Thermowatt is an established Hungarian engineering company acting in the fast-growing renewable energy sector utilizing raw (untreated) communal sewage waste water energy for heating and cooling of buildings in city environments. Its patented technology to filter sewage water out of sludge, pass the brown water through a set of heat exchangers and generate low-temperature heating water through commercially available heat pumps to ensure adequate heating and cooling of larger building complexes is recognized worldwide. The company was set up in 2007 and has installed its technology in 6 instances thus far.