between wind resource and grid capacity. It is considered unlikely that more than 15% of the UK's electricity could come from wind power. Public acceptance is also an issue.
In summary, a site such as Green Knowes offers a good wind resource on a good site in environmental terms. It has local and wider benefits, contributing to ScottishPower, Scottish and UK climate-change reduction targets.