Mijnwater Heerlen
Last modified by the author on 07/05/2020 - 09:41
- Year of commitment : 2019
- Address 1 - street : HEERLEN, Netherlands
- CO2 Impact : Currently, we reduce CO2 emissions per unit of energy by about 65%, mostly by reducing the collective energy demand. We plan to improve this to 80%, and finally to 100% by making use of sustainable electricity.
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35 000 000 €
- Builder
Mijnwater BV - Manager / Dealer
Mijnwater BV
Mijnwater Heerlend won a mention at the Dutch level for the Sustainable Infrastructure Grand Prize of the 2019 Green Solutions Awards + the international Sustainable Infrastructure Grand Prize.
The municipality of Heerlen did a pilot study with the purpose of repurposing abandondoned coal mines under the town as a geothermal source for heating and cooling. This was built in 2008, and it become the start of a heating grid. In 2013 the company Mijnwater BV was set up with the goal to build it out as a full size heating and cooling grid for the town of Heerlen. It was found that the mine water system has insufficient heat capacity for it to be used merely as source of heat, and that the usage needs to be optimised more towards storage of heat and cold. This was combined with a District Heating and Cooling grid design that is now being described as '5th Generation District Heating and Cooling' (5GDHC).
In this design, the temperature of water flowing in the grid is like in a (very) low temperature 4th Generation District Heating and Cooling system, but the grid is optimised to exchange energy between the customers, directly on the grid, but also via a storage system, between different points in time, and even between winter and summer. This is enabled by having a distributed system of heat pumps near the points of delivery, that guarantee that customers get the temperatures they demand. Booster heat pumps at the customer produce domestic hot water.
The result is a district heating and cooling grid that in the case of Mijnwater can function with only the underground mine water system that is still also heat source, but is ever more becoming mainly a heat storage. Currently, about half of all the energy for heating and cooling comes from the customers themselves: those that demand cooling power provide heat to the system, and vice versa. In the summer, the demand for cooling large offices produces a large surpluss of heat that is stored for use in the winter.
There are many small grids with the 5GDHC design, but the expansive size of the underground mine is at the scale of 10 km, which means that the backbone on the surface that was designed to exchange heat and cold with it also has that scale. It was reasonable to design the Mijnwater 5GDHC grid directly at that same scale, so it could serve a large fraction of the whole town of Heerlen. And because Mijnwater kept close to the low exergy principles the result is now probably the purest and largest example of a 5GDHC grid, and the leader in this field.
Mijnwater is in a process of constant optimisation of the pumps, the injection/extraction wells, and the clusters, which is planned to lower our electricity bill by about 16%. Improvement can be seen when comparing the years 2016/17 with 2017/18, and this will be done by 2021.
The latest new infrastructure was finished in january 2019, when we extended the grid of Cluster D out to a multipurpose community building, and on the other side back to a newly installed "Energy Transfer Station" that connects via heat exchangers to the mine water backbone. This gives us flexibility and options to both serve cooling power to an industrial area, and heat to the neighbourhood and a swimming pool behind the industrial area.
During 2019, the big leap forward will be to deliver Mijnwater services in the town of Brunssum. Initially, this will not be done by building a connection to our mine water backbone in Heerlen. We will start a new island grid, based on new underground thermal storage with boreholes in the aquifer, and employing a new pit-solution, EcoVat.
You can find more information in this video :
https://www.youtube.com/watch?v=6y6oJc91Cu4
Data Reliability
Self-declared
Funding Type
Public
Website Enterprise / Infrastructure
https://mijnwater.comSustainable Development
Governance
Mijnwater BV
Publicly Owned Development Corporation
Mijnwater BV
Other
Mijnwater BV
Public
The town of Heerlen started the company 'Mijnwater BV' to design, build, deploy, maintain, operate the district heating and cooling grid, based on the geothermal source and storage of the water in the abandoned coal mine. Ownership of the company has been taken over by the 'Limburg Energy Fund' of the province, and regional cooperation of 7 municipalities of 'Parkstad Limburg' has endorsed this grid as its main strategic solution for transforming the built environment.
Sustainable Solutions
- Governance :
- Quality of life :
- Economic development :
- Resources :
- Energy/climate :
- Business development
- Circular economy
- Infrastructure
- Climate adaptation
- Renewable energies
- Low-carbon materials/ infrastructure
- SmartGrids
5th Generation District Heating and Cooling System
The town of Heerlen developed an innovative piece of infrastructure to turn the abandoned coal mines under the town that are filled with water into a large geothermal resource, and a storage volume for heat and cold. Subsequently, this large resource was the basis for building a large town-sized 5th Generation District Heating and Cooling Grid. On such a grid, the customers are connected with each other, so that customers that need cooling power will give away their excess heat, that can be used by others who need heating. Averaged over a year, the demand for cooling and heating power is very balanced: we deliver 20 TJ/year of both. Having the large thermal storage volume allows us to keep the surplus warmth from the summer, to keep our buildings warm in the winter. But also to use the wintercold to help deliver cooling in the summer. This network makes use of a system of heat pumps that are positioned near the end users, to make sure that the right temperature can be delivered. The result is a system that does not need to burn any fuels, but does depend on electricity. Because energy is shared, the electricity demand is small enough that we can already reduce CO2 emissions by about 65%. In the longer run, we will be able to become more efficient, and also use sustainable electricity, allowing us an open path towards total decarbonization.
A process of constant optimisation of the pumps, the injection/extraction wells, and the clusters is planned to lower our electricity bill by about 16%. Improvement can be seen when comparing the years 2016/17 with 2017/18, and this will be done by 2021.
The latest building of new infrastructure was finished in january 2019, when we extended the grid of Cluster D out to a multipurpose community building, and on the other side back to a newly installed the Energy Transfer Station that exchanges energy with the mine water backbone. This gives us flexibility and options to both serve cooling power to industry, and heat to the neighbourhood behind this building.
During 2019, the big leap forward will be to deliver Mijnwater services in the town of Brunssum. Initially, this will not be done by building a connection to our mine water backbone in Heerlen. We will start a new island grid, based on new underground thermal storage with boreholes in the aquifer, and employing a new pit-solution, EcoVat.
Photo credit
Mijnwater / Bak Hoensbroek, Pascal Moors,