Berlin’s high temperature heat pump ready to roll

GERMANY: A high-temperature heat pump using low GWP refrigerant R1234ze is set to begin full-time operation at the district heating, power and cooling centre in Berlin’s Potsdamer Platz.

The Qwark³ (Quartiers-Wärme-Kraft-Kälte-Kopplung or coupling of district heating, power and cooling) project, is expected to go into continuous operation in November, producing around 55GWh of heat a year. 

It is the result of a project involving Siemens Energy AG and German energy provider Vattenfall Wärme Berlin AG, with funding by Germany’s Federal Ministry of Economics and Climate Protection.

Around 30,000 households will be supplied with hot water in summer and 3,000 households with heat in winter. “In total, the system saves around 6,500 tons of CO2 in the city’s heating system,” said Vattenfall CEO Tanja Wielgoß. “That corresponds to 3.2 million m³ of natural gas.”

For Christian Bruch, CEO of Siemens Energy, the pilot project is an important milestone: “High-performance, high-temperature heat pumps will play an important role in the energy transition and the decarbonization of urban heating. Together with Vattenfall, we are testing such a solution here in Berlin for the first time under real conditions.”

In the future, the high-temperature heat pump will be part of Germany’s largest district cooling network.

For 25 years, the cooling centre at Potsdamer Platz has been supplying around 12,000 offices, 1,000 apartments and cultural facilities such as the Philharmonie or the Kulturforum with locally generated cooling. 

Currently, the cooling network supplies the connected buildings with cold water at a temperature of 6ºC all year round. It returns to the cooling centre at up to approximately 12ºC. 

The new high-temperature heat pump, which the Cooling Post believes is employing the low GWP HFO refrigerant R1234ze, will use this waste heat from the cooling water and raise its temperature to 120ºC. 

“This also saves 120,000m³ of cooling water,” Bruch explained. “We are supplying one of the world’s first heat pumps for the refrigeration centre that can generate such high temperatures in the 8MW power range. For this purpose, a new, environmentally-friendly refrigerant is used in the heat pump.”

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Berlin’s Potsdamer Platz to trial high-temperature heat pump – 26 March 2021
GERMANY: Siemens Energy and German energy provider Vattenfall Wärme Berlin AG have signed an agreement to demonstrate and trial a new large-scale, high-temperature heat pump in Berlin. Read more…