The village Büsingen, located in the south of Germany, has a 100% renewable heating district. In winter the biomass boiler delivers most heat, while in summer the solar park takes over as main producer of heat. A rapeseed oil boiler is available for peak loads.
Brædstrup Fjernvarme has during the last 10 years been a Danish frontrunner in how to make district heating efficient, cheap for the customers and environmentally friendly at the same time through activities in the electricity market, smart metering, introduction of regularly service visits by the customers and support to improvement of house installations, implementation of the worlds first large scale solar district heating plant combined with natural gas fired CHP, implementation of borehole storage, heat pump and electric boiler to be able to maximise flexibility in the electricity market. The result has been a natural gas reduction of 38%.
The Hjallerup district heating network delivers heating to 1982 consumers in the towns of Hjallerup and Klokkerholm. Originally 2 CHP units produced all heat necessary. Nowadays, also a solar system, storage tank and biomass plant contribute to the delivery of more sustainable heat to the two towns.
In 2008, the Regional Municipality of Bornholm decided to become a 100% sustainable and CO2-neutral society in 2025, in which only sustainable and renewable energy is used. In 2019, already 60% of the island’s energy is produced fossil-free by using wind, sun and biomass power. The island’s green vision, big share of renewable energy, citizen and community involvement and replicability of the energy solution helped in winning the 2019 RESponsible Island Prize.
Metro trains generate excess heat when operating. The electric motors create heat due to their electrical and mechanical functioning at acceleration, at constant speed and at deceleration. About half of the heat in an underground system is produced when trains slow down: waste heat is produced by the brakes when a train approaches a station. The ventilation system of the trains also generates excess heat. For citys it is interesting to use this excess heat for their district heating network. In Berline the ReUseHeat project worked on an interesting example.
Waste water management systems exist in every city and could be exploited to heat buildings. They promise major heat recovery potential. The temperature of waste water ranges from 10 to 15°C on average, and can go even up to 20°C during summertime. This guarantees an adequate heat source for the operation of heat pumps throughout the whole year. The ReUseHeat project worked on an example of this application in the “Gran Arenas” project (Nice).
In 2010, data centres world-wide used about 350 TWh of electricity. It is just over 1% of the world’s total electricity use and it is constantly growing. Most of the power consumed by the Information Technology (IT) equipment is converted into waste heat, which must be removed to avoid damage to the equipment. The energy requirement of the cooling system represents up to 40% of the overall data centre energy consumption. The ReUseHeat project worked in Brunswick on the use of datacentre’s excess heat in the district heating network.
Southern European hospitals have high cooling and heating needs during the whole year. Combined district heating and cooling networks are, therefore, an interesting application. There are approximately 7,154 hospitals in Europe. Every hospital has considerable cooling needs and the excess heat from the cooling system can be captured and used in heat networks. Considering a conservative potential waste heat recovery tertiary buildings, up to 10 TWh year of heat could be supplied from this low-carbon source. The ReUseHeat project worked on an interesting application in hospitals in Madrid.
Arcelor Mittal Ghent has a lot of residual heat, which is currently cooled down in order to discharge it in a canal or into the air. Local authorities and the company are investigating whether the residual heat could be used for a heat network towards Zelzate and Terneuzen. The Province of East Flanders acts as an energy broker that brings stakeholders together, to create support and to support actions towards realization.