London Array won’t go ahead with the expansion of the Thames Estuary off-shore wind farm, which is currently the largest in the world, due to possible effects on birds.
The decision to cancel the second phase of the development partly due to the requirements related to environmental assessment of the venture will undermine the UK’s position of the world’s wind energy leader.
The consortium behind the Thames Estuary development said there were "technical challenges and environmental uncertainties" surrounding the site.
Assessing the effect of the wind farm on populations of birds, especially the red-throated divers, would take at least three years, it was suggested.
London Array has formally asked the Crown Estate to terminate the lease agreement for phase two and has cancelled the remaining grid capacity it originally reserved at a National Grid substation in Graveney, Kent.
The project was supposed to deliver between 200 and 240 megawatts (MW) of power, in addition to the 630MW already being generated by the first phase.
London Array’s General manager Mike O'Hare said the second phase had always been subject to a planning condition requiring the company to ‘demonstrate that any change caused by the additional turbines to the habitat of the red-throated divers that over-winter in this part of the Thames Estuary would not compromise its status as a designated environmental special protection area’.
He said: "We believe it will take until at least January 2017 for that data to be collected and although initial findings from the existing phase one site look positive, there is no guarantee at the end of three years that we will be able to satisfy the authorities that any impact on the birds would be acceptable.
"In the absence of any certainty that phase two would be able to go ahead, our shareholders have decided to surrender the Crown Estate agreement for lease on the site, terminate the grid connection option, and concentrate on other development projects in their individual portfolios. Our existing operations at Ramsgate and staffing levels are unaffected."
The Department for Energy and Climate Change (DECC) said the rationalisation of off-shore wind projects in general is reasonable and a natural thing to happen as the industry gets mature.
"It reflects the fact that sites are often reduced or not developed given the particular circumstances of those sites, whether they are a very long way in the future in terms of the pipeline, whether they face particular geological or other issues,” said a DECC official
Offshore schemes with the potential to produce 41 gigawatts of power by 2030 were in the pipeline, although many of those were in the early "scoping" phase and firms would focus on the "best value projects".