We are pleased to announce another strong performance in the first half of 2018. The equivalent of 66,500 homes have been powered by our invested portfolio of renewable electricity generation projects over the last 6 months, 25% more than in the first half of 2017. Operating profit1 was £2.9 million, up 5.7% compared to the same period last year.
We have made new investments this year in renewable heat and battery storage projects, both new areas for Thrive. Space heating and hot water accounts for 80% of UK residential energy consumption; we are investing in Rendesco which specialises in implementing ground source heat pump systems in new-build retirement homes. In May, we entered into a joint venture with battery storage developer Aura Power. Our joint investment model offers UK businesses the chance to use battery energy storage systems to cut electricity bills and reduce energy use at the most polluting periods of peak demand, contributing to a cleaner electricity grid.
Going forward we intend to invest further in renewable heat projects, continue to provide financial support to community energy projects via our Community Energy Funding Bridge and develop investment opportunities to demonstrate that subsidy free renewables can work.