Large-Scale Heat Pumps to be Part of Germany’s Future

August 2022

The humble heat pump’s monster big brother is going to play a major role in industrial processes and district heating in Europe’s largest economy. Amidst continuing uncertainty surrounding fossil fuel energy supplies and the growing need to decarbonize industry, large-scale heat pumps, powered by renewable electricity, are increasingly being employed to deliver ecological and efficient solutions.

Experts say industrial applications abound.

“Your common-or-garden residential heat pump, which maybe delivers at peak 10 kilowatts of heat to warm your house to a balmy 21 Celsius, has a much bigger industrial sibling,” explains Germany Trade & Invest (GTAI) energy efficiency expert Rob Compton. “It can deliver multiple megawatts of heat at up to 150 degrees Celsius which means it can replace fossil fuels in many industrial processes.”

BASF and MAN have signed an agreement to build the world’s largest heat pump at the former’s chemical park in Ludwigshafen in western Germany. The 120 megawatt system will further heat industrial waste heat to generate 150 tons of process steam per hour, saving 400,000 tons of CO2. The steam will be fed into the chemical park’s steam network to power multiple industrial processes.

Although heat pumps cannot generate the more extreme temperatures needed to, for example, make steel or glass, companies still see plenty of industrial potential.

“High temperature heat pumps can be used in principle wherever process heat of less than 150 degrees Celsius is required. That’s often the case in the food, paper and chemical industries where low-temperature steam is used, for example, to sterilize food or in distillation processes,” says Compton.

A replacement form of process heat

 “In 2018, around 20 percent of the final energy demand in Germany was for process heat, much of it at temperatures below 150°C,” writes the Fraunhofer Institute for Solar Energy Systems (ISE). “For the most part, process heat is generated by burning fossil fuels. In order to reduce greenhouse gas emissions in the coming years, a switch to electricity-based heat generation is necessary. Heat pumps are able to provide heat at the required temperatures efficiently and provide stable process heat, even in large capacity classes.”

Projects of this sort are already underway from one end of Germany to the other. In addition to the BASF/MAN initiative, they include:

  • Europe’s largest heat storage tank 45 meters tall and with a capacity of 56 million liters, it will store district heating water in Berlin at a temperature of 98 degrees Celsius. It could utilize heat-pump technology.
  • A 33 MW system of three large-scale heat pumps at a power station in the Bavarian town of Rosenheim near Munich
  • A EUR 16.5 million, 23 MW district heating facility connected to a residual waste incineration plant that will be the largest in Germany and will cover seven percent of district heating consumption in Stuttgart.
  • A 20 MW river water source heat pump (RWSHP) in Mannheim.
  • An 8 MW high-temperature district heating facility on Potsdamer Platz in the middle of downtown Berlin, which will run on solar and wind.

Various state assistance programs are available for large-scale heat pump projects.

The need for networks

Another major application for large-scale heat pumps will be supplying heat to district heat networks. Heat pumps can take waste heat from everything from data centers to even sewers, bring it up to a “useful” temperature and deliver it to households.

This will be necessary because many fossil-powered power stations currently provide heat to district heat networks – aprocess known as “cogeneration.” If those power stations are taken offline, that heat needs to be replaced.

“The scaling up of large-scale heat pumps has to start quickly, explained Norman Gerhardt, group director of the energy economy and system analysis department at Fraunhofer IEE on the institute’s website. “Our climate goals require that they take over some 22 to 24 percent of district heating by 2030.

The German government has been given the green light to put EUR three billion into decarbonizing heating networks in the country.

GTAI sees a clear growth opportunity here for international manufacturers of large-scale heat pumps – both in industrial settings but also district heat.

Design for the BASF/MAN heat pump in Ludwigshafen © BASF/MAN