Leading regeneration specialist Roger Madelin has called for tougher laws to govern the use of renewable energy in large schemes.

The chief executive of developer Argent told delegates at last week's British Council of Offices conference in Dublin that the government needed to introduce nationwide legislation to create equal conditions across the UK.

He said the London Plan set a requirement for new buildings in the capital to take 10% of their energy from renewable sources. However, some planning departments in the country were accepting lower ratings, and others were demanding that up to 20% of energy be generated from renewable sources such as wind, solar or biomass.

Madelin, whose firm is behind the £2bn King's Cross Central scheme in London as well as Brindleyplace in Birmingham and Piccadilly Place in Manchester, said: "It's a very heavy-handed approach, but you've got to create a level playing field."

However, he added that King's Cross could only have gone ahead thanks to London mayor Ken Livingstone's "pragmatic" view of the 10% target for the largest London developments.

He said: "You'd have to have 523 wind turbines to hit 10% at King's Cross Central … It's impossible to hit 10% at King's Cross Central now. But if you make energy savings and are very keen you get your tick in the box."

The development, which will provide around 65,000 m2 of mixed-use space on 67 acres of brownfield land, includes 14 wind turbines on its periphery. Up to 20% of the roofs will also be designed either as gardens for residents or as spaces to attract wildlife.

The scheme got the go-ahead from Camden council in March, and is expected to go on site next year with Carillion, Kier and HBG the main contractors on the project's £400m first phase.

Madelin was talking at a session chaired by British Property Federation chief executive Liz Peace entitled "regeneration and legacy: force for good, or flash in the pan?" Other speakers included Pooran Desai, founder of developer Bioregional; Gary Lawrence, global urban strategies leader for Arup USA; Neil Pennell, engineering director of Land Securities; and Mark Wenlock, project director at Stanhope.