An Oxford company which is set to become the first renewable energy business quoted on the Stock Exchange has taken over one of its partner businesses.

Intersolar Group, based at Oxford Science Park, has taken over Cardiff firm PV Systems, which has installed solar heating systems in hundreds of homes and schools all over Britain.

Intersolar makes Electra-Slate, which is the size of a conventional building slate but can generate two watts of electricity using a pioneering technology known as thin-film photovoltaic cells.

The takeover gives Intersolar the ability to design systems with traditional solar cells as well as its new thin-film cells.

Intersolar aims to raise £18m by floating on the Alternative Investment Market, which it will use to build a new factory so that it can triple production.

Chairman Philip Wolfe said: "Home power is recognised as the fastest-growing sector of the photovoltaic market.

"The UK is now striving to catch up with other leading countries and needs stronger indigenous photovoltaic companies."