Permitted Development for domestic wind turbines mooted in Scotland

According to the BBC, homeowners in Scotland may soon be allowed to put wind turbines up to 3m high and 3.5m in diameter on their roofs without planning permission, under permitted development rules. Free-standing wind turbines as tall as 11m and at least 100m from neighbouring properties could also be allowed, except in conservation areas. Air-source heat pumps would also be allowed, even in conservation areas, if they were invisible from the road.

The proposals are due to be launched next Friday as part of an ongoing consultation on renewable energy.

Climate change minister Stewart Stevenson claims the proposals strike the right balance in the best interests of Scotland, claiming: "By cutting red tape in the planning system we can make it easier for households to generate their own clean, green energy." He argued that the proposals will boost Scotland's renewables sector, potentially generating new jobs.

There's still considerable controversy about the carbon efficiency of small scale wind turbines, with fears that they may not be able to save enough carbon during their operational life to repay the carbon debt incurred in their manufacture. And many urban sites will not have sufficient airflow to operate the turbines effectively. The plans do allow anemometer masts, which measure wind speed, on roofs and in gardens, for a maximum of 12 months, but it's possible that many homeowners will skip this step to reduce the expense.

Relaxing planning restrictions on renewables is generally a positive step, but much better information on the relative efficiency of different systems is essential to avoid people investing in sytems which, despite their good intentions, don't reduce carbon emissions.

New tidar power project for Scotland

Massive new tidal turbines could be operational at three undersea sites around Scotland by 2011, according to a report in The Times. ScottishPower Renewables has identified the Pentland Firth, the Sound of Islay, and the North Antrim coast off Northern Ireland as the most suitable sites for the underwater turbines. Each location will have between five and 20 1MW machines which could lead to a combined output of 60MW - enough to meet the energy needs of 40,000 homes.

Tidal turbines are described as similar to wind turbines but with much shorter blades which turn more slowly. They are anchored to the sea bed and aligned to the tidal flow. The UK has almost a 10 per cent share of the global tidal power resource, representing 13bn kilowatt-hours. More than 80 per cent of the potential is located in Scottish waters.