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Innovative compact HYbrid electrical/thermal storage systems for low energy BUILDings

Periodic Reporting for period 3 - HYBUILD (Innovative compact HYbrid electrical/thermal storage systems for low energy BUILDings)

Reporting period: 2020-10-01 to 2022-03-31

To address some challenges related to the integration of renewable energy in buildings, HYBUILD developed two innovative hybrid storage concepts: one for the Mediterranean climate primarily meant for cooling energy provision and one for the Continental climate primarily meant for heating and domestic hot water production. The project features four key components: (1) a compact sorption storage, based on a newly patented way to integrate an innovative adsorbent material within an efficient high surface heat exchanger; (2) a high density latent storage, based on a high performance aluminium micro-channel heat exchanger with additional phase-change material (PCM) layers, and an efficient electric storage; (3) the balancing of thermal and electrical energy flows through seamless integration of the compressor inverter in a DC-coupled system; and (4) by efficient conversion and upgrading of electric surplus and renewable thermal energy sources by compression and adsorption heat pumps. The system was designed in a compact way to easily allow for installation in existing and new buildings. These components will then be managed by an advanced control and building energy management system (BEMS) that can optimize the interactions between the components and the electrical and heat networks.

Therefore, HYBUILD seeks to increase the seasonal performance of the heating and cooling systems, increase the thermal energy storage density and achieve superior building and energy system flexibility via an easy to integrate and compact solution for new or existing buildings. The system objectives were to achieve energy and CO2 emissions reductions between 20% to 40% and a payback period of 8 to 15 years depending on the building configuration. The feasibility of the proposed solutions as well as the CO2 emissions reductions and payback time of the system were assessed at three demonstration sites located in Spain, Austria, and Cyprus.

Works required at the demonstrations sites for the installation and commissioning of the HYBUILD systems were carried out during the last period of the project. All targeted techno-economic, environmental, and social evaluations were carried out, but only limited demonstration data could be obtained.
Integration of these innovative components with the HYBUILD system as a wholewas done in the second half of the project. Definitions of the operating modes and the high-level optimization that manage both the thermal and electric sub-systems wisere developed. This includes definition and first use case testing of a reinforcement learning (RL) algorithm capable of managing the Mediterranean system.

For the three demo sites, pre-intervention monitoring started earlier in the project and the data was used later. In addition, definitions of the KPIs, scenarios and critical parameters to be assessed in the post-intervention analysis were made and included in the project deliverables.

In the second half of the project the main activities were focused on the installation of the three demos sites and its commissioning.
In Langewang demo the installation and commissioning occurred during late 2020. Fine tuning of the installation was carried out during the first semester of 2021, leading to a fully operative demo by summer 2021. In March 2022, after analysing monitored data, it was discovered that the system was not working as expected. In particular, the management of the RPW-HEX discharge was not the one foreseen and the RPW-HEX was basically never fully discharged. Then the control logic was revised.

In Almatret demo site, the installation of the main components was finished in July 2021. The full system commissioning couldn´t take place due several issues detected on some system components such as the Fresnel collectors and the electric subsystem. Finally, after the mentioned issues were solved, a failure in the motors of the Fresnel solar collectors was detected, which prevented the correct movement of the mirrors that concentrate solar radiation on the collector’s receiver. Therefore, the three motors were replaced and the system at the Almatret demo site is currently ready for the testing campaign.
In Aglantzia demo site the installation of the HYBUILD system was carried out during summer 2021, and the commissioning of the system was finalized by the third week of March 2022 as several issues occurred during the process. The approval for an exception for the HYBUILD system to connect to the grid was only approved by the Electricity Authority of Cyprus in mid-November. After that, a problem with the RPW-HEX was found out. Due to the lack of time to repair it, the consortium decided to by-pass the RPW-HEX and commission the system without it.

During the third reporting period the 19 deliverables remaining were submitted.In para llel to these activities, the dissemination, communication and exploitation plans of the project were delivered. Their implementation was carried out in a very satisfactory way during all the project, achieving KPIs in number of publications, events, and communication activities higher than expected.
Claimed Impacts of the Project:
-Overall reduction in energy demands of 30% for an optimized and configured system
-Estimated reduction of primary energy by 44% and CO2 emissions by 37% annually due to greater integration of renewable and heat pump operation.
-Increased share of renewable integration and potential for self-consumption and flexibility provision
-Return on investment of 8 years for non-district heating connected buildings, and 15 years for others.
-Extended solution life time for the PCM (at least 20 years)

Expected Results of the HYBUILD Project:
-Integrated hybrid storage and heatpump systems that optimize thermal and electricity flows, maximize use of free renewable energy, provide flexibility services to more efficiently meet either cooling demands or heating and DHW demands.
-DC bus controller solution ideal for interconnection with PV systems
-DC powered inverter for an air/water heat pump enabling optimal integration in the internal DC distribution network
-Innovative adsorber system with highly cost-effective porous aluminium heat exchangers
-Reduced space requirements of 500% compared to sensible storage
-Increased heat transfer in heat exchanges
-Significant peak load reduction in HVAC systems
-CSH collectors that maintain constant temperature at low radiation
-Innovative solutions for smart BEMS systems, combining optimization techniques for thermal and electric systems
-New design methodology for smart BEMS
-Consulting offer for designers, engineers, planners
-Adapted stainless-steel water storage
Official Logo of the HYBUILD Project