Scotland faces a massive hole in its energy supply, equivalent to the output of three power stations, by 2025 if it relies solely on renewables, nuclear operator British Energy (BE) will claim this week.

Scotland could move from a net exporter of energy to a net importer and may have to rely on nuclear generated power from England to plug the gap.

The Scottish government, which is opposed to any new nuclear power stations, dismissed BE’s claims as “nonsense” and re-affirmed its opposition to new nuclear power stations.

“Scotland does not want or need costly new nuclear power stations and is already well on its way to becoming the clean, green renewable energy capital of Europe,” a government spokesman said.

The issue could come to a head at an energy conference hosted by the Scottish Council for Development and Industry this week attended by industry experts and Jim Mather, the enterprise minister.

British Energy’s company secretary, Robert Armour, will say that Scotland will need at least three new large, affordable low-carbon conventional power stations to cope with a frequent 4GW gap in supply by 2025 — the equivalent of the output of three power stations

All of Scotland’s existing conventional and nuclear power stations are due to have closed by then.

“We are not saying the power needs to come solely from nuclear, but the policy should allow the competitive market to choose which low-carbon, affordable conventional plants are built. All options should be available,” a BE spokeswoman said.

The power, from the national grid, may include output from nuclear stations in England.

Gordon Brown reiterated the UK government’s support for new nuclear power in a speech in Glasgow last week.

A spokesman for the Scottish government said: “Harnessing the green potential can meet our future energy demands many times over, while also tackling climate change, and avoiding both the radioactive waste and enormous decommissioning costs.

“These claims — by a company that generates nuclear power — are clearly nonsense.”

Lesley Sawyers, chief executive of the Scottish Council for Development and Industry, said: “Business and the unions share concerns about the Scottish government’s no-nuclear policy, and the implications this could have for cost, security of supply and jobs in Scotland.

Meanwhile, French utility giant EDF was this weekend close to securing the shareholder support it needs to seal a £12 billion takeover of BE, Britain’s only nuclear power generator.

The French group has improved the terms of a bid that was rejected at the end of July by two large shareholders.

EDF offered 765p for each BE share, valuing the company at about £12 billion.

It is understood EDF is now considering a small increase in the cash price.

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