Most observers consider warmth pumps as small-scale heating techniques for homes, companies and condominium buildings. However XXL warmth pumps are already in service and doing the identical job for complete metropolis districts. Their apply, if profitable, shall be an necessary asset in decarbonizing societies and economies. Paul Hockenos experiences.
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The town of Esbjerg, Denmark, is out in entrance – however not for lengthy.
It boasts two industrial-size warmth pumps that present town of 100,000 with warmth from an unlimited useful resource proper off its coast, specifically the Wadden Sea. The purpose: to switch Esbjerg’s coal-fired energy plant, not less than partly, and finally in full.
The warmth pumps extract warmth from the seawater utilizing CO2 as a pure refrigerant to move the warmth and convey it to the next temperature degree. The seawater warmth pumps, manufactured by the German firm MAN, have a mixed heating capability of 70 MW, and since 2025 function in tandem with a 60-MW wood-chip boiler and a 40-MW electrical boiler plant. The blended applied sciences reduce funding and operational prices, and add to flexibility towards fluctuating gas and energy market circumstances.
They may provide home heating clients with roughly 280,000 MWh of carbon-free warmth yearly. No warmth pump has ever generated a lot warmth, however the Esbjerg pumps received’t stay prime of the pile for lengthy. In Cologne, MAN has one other underneath building that can have twice the capability.
There’s a consensus in Europe that warmth pumps are essential to decarbonizing warmth era. The system provider GEA group concludes: ‘Electrically pushed warmth pumps are in a position to change typical heating techniques based mostly on fossil fuels. They use both out there course of waste warmth or different warmth sources from the surroundings and switch the warmth to a excessive temperature degree. Even when utilizing pure coal energy, for instance, a warmth pump is way more sustainable than typical boilers because of its excellent effectivity, because it solely requires round a 3rd of the first vitality of a boiler to ship the identical output.’
The mega-scale techniques are distinctive and revolutionary in additional methods than one: additionally they function peak and backup load amenities. This functionality to function flexibly – it might probably ramp up from minimal load to most load, and from (sizzling) standby to full load, in lower than 30 seconds – makes them multipurpose techniques. They’ll readily stability {the electrical} grid by, for instance, supporting the combination of weather-dependent energy era like photo voltaic and wind, in keeping with MAN Vitality Options.
The Danish pilot venture ‘demonstrates that large-scale seawater warmth pumps using the non-toxic pure refrigerant CO2 are technically attainable and economically possible,’ in keeping with the IEA Know-how Collaboration Programme on Warmth Pumping Applied sciences.
As Denmark has intensive district heating networks, it believes that it’s going to generate half of its warmth by means of electrical energy by 2035. District heating ideas are additionally seen as a key measure for decarbonizing Germany’s heating sector, which the earlier authorities of Social Democrats, Greens and Liberals deliberate to facilitate by including 100,000 households a 12 months to district warmth networks. The brand new authorities, led by the Christian Democrats, agrees that Germany ought to have extra district heating however doesn’t particular a per 12 months determine.
Extra in Germany
Germany already has a number of massive warmth pumps, together with one not removed from my workplace in Berlin-Neukölln, although they don’t seem to be almost the scale of Esbjerg’s. In Neukölln, one of many 8.5-ton items is related to a number of large-scale boilers and 7 mixed warmth and energy (CHP) items are located on the heating plant website. The fuels used embody fossil fuel, wooden pellets, exhausting coal, biomethane and heating oil. Alongside a deliberate CHP-powered air-cooling system, additional potential warmth sources (river water warmth and geothermal vitality) will change into out there. The brand new know-how offers waste warmth a use and will increase the vitality effectivity of chilly era, in addition to offering inexperienced warmth from renewable electrical energy.
The warmth from the pumps in Berlin-Neukölln and adjoining Berlin-Kreuzberg reaches round 55,000 related households within the type of sizzling water. The water releases its warmth and flows again to the Neukölln plant by a circulation system. With roughly two to 4 kilometres of pipe being laid yearly, this district heating community now extends throughout a good portion of the Neukölln and Kreuzberg neighbourhoods.
The German suppose tank Agora Energiewende argues that the complete warmth demand in Germany as much as 200 levels can technically be lined by warmth pumps. ‘As a part of this, large-scale warmth pumps can exploit appreciable potentials provided by geothermal vitality, water our bodies and waste warmth,’ it argues in a report. ‘By 2045, large-scale warmth pumps may present 70 p.c of the district heating provide and thus change a really massive proportion of the fossil fuel used.’
Stuttgart and Mannheim
The biggest German warmth pump will quickly be in Stuttgart, constructed by EnBW, the place waste warmth from the cooling water drained from a CHP website will generate as much as 24 MW for district heating.
In Germany, along with Stuttgart, there are plans to put in massive warmth pumps in Berlin-Neukölln, Mannheim and Rosenheim, which shall be operative by spring 2026 – all supported by the Federal Ministry for Financial Affairs and Vitality. Getting in on the superlatives, Mannheim will boast the biggest river-based warmth pump within the nation, utilizing water from the Rhine River to warmth 3,500 households.
Agora Energiewende underscores that the roll-out of large-scale warmth pumps wants state help. The bigger venture of decarbonizing Germany’s heating ‘requires a triad consisting of strategic targets and incentives from the general public authorities, technological innovation on the a part of producers, and accelerated implementation by district heating suppliers and business.’
A climate-neutral warmth provide is essential for Germany to hit its local weather targets. With large warmth pumps on the prepared, it will appear that nothing on Agora Energiewende’s to-do listing is past Germany or the EU.
The views and opinions on this article don’t essentially replicate these of the Heinrich-Böll-Stiftung European Union.