Energy companies are having to shelve projects that would help Britain to meet its 2020 renewables target because they cannot connect them to the national grid.

With waits of several years, and in one case almost a decade, before connections can be built, several wind farm projects might have to be put in abeyance.

Delays for land-based turbines caused by grid connection dates are a longstanding grievance of the on-shore wind industry and now threaten to affect the off-shore sector.

To avoid a repeat of the delays on land the national grid has called for the off-shore sector to be split into regions to allow for a strategic approach.

Under the present system a tender to connect off-shore wind farms is put out for each project, which executives at National Grid plc believe puts costs up and discourages potential investors.

Dividing the off-shore developments into regions would allow for strategic planning that could consider which part of the seas to concentrate on rather than skip back and forth between individual projects hundreds of miles apart.

“There is a lack of joined-up thinking, particularly in the current economic climate,” Stewart Larque, of National Grid, said. “Having transmission regions would allow better economies of scale, which is good in the current climate for raising financing. It is generally a much better way to ensure we are best placed to meet the country’s renewables targets.”

Attempts are also under way to introduce a strategic approach on land after pressure from renewable energy companies frustrated at costly delays. Talks between National Grid, renewables companies, the Government and the regulator have identified several wind farm projects that could have their grid connection dates brought forward. Among them is a scheme by Renewable Energy Systems to build 21 wind turbines at Drummuire, Caithness, which has been given a grid connection date of 2016 despite having been given planning permission in 2005.

Richard Ford, grid connections manager for RES, is awaiting a final decision but said it appeared that some progress was being made. Nevertheless, another project that the company is planning in Scotland has been given a connection date of 2018 and it is thought likely that it will slip back to at least 2020.

Mr Ford said: “If we really believe there is no prospect of better, whether or not we get planning approaval, we have to question whether it is appropriate to put it through planning.”

National Grid is responsible for organising grid connections and for deciding when they can be put in. Delays inherent in the planning system have been among the biggest problems, with the connections being subject to the same rules as the projects, often attracting intense local opposition.

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