How can farmers operate biogas facilities more economically? Only about 40 per cent of the burnt gas is transformed into electricity, while most of the energy produces waste heat. But in rural areas there is often a lack of people to use it. An idea developed by researchers at Justus Liebig University in Giessen could provide help. The scientists are testing how waste heat can be used to boost the growth of biogas facilities. The “green gold” is used as a raw material in cosmetics, pharmaceuticals, and chemicals, and can be further processed into biodiesel. In addition, the algae store carbon dioxide, thus improving the facilities’ carbon footprint.