With clients keener than ever to investigate renewable technology, small builders are increasingly being asked to provide authoritative advice on relatively untried technology. So what will really work in practice and what's just eco-bling? Charlotte Webster of Solarcentury talks to Will Anderson, self-builder and author of 'Diary of an Eco-Builder', about his experience building a 'zero carbon' home.

Velux has launched a solar hot water system, developed to deal with the growing demand for environmentally friendly energy solutions in UK homes.

The manufacturer, known for its roof windows, has now branched out into the energy market, offering homeowners a system designed to be easily integrated into a home. It says that energy produced by the system can provide up to 70% of a home's hot water requirements.

The British Board of Agrément has issued its first-ever Certificate for a renewable energy technology - the Clearline range of roof integrated solar water heating panels from Viridian Solar (Certificate No 07/4474).

Clearline is roof integrated, meaning that it replaces tiles and sits lower in the roof. The resulting aesthetic is a great improvement on the standard installation of solar panels above the tiles. In common with other quality solar panels, Clearline has passed tests to the European standard for solar panels (EN 12975- 2 : 2006).