The Helsinki district heating and cooling system, operated by Helen, integrates heating, cooling and CHP into one efficient energy ecosystem. The Katri Vala plant uses heat pumps to recover energy from sources that would otherwise be wasted. More than 80% of Helsinki’s district cooling energy comes from unused energy sources. In 2014, the system recovered 90,000 MWh of renewable district heat, including over 40,000 MWh from solar energy. The model demonstrates how integrated district heating and cooling can maximize energy efficiency and reduce waste.

The Kirchweidach project uses deep geothermal energy to supply renewable heat and electricity while supporting sustainable vegetable production. A 12-hectare greenhouse uses geothermal heat to grow regional peppers and tomatoes with zero CO₂ emissions. The project also supplies the local district heating network and aims to connect 300 additional households. A large thermal storage system and backup boilers ensure reliable heat supply. The project strengthens the local economy while demonstrating efficient geothermal energy use.

The Hungerkamp project in Braunschweig, led by BS|ENERGY, replaced old oil- and coal-fired heating systems with a local heating network. The system combines a biogas CHP unit, wood-chip boiler, natural gas backup boiler and hot water storage. The 4 km network supplies heat to 32 customers with a maximum demand of 8 MWth. It produces 100% green electricity and 98% green heat, saving around 8,000 tonnes of CO₂ annually. The combination of fuels and thermal storage provides flexibility and improves energy efficiency.

The Lodi district heating system has been modernized to improve both efficiency and sustainability. The project included recovering heat from a biomass CHP plant, optimizing substations and installing a thermal storage system. These measures significantly improved the system’s efficiency, sustainability and reliability. The recovered biomass heat is integrated into the district heating network to reduce energy waste. The network is now being expanded to serve additional areas of Lodi.