The argument against on-site renewables should be treated with caution

The UK Green Building Council’s statement that on-site renewables cannot deliver the government’s definition of zero carbon on as many as four out of five new homes needs questioning carefully.

It seems that some of the people partially responsible for causing the problems in the first place are now trying to reduce the effectiveness of the legislation, possibly in an attempt to maintain the value of their extensive landbanks. The real issue is cost, not the technical challenge of delivering zero carbon.

Any environmental innovation increases cost in the short term, until sufficient economies of scale are reached. The Code for Sustainable Homes increases its specifications at two-to-three year planned intervals, allowing developers to build out their landbanks before the next level becomes mandatory. So there isn’t too much for them to complain about.

 The UKGBC’s recommendation that off-site generation be allowed puts even greater pressure on green grid renewable energy reserves, which in any case are required by existing homes and public services. Even if the entire practicable area of the UK’s continental shelf were covered in 2MW turbines, it would meet only 15 % of our present electric needs by 2050 – with tidal energy contributing another few per cent. So it doesn’t look as though there is any spare off-site harvesting opportunity for the UKGBC to adopt.

This is an edited excerpt. For the full column see