heat systems

Project PUSH-IT

Piloting Underground Storage of Heat In geoThermal reservoirs

PUSH-IT’s ambition is to overcome the seasonal mismatch between heat demand and heat generation from sustainable sources using underground heat storage. The EU-funded project focusses on three innovative technologies for high-temperature heat storage, as well as enabling technologies, societal engagement, and governance, policies and business models.

The goal is to develop this missing link in heat networks as a safe, reliable, affordable, and economically viable solution that fits existing and future regulatory frameworks. This contributes to reducing greenhouse gas emissions and achieving a net-zero carbon economy and society in Europe by 2050.

The pilots

PUSH-IT will demonstrate full-scale implementation of heat storage in geothermal reservoirs at three demo-sites: Delft (Netherlands), Darmstadt (Germany) and Bochum (Germany). Next to these key demo-sites, three ‘follower’ locations for future pilots are Berlin (Germany), Litomĕřice (Czechia) and United Downs (United Kingdom). At these sites, we will address specific local technical and societal challenges and engage local stakeholders. We will translate our findings into solutions that can be applied to heat storage systems across Europe.

5-10 MW
60 TJ/y
Delft (Netherlands)
Demo ATES (200-300m depth) site
storing heat from a geothermal doublet
(max 80°C) integrated into a heat network
used in the built environment.

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270 kW
20 TJ/y

Darmstadt (Germany)
Demo BTES site (750m depth) in
crystalline granodioritic reservoir
connected to a university campus,
to store excess heat (>50°C)
from a super-computer and summer
heat surplus.

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260 kW – 1MW
2 – 8 TJ/y

Bochum (Germany)
Demo MTES (120m depth) for
the reuse of summer surplus heat
from a university campus (max. 80°C),
supplementing the district heating

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50-70 TJ/y

Berlin (Germany)
Follower ATES site (400m depth)
to be integrated in a heating network,
using surplus heat from a wood-fired
power plant (max 90°C).

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2 MW
10-20 TJ/y

Litomĕřice (Czechia)
Follower BTES site (500m depth)
where several heat sources
(deep Geothermal, cooling of
photovoltaic panels) are integrated
into a field of deep boreholes and
will be integrated into the existing
heat network.

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United Downs (United Kingdom)
Follower MTES site (500m depth)
to be investigated within an abandoned mine
complex. The project is adjacent to a drilled
fractured geothermal reservoir with fluid
of ~180°C.

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The technologies

Explanation about ATES, BTES en MTES

Aquifer Thermal Energy Storage (ATES) is the storage and recovery of thermal energy in aquifers, which are permeable layers that contain groundwater.

Borehole Thermal Energy Storage (BTES) is a large, underground heat exchanger. A BTES system consists of a set of tubes installed in the underground, placed vertically in a borehole.

Mine Thermal Energy Storage (MTES) uses the mine water present in abandoned mines as a carrier for transporting heat.

The topics

Social engagement, societal benefits, and risk and regulations

will be addressed to ensure public understanding and support and speed up market upscaling of heat storage.

Optimal system integration & control 

will be developed to reduce costs, ensure environmental protection and achieve better integration of sustainable heat in the energy system.

Enabling technologies

and good practices will be employed to improve performance, safety and realisation of heat storage.


Development & Realisation

Crucial workover completed at Berlin’s ATES site​

Between April 15th and 17th 2024, new developments took place at the ATES site in Berlin Adlershof. Our team tackled some operational challenges within the research well and performed a workover. This intervention was necessary due to a previous issue related to a faulty cementing process during the installation of the well in 2022.

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Feel free to contact us

PUSH-IT is a project funded by the European Union’s Horizon Europe research and innovation programme under grant agreement No 101096566.
Funded by the European Union. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union. Neither the European Union nor the granting authority can be held responsible for them.

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