A legal row over solar panels on a house in a De Beauvoir conservation area could deal a big blow to the government’s pledge to cut energy use, the home’s owners warn.

Robert Cohen and Bronwen Manby, 47, have slashed energy bills from �1,300 a year to zero after a green makeover of their Culford Road home in 2009.

Energy use in the house – which featured in Channel 4’s Grand Designs magazine – has been cut by 80 per cent bythe use of super-tight insulation and solar power electricity.

The council was so impressed with the home’s design, it was nominated for the 2010 Hackney Design Awards – but was withdrawn when neighbours complained that the solar panels were ugly.

After a planning inspectorate meeting on Tuesday, the council is deciding whether the couple must remove the panels – as they installed a different design to the solar water heaters they had been given permission for when they realised that these could overheat if they ever went on holiday.

Energy consultant Robert and Bronwen believe their case is of national importance, given that the government’s pledge to cut carbon dioxide emissions by 80 per cent by 2015.

“Fundamentally, we all have to drastically reduce our energy consumption ... and conservation areas can’t be excluded from that,” said Bronwen.

“In so far as there is an impact to our neighbours, which we regret, that harm is much less than the benefit those panels are contributing to this house, de Beauvoir and the planet and pretty much every house in the richer world is going to have to follow suit.”

A council spokeswoman said planning permission should always be sought for any external alterations to conservation-area buildings.