The way has been smoothed for a massive solar farm to cover half the former RAF Coltishall site.

Norfolk County Council bought the former air base for £4m in January last year and, as part of its vision for what might happen at the 600 acre site, a 50-acre solar farm was proposed.

But, the council says further investigation has established that, with the electric supply grid in Norfolk at capacity, the necessary 22km cable to connect the Coltishall site to Norwich would cost millions of pounds.

That makes a small scale farm unviable, according to council officers, so to recoup investment a much larger scheme would be needed.

And a renewable energy developer has approached the council seeking a 25-year lease on up to 300 acres (120 hectares) of grassland to run a large scale commercial solar farm.

At a size of about 170 football pitches, it would be the biggest in Norfolk and one of the largest in England.

Taking up half the site, tens of thousands of photo-voltaic panels would generate 60 megawatts of energy - enough to power more than 18,000 homes for a year.

The council says it cannot reveal the identity of that developer - or how much such a scheme would cost - for commercial reasons.

But they have drafted in specialist advisors from Deloitte to help officers carry out due diligence on the proposal.

The controlling Labour/Liberal Democrat cabinet at County Hall decided today to increase the scale of the solar farm originally envisaged in the council's development vision for the Coltishall site.

If and when a planning application comes forward, it will be discussed by North Norfolk District Council, rather than by the county council.

While the developer would make the money from the sale of power to the National Grid, the county council would receive the rent for the land.

Richard Bearman, leader of the Green group, said he welcomed the solar farm proposal, but that mistakes made in the past must be learned.

The recommendation was agreed subject to officers ensuring the council is not exposed to inappropriate financial risk.

Norfolk County Council officers said it would be clear if the deal could go ahead within months.

And George Nobbs, leader of Norfolk County Council said: 'I cannot say more for reasons of commercial confidentiality, but I do not think anybody will have grounds for complaint about the deal which officers are currently negotiating.'

Families living in nearby Badersfield, who are angry at proposals to rip up the ends of the runway, had previously signed a petition backing a solar farm.