Pilot tests of a thermal energy storage system for the built environment

Aanleiding

For the energy transition in the built environment, it is needed to lower the demand for energy and to effectively use renewable energy in order to realise net-zero energy buildings.

Due to the fluctuation in renewable energy supply and fluctuating energy prices, energy storage, both thermal and electric, is essential. The focus on bridging the seasons (seasonal storage) has changed to the desire to be able to match the fluctuating supply and demand for sustainable heat and cold over the course of hours and days.

For energy storage from hours to several days, a compact, loss-free storage system offers great perspective, if realised at an attractive performance price ratio and is easy to integrate in existing and new installations.

Thermochemical energy storage is seen as an important solution with great potential. In the recent period, technology projects, amongst others in The Netherlands, have been carried out to overcome the hurdles for the application of ThermoChemical materials (TCM).

Points solved were:

• Stability
• Processability and optimization properties of a TCM
• Tailor-made industrial and scalable production process
• Long lifespan
• Reduction of the total system costs

Doelstelling

This project is focusing on pilot testing under Hardware-in-the-Loop and real environment conditions, the development of the first set-up of an initial production line, and technical and economic assessment for different applications in the market.

Thus, the goals of the SorpTES project are:

1. To develop system integration concepts and the system controller based on hardware-in-the-loop tests at the Laboratory of University of Innsbruck.
2. To demonstrate the well-functioning of the system through a number of pilot tests for different applications at different locations in The Netherlands and Austria.
3. To assess the technical and economic impact of the system for these different applications and boundary conditions.
4. To optimize the thermal energy storage system for applications and production.
5. To demonstrate a first industrial production process through assembly of systems parts (make or buy) and effective production of Na2S filled heat exchangers.

Korte omschrijving

To arrive at a commercially attractive SorpTES system, first of all, “handmade” systems will be produced and used in the first pilot tests.

Based on the results, the SorpTES system will be further optimized for industrial production and integration in different applications. Next, a production line based on make or buy and assembly will be set up.

An important aspect is the industrial production of the Na2S filled heat exchangers and the vacuum conditions for the system. At the initial production, eight complete systems will be produced for the second phase of pilot testing.

Important information from these tests will be implemented in the final design and production layout, in order to achieve a market-acceptable SorpTES system.

Resultaat

The project will result in a modular, easy to install and integrate SorpTES thermal energy system based on the thermochemical material Na2S.

The system arrives at TRL 8, with proven performance and market conform cost price. The application range is determined and installation guidelines including control set-points and integration layout are available.

Moreover, the ecological footprint of the system including safety and durability has been set up. A first industrial production process, make, buy, assemble, is fit for purpose.

With the successful completion of this project, the market entrance will accelerate towards high numbers of systems in the market, accelerating the energy transition, CO2 reduction, and effective implementation of renewable energy.