Green technology development specialist ENER-G has this week stepped up its acquisition drive completing its third deal in the last six months with the acquisition of an 80 per cent stake in renewable heating and cooling firm Ground Source Solutions for an undisclosed sum.

The deal follows ENER-G's recent acquisitions of utility services firm CMR and smart metering outfit Switch2, and marks the latest extension to the company's portfolio of renewable energy and energy efficient technologies.

Nottinghamshire-based Ground Source Solutions provides coupled heat pump systems that harness solar energy absorbed by the earth to provide renewable energy for buildings’ heating, cooling and hot water requirements.

ENER-G managing director Derek Duffill said the deal would complement the company’s existing combined heat and power generators and help the company address the developing market for green heating solutions.

The move makes ENER-G the second firm in a week to attempt to break into the ground source heating market after energy giant Scottish and Southern Energy (SSE) announced it is to pay £15m for a 20 per cent stake in Geothermal International. Under the terms of the deal SSE will now offer Geothermal's ground source heat pump technology to its larger customers.