HYSTORE - Hybrid services from advanced thermal energy storage systems

The project HYSTORE (nr. 01096789) is a Horizon project where, KTH Royal Institute of technology is developing one of four thermal energy storage (TES) solutions within the project: PCM HEATING solution. This is a pilot-scale TES using phase change materials (PCMs), designed, constructed and techno-economically optimized in combination with a heat pump in KTH-Live-in-Lab . This is a close collaboration of the Department of Energy Technology ( EGI ) and KTH-Live-in-Lab (KTH-LiL) at Industrial Engineering and Management (ITM) School with Constructional Engineering and Design ( BYV ) at the School of Architecture and the Built Environment (ABE). BYV-ABE is the project technical leader and project leader for KTH.

Background

Global heating and cooling (i.e., thermal) demands take more than 50% of the final energy use today, and is largely powered by fossil fuels [1]. Thermal energy storage (TES) is thus an inevitable component for decarbonizing energy systems today. TES can, via peak shaving and load shifting strategies improve efficiencies, recover waste thermal sources, allow financial benefits. TES can also accommodate an increased deployment of intermittent renewables as both heat but also as electricity, by combined operation with heat pumps, chillers and like, enabling flexible sector coupling (FSC). Different TES technologies and systems have been already implemented in energy systems, however, mostly resolving to sensible TES and simple phase change material (PCM) solutions like ice. The compact TES types like latent TES (via PCMs) and thermochemical heat storage are also gaining momentum for a wide variety of heating and cooling applications. However, their exploitation at large is still limited due to factors such as: their relative complexity; lack of data at real application scales; lack of standard engineering guidelines for their installation and operation; and lack of knowledge on the potential of TES in FSC (providing grid services, among others).

In this context, the Horizon project HYSTORE aims to address these challenges and thereby to contribute in elevating the technology readiness level (TRL) of compact TES technologies. Within the 18 partners, four technical TES solutions (coupled with heat pumps) for specific climate conditions are being designed, constructed and operated in chosen demo-sites, and then optimized for synergies with the building energy management system and therein with the district/regional energy systems. The four solutions are:

1. All- ALL-IN-ONE PCM solution

2. LOW-TEMPERATURE PCM HEATING&COOLING solution

3. PCM HEATING solution

4. TCM HEATING & COOLING solution.

Aim and objectives

Aim at KTH:

Design, construction & operational and control optimization of a “Combined System of LHTES and a Heat Pump (HYSTORE PCM Heating Solution)”

Objectives at KTH (Figure 1):

Optimal material selection (for minimal supercooling & hysteresis analyzed in a bench-scale Latent heat thermal energy storage (LHTES)system, considering different PCMs (including bio-based alternatives)
Optimal LHTES + Heat exchanger (HEX) component analysis, design & construction, followed by the integration with a suitable Heat Pump (HP), for pilot-scale
Optimized control and operational strategies of the combined LHTES + HP system (i.e., the PCM Heating Solution) to cater to a real space heating application in KTH Live-in-Lab, Testbed KTH as the demo site
Optimized building (energy) system management and control with the PCM Heating solution’s real operation in KTH Live-in-Lab
Optimal techno-economic performance analysis for heating application (with peak shaving, load shifting & flexible sector coupling) at Nordic climate conditions.

Project summary

HYSTORE at KTH covers all the three TES design phases: material, component and system, and combined operation of TES and heat pumps for real heating applications. The results are expected to bring contributions in Swedish as well as European contexts, to elevate the state-of-the art of latent heat thermal energy storage (LHTES) technology as well as its combined operation with heat pumps. In HYSTORE, the technical tasks are led by Dr. Qian Wang at BYV, while the tasks at EGI are led by Dr. Saman Nimali Gunasekara, and at KTH LIL by Dr. Jonas Anund Vogel, joining forces with Assoc. Prof. Justin Ningwei Chiu, Assoc. Prof. Samer Sawalha (EGI), Dr. Marco Molinari and Dr. Davide Rolando (EGI & LIL).

The project tasks for EGI include: phase change material characterization in bench-scale; numerical design and optimization of pilot-scale LHTES (and heat exchanger) configurations; the construction and commissioning of the optimal LHTES; its installation in-combination with heat pumps in KTH-Live-in-Lab; and then the control and techno-economic optimization of this LHTES-heat pump solution together with both BYV and KTH LIL.

The project will evaluate a number of TES- heat exchanger configurations numerically, whereby an optimal configuration (starting from an existing configuration shown in e.g. Figure 2) will be chosen for real pilot-scale installation. To choose optimal phase change material candidates for this system, material testing at bench-scale (using and developing from the rig shown in Figure 3) is being performed at EGI. Combining these numerical and experimental results, a final optimal TES- heat exchanger (HEX) configuration using the identified optimal PCM candidate will be designed, commissioned and installed at LIL, integrated with a heat pump. This solution is what is referred to as the HYSTORE PCM Heating solution, specifically catering to Nordic climate conditions. The HYSTORE PCM Heating solution will be operated for covering space heating demands of the Testbed KTH at LIL, and will be optimized for appropriate operational and control strategies for peak shaving and load shifting. The interactions and synergies this HYSTORE PCM Heating solution has with the building energy management system will be therein mapped by BYV and EGI. These results will then be projected to similar building modules and benchmarked against similar building energy system models obtained via other heating/cooling solutions tested by BYV, collaborating with other HYSTORE partners, during the last phases of the project. These benchmarked models on synergizing the thermal and electrical systems in buildings are expected to enable robust peak shaving and load shifting strategies. This will also lead to an increased penetration of renewables into building energy mixes, by means of using such TES and Heat pump combination solutions.

Figure 2. The existing PCM-TES configuration from which the HYSTORE PCM Heating solution will evolve for more optimal storage and heat exchange functions

Figure 3. The bench-scale PCM-TES system at EGI that will be used for material testing in HYSTORE pr Figure 3. The bench-scale PCM-TES system at EGI that will be used for material testing in HYSTORE project

Funding

Project funding is provided by the European Commission.

Timeframe

2023-03-01 till 2027-12-31

Researchers

Contact person and Project Leader at EGI and the School of Industrial Engineering and Management (ITM)

Saman Nimali Gunasekara assistant professor saman.gunasekara@energy.kth.se , +4687907430 Profile

Contact person and Project Leader at KTH and School of Architecture and the Built Environment (ABE).

Qian Wang researcher qian.wang@byv.kth.se , +4687908696 Profile

Project Leader at Live-in-Lab

Jonas Anund Vogel co-director javogel@kth.se , +4687907446 Profile

Project members

Justin Chiu associate professor justin.chiu@energy.kth.se Profile Samer Sawalha associate professor samer@energy.kth.se , +4687907889 Profile Aditya Suswal adityass@kth.se Profile

Publications

Coming soon