One of the most sustainable cities in Denmark
Høje-Taastrup has a population of more than 50.000 people and is located in Greater Copenhagen about 20 km west of the City Centre of Copenhagen. The municipality has committed itself to the requirements by the Danish society for Nature Conservation with a minimum of 2 % reduction of CO₂ emissions per year on a continuous basis. Over the last ten years, the municipality (geographically) has reduced its CO₂ emissions by more the 3 % each year.
The initiative to reduce its emissions comes partly from the former EU supported ECO-Life project under the Concerto initiative. From 2010 – 2015 the Danish partners carried out more than 67 successful demonstrations, improving energy efficiency and the integration of RES. This led to a Danish project called Høje-Taastrup Going Green, supported by the Danish Energy Authority, and laid the foundation for Høje-Taastrup’s participation in Cool DH. It is the only city that has received support to demonstrate the implementation of an accelerated transition to a fossil free future in a cost effective way.
In 2015, the district heating supply consisted of 51 % fossil free energy from biomasses, the renewable part of waste, solar, geothermal energy etcetera. Using a larger share of low-grade surplus heat and increasing system efficiency is an important step of reducing emissions even more.
Sources of heat production and temperature levels
The surplus heat will be retrieved from various sources:
- Cooling machines at the CITY2 Mall that will operate on power from more than 16,300 m² PV plant with an installed capacity of 2.07 MW (the largest roof mounted PV plant in the Nordic countries of Europe so far).
- Cooling machines and cooling of servers at the Danske Bank data center, DSB and hotels.
In the initial phase and as part of the COOL DH project, the collected heat will supply the district of Østerby, marked with orange close to CITY2 mall. The LTDH-network will serve an area of terraced houses with 158 dwellings. The LTDH network will eventually expand to neighboring areas with 350 houses (36,000 m²). New buildings are planned in the development area of Høje-Taastrup C and can be connected to the LTDH.
Close to the CITY2 mall, the Copenhagen markets are situated (marked with blue in the figure above). Their capacity of low-grade surplus heat sources is 8.7 MW, which is to be utilized via heat pumps to produce 11 MW cooling over time. It has a constant cooling demand with surplus heat and heat pumps that presently deliver 73oC /33oC (a mean temperature of 53oC). The capacity will expand with the implementation of LTDH and the operating temperatures will gradually be lowered to improve efficiency and fit the demand of the LTDH system.
The District Heating Company Høje Taastrup Fjernvarme is in charge of the implementation of LTDH. The utility was built in 1992 and approximately 6,800 buildings are connected to the grid that stretches 233 km. It is owned by the consumers as a cooperative.