Government may believe all UK homes could be powered by offshore wind farms but any investment should not be at the expense of other sources of renewable energy

The recent proposal by energy secretary John Hutton for the “third round” of offshore wind energy development has been presented as a massive boost for that form of renewable energy, offering the prospect that, by 2020, “enough electricity could be generated off our shores to power the equivalent of all the UK’s homes”.

It appears a beguiling and optimistic message, suggesting the government may yet meet its binding legal commitment under the Kyoto protocol of reducing greenhouse gas emissions by 12.5% below base level years by 2008-2012 and clearly expressed policy objectives of supplying 10% of UK electricity from renewable sources by 2010 and 20% by 2020. But is it realistic?

Wind turbine

Offshore wind has obvious attractions. Such projects do not ordinarily meet opposition from passionate local residents and other enthusiasts determined to preserve a cherished landscape, those concerned about a possible adverse impact on tourism or anxious about noise or organisations fearing harm to ecological or archaeological interests – to identify but some of the typical objections to onshore schemes.

However, it would be foolhardy to regard advances offshore wind energy as a reason to neglect other renewables such as onshore wind – a proven technology with obvious cost advantages – or offshore wave and tidal. Were it otherwise, the House of Lords Science and Technology Committee (Third Report – January 2006) would not have said that “offshore development is still largely a step into the unknown and potential investors face serious technological and commercial risks”.

So what have been – and will be – the key issues in relation to offshore wind?

  • Cost has been and will always be the major consideration: onshore wind has huge advantages both for construction and maintenance. But consumers may be prepared to accept that, if climate change to be addressed and renewable energy promoted by incentivising private industry, then, directly or indirectly, they will have to subsidise energy as they subsidise agriculture, transport, education and health.
  • Energy efficiency is another concern, related to grid connection and the fact that turbines at sea level may have to manage with less reliable winds than those on high ground onshore: but improving technology will assist to bridge that gap and the government is committed to addressing grid constraints.
  • Planning concerns may be concentrated on the siting of the onshore sub-stations and related infrastructure.
  • Fish(eries) may not be regarded as a very powerful constituency, even assuming that the fishing grounds are adversely affected.
  • Environmental impacts, on the other hand, will remain a major issue and are likely to be a fertile area of debate. The concern is not so much that a wind farm – built, ordinarily, in relatively shallow water - will affect the sea bed and life in and around the sea bed (though it may) but, rather, such projects have the potential adversely to affect the integrity of a number of marine habitats or bird populations designated under the Habitats and Birds Directives. This is, potentially, a major issue, as can be seen from the judgment of the European Court of Justice in the Waddenzee case and, more recently, the decisions of the High Court and the Court of Appeal in Merricks vs Sec of State (the Little Cheyne Court wind farm).
  • The next problem concerns potentially adverse impacts on navigation and radar, marine and air, civilian and military. This is an issue of technical complexity and of policy: but it cannot be assumed, simply because the turbines are offshore, and even if ships’ radar is not materially affected, that the MOD in particular will accept or accommodate any adverse impact on its own radar defence systems or tactical training areas, particularly as the most favoured areas for offshore wind development are likely to include the Greater Wash, Thames Estuary and North-West England. Indeed, how far Mr Hutton’s enthusiasm is shared by such other government departments remains to be seen.

The conclusion within the renewables industry should be that the government’s promise of support for offshore wind is to be welcomed – but only if the price is not a reduction in support for other technologies.