A group of Britain’s leading renewable energy firms have written to the Energy Secretary to express concerns about the planned Electricity Market Reforms.

Scottish and Southern Electric (SSE), Ecotricity, Good Energy, Renewable Energy Systems, Natural Power and Fred Olsen Renewables have written to Ed Davey warning that EMR proposals will only benefit nuclear generators and dissuade long-term investment in British renewables.

Speaking to the Guardian, Keith MacLean, Head of Policy at SSE, explained: “These proposals are too complex – they are unworkable, and they are looking more and more like a train wreck. This will expose consumers even more to price volatility. It's taking the risk of volatility away from the generators, who are best equipped to deal with it, and passing it on to consumers.”

“The only logic we can see in this is that they [ministers] are still trying desperately to hide the nuclear support. They seem to be prepared to make life more difficult for renewables in a last-ditch effort to keep the nuclear option open,” continued MacLean.

At the centre of the controversy are the planned Feed-in Tariff with Contracts for Difference (FiT CfD). The newly-proposed contracts are designed to provide low-carbon generators a guaranteed long-term price for energy generated. However, with pertinent details of the FiT CfD contracts suspiciously absent and the inevitably complex nature of such arrangements, the coalition of renewable companies believes that financial backers will find it hard to accurately judge returns and therefore invest elsewhere.

Dale Vince, founder of Ecotricity, told the Guardian: “Contracts for difference, which are essentially a subsidy for new nuclear, could put small suppliers out of business and kill the independent market. This risk does not exist under the current Renewables Obligation.”

Paul Steedman, of Friends of the Earth, also expressed concerns over the proposed FiT CfDs: “Contracts for difference are bad news for renewable energy. We're moving from one highly complex system – the renewable obligation – to something even more fiendishly complex.”

Commentating on the forthcoming Energy Bill, a Department of Energy and Climate Change spokeswoman said: “This is crucial legislation. The Energy Bill will reform the electricity market to keep the lights on and emissions down in a more cost-effective way, while reaping the economic benefits. It is designed to provide investors with long-term certainty and incentives to invest in low-carbon.”