Environmental activists claimed a major victory last night when plans for Britain’s first new coal-fired power station for 30 years were shelved after a sustained campaign.

The announcement by E.ON that it would delay a decision on Kingsnorth for three years is a serious setback for the Government’s principal environmental policy of supporting the capture and storage of carbon emissions from coal plants. The delay also heightens the risk of power cuts after 2015, when EU rules will force Britain to close nine of its largest and most polluting power stations.

E.ON’s decision was greeted as a victory by Greenpeace and will encourage activists to redouble their efforts to block other controversial schemes, including the planned third runway at Heathrow.

Kingsnorth, in Kent, was expected to be the first new plant to be fitted with carbon capture and storage (CCS) technology, with one quarter of its output due to have the technology installed. It became a focal point for environmental activists and the existing plant, due to close in 2015, has been targeted several times. Six Greenpeace protesters who climbed the chimney were acquitted last year after the jury accepted that the plant posed a greater threat to the planet than did the actions of the activists.

Activists boarded a barge and prevented coal being unloaded in June. Last month naked protesters occupied the offices of Edelman, E.ON’s public relations agency.

E.ON denied that the delay was linked to the protests and blamed it on the fall in demand for electricity in the recession. The price of gas, with which coal competes for electricity generation, has also fallen sharply. The German company said in a statement: “We can confirm that we expect to defer an investment decision on the Kingsnorth proposals for up to two to three years. This is based on the global recession, which has pushed back the need for new plant in the UK to around 2016 because of the reduction in demand for electricity.”

An E.ON spokeswoman admitted that the delay meant the existing plant at Kingsnorth would stop generating electricity before a new one alongside it could open. She said: “The recession will buy everyone a lot of time to iron out details. The plant was going to open around 2012-13 but we are not going to make a decision on whether to open it for two to three years and it would then take around four years to build.” She said that the future of CCS, which is extremely expensive and has yet to be shown to work commercially anywhere in the world, partly depended on the price of permits to emit carbon. The price is currently very low but could rise if a global deal on cutting emissions is agreed at a UN conference on climate change in Copenhagen in December.

John Sauven, the Greenpeace director, said: “This development is extremely good news for the climate and in a stroke significantly reduces the chances of an unabated Kingsnorth plant ever being built. The case for new coal is crumbling, with even E.ON now accepting it’s not currently economic to build new plants. The huge diverse coalition of people who have campaigned against Kingsnorth because of the threat it posed to the climate should take heart that emissions from new coal are now less likely.

“Ed Miliband now has a golden opportunity to rule out all emissions from new coal as a sign of Britain’s leadership before the key Copenhagen climate meeting.”

Responding to the news on Kingsnorth, Shadow Energy and Climate Change Secretary, Greg Clark said: “This latest news underlines the chaos in Labour's energy policy. At a time when the Government is predicting power cuts by 2017 its plans for new capacity with carbon capture and storage are disintegrating.

“A Conservative government will immediately authorise at least three power stations fitted with carbon capture and storage, enough to keep the lights on by 2017 and giving Britain a leading role in vital new green technology.”

High-profile protests

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