The heat pumps are mostly for district heating projects and use ammonia, according to Lars Reinholdt from the Danish Technology Institute (DTI).
Speaking at the Chillventa Congress (on 15 October 2018), Lars Ove Reinholdt, product manager, refrigeration and heat pump technology at the Danish Technology Institute (DTI) based in Aarhus, said Denmark boasts 41 large natural refrigerant-based heat pumps, mostly with ammonia and mostly for district heating projects.
The heat pump capacities range from 0.2 to 10 MW. Subsidies granted by the Danish government to encourage district heating plants to install large heat pumps have played a crucial role in their proliferation, Reinholdt said.
Subsidies driving uptake
In January 2018, Denmark’s Energy Agency approved funding for 13 large heat pump projects for 11 small district heating networks in Denmark.
The heat pump projects will likely use ammonia as the refrigerant due to Denmark’s strict f-gas legislation. The Scandinavian country began to phase down HFCs in 2001, five years earlier than the EU as a whole (see Accelerate Europe Issue 7 to learn more).
“To our knowledge, all of the heat pumps are based on ammonia as the refrigerant due to HFC regulations in Denmark, which only allow the use of a maximum 10 kg HFC per unit,” Thomas Capral Henriksen – chief consultant at Dansk Energi (the Danish Energy Association), which represents energy companies in Denmark (including producers and distributors of electricity and large producers of district heating) – told Accelerate Europe in December 2017.
Henriksen, whose organisation tracks the development of heat pumps, said that the previous round of subsidies – awarded in 2015 – went to natural refrigerant-based heat pumps.
The number of heat pump projects supported has increased compared to 2015, when the Danish government awarded a total of DKK 26.6 million (3.58 million euros) to 10 large-scale heat pump installations in small district heating plants.
Copenhagen aims for 300 MW heat pump
DTI’s Reinholdt, told the Chillventa Congress that Copenhagen had asked him to help install a 250-300 MW heat pump in the city’s district heating network. The district heating supplier had asked for one heat pump. “But it was not possible to find a heat source to heat that amount,” Reinholdt said.
“There is no sewage plant [or heat source] big enough,” he explained. “They are now thinking of installing multiple heat pumps for district heating, with ammonia, in several stages.”
A 5 MW heat pump, which will take waste heat from sewage water and use seawater from the bay of Copenhagen, will be installed in spring 2019.