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Hybrid storage for efficient processes (HyStEPs)

Das Projekt HyStEPs - Hybrid storage for efficient processes ist Teil der Energie-Vorzeigeregion NEFI zur Dekarbonisierung der Industrie. Darin wird an effizienten thermischen Speichertechnologien für Industrieprozesse geforscht.

Die Motivation für neue innovative Lösungen sind einerseits die Steigerung des Anteils erneuerbarer Energieträger im Stromnetz und andererseits die fortschreitende Dekarbonisierung. Beide Faktoren erfordern zukünftig eine drastische Kapazitätserhöhung der thermischen Energiespeicher in bestehenden Industrieanlagen bzw. Industrieprozessen.

Ruths-Dampfspeicher werden aufgerüstet

Objectives of HyStEPs

The objectives of HyStEPs are to increase storage capacity while reducing investment costs. The project team develops innovative hybrid storage concepts and tests them experimentally in order to increase the storage capacity of operating Ruths steam storage units by up to 40 percent in the medium term. Ruths steam accumulators are a widely used and proven storage technology and are used in a wide range of industries such as the food industry, luxury food industry, paper industry and metal industry. The necessary investment costs for a retrofit to a hybrid storage system should be only half of an equivalent Ruths steam storage system.

Research approach

In the project, several Ruths steam accumulator laboratory samples will be coated with innovative latent heat accumulators. Furthermore, heat conduction structures will be developed and implemented and a state of charge measurement for the hybrid accumulator will be developed to enable an optimal interaction of the two thermal accumulator types over the entire charging and discharging cycle. This innovative solution approach, which is based on patent applications of the AIT Austrian Institute of Technology, is intended to provide a preferably unchanged charging and discharging behaviour of the steam storage unit with increased storage capacity. In addition, a detailed demand analysis as well as a techno-economic evaluation based on three to five industrial processes from different industries will be carried out.

Results and findings

The concept is intended to enable an efficient and cost-effective increase in the storage capacity of steam storage systems. Reduced amortization times make it possible to realize additional thermal storage capacities.

Project start:

September 2018

Project duration:

24 months

Project partners

AIT Austrian Institute of Technology GmbH (Management)
Voestalpine Steel Donawitz
Edtmayer System Technology GmbH
TU Vienna

Funding:  Energy flagship region - New Energy for Industry (NEFI)
HyStEPs contributes to the NEFI innovation fields of energy efficiency and new processes, renewable energies, storage and load control by developing a new and innovative thermal energy storage concept.

Project website: www.nefi.at


R. Hofmann, S. Dusek, S. Gruber, G. Drexler-Schmid: "Design Optimization of a Hybrid Steam-PCM Thermal Energy Storage for Industrial Applications"; ENERGIES, 12 (2019), 898; 25 S. https://doi.org/10.3390/en12050898