Denmark Leads The Way With The Largest Heat Pump In The World
The Good News -
Denmark aims to eliminate coal-fired plants by 2030. In 2023, Danish utility DIN Forsyning partnered with MAN Energy Solutions to change district heating and replace Ørsted's coal-fired plant in Esbjerg, Denmark. This project's 60MW heat pump system now provides heating for a staggering 100,000 people, replacing coal-fired thermal generation using Denmark's electricity, which is 2/3 from wind and solar.
Key Facts:
- Scope: Two heat pump units
- Task: Continuous district heat production
- Capacity: 60 MW
- Annual Supply: 280,000 MWh
- Population Served: 100,000 inhabitants
- Carbon emissions cut: 120,000 tonnes annually (equivalent to the emissions of 50,000-55,000 cars)
Project Background -
The Esbjerg heat pump project centres around two advanced heat pump units that utilise the innovative HOFIM® compressors with integrated turbines. These units are designed to operate 24/7, ensuring a continuous supply of district heating by transferring energy from seawater to heating water, powered by renewable energy from the grid.
Quotes Relating to the Project -
The key? Seawater -
"We're phasing out coal-fired heat and replacing it with carbon-neutral district heating produced from wind and seawater. The switch will save around 120,000 tonnes of CO2 emissions per year and support Denmark's effort to integrate electric renewables into the grid." - Kenneth Jørgensen, Project Director, DIN Forsyning.
From seawater to district heating: how the heat pump works -
"The plant is like a reverse air conditioner, but instead of cooling a building, we're using renewable electricity to extract heat from seawater and multiply it for the district heating network. It's a solution that supports decarbonisation efforts and can be used not only for district heating but also industrial processes worldwide." - Karl Böhle, Senior Project Manager, MAN Energy Solutions.
Technology Specifications - here’s what was put in place -
At the heart of this system is the use of CO2 as a refrigerant, capitalising on its high density and heat capacity. The CO2-based heat pump operates using a transcritical cycle, which allows it to generate heat efficiently under varying conditions.
Key Features:
- Refrigerant: CO2 (R744)
- Source Temperatures: 1-4°C in winter, 14-20°C in summer
- Thermal Capacity: Up to 60 MW for two units
- Sink Temperature: 60-90°C
- Seawater Intake: 4000 litres/second
Main benefits:
- Naturally occurring
- Available in large quantities
- Inexpensive compared to synthetic refrigerants
- Environmentally friendly
- Low global warming potential (GWP)
- Non-toxic, non-explosive
- High density
- High volumetric heating capacity
- Low thermodynamic critical point
The process loop uses MAN's oil-free, hermetically sealed HOFIM® compressor with an integrated turbine, a heat exchanger on the heat sink side, an evaporator on the heat source side, and the necessary circuit piping.
Supporting Renewable Energy
The system's design ensures minimal environmental impact, which is particularly important given Esbjerg's proximity to the Wadden Sea, a UNESCO World Heritage Site. Located near wind farms, the heat pump system can quickly adapt to power demand fluctuations, regulating up to 12 MW within 30 seconds. This capability supports both decarbonisation and grid stability.
A model for the future
The Esbjerg heat pump project sets a new standard for sustainable district heating. By harnessing renewable energy and innovative CO2-based technology, it not only meets Denmark's climate goals but also provides a model for future projects globally. This initiative demonstrates how cities can achieve climate neutrality while ensuring a reliable heat supply for residents.
For further information on this article, please visit: https://www.man-es.com/docs/default-source/document-sync/esbjerg-heat-pump-reference-case-eng.pdf?sfvrsn=45a29f76_5
