SPF Institut für SolartechnikProjektleiterin SPF
+41 58 257 41 69mihaela.dudita@ost.ch
In this applied Research Project the SPF Institute for Solar Technology carried out a feasibility study for the storage of solar energy in an aluminum redox cycle. Alumina (aluminum oxide) can be converted to elementary aluminum with an electrolysis smelter process that consumes electricity from solar or other renewable sources, and this elementary aluminum can then be transported to the point of use where it is used for the production of heat and electricity in buildings or industrial processes.
We combine solar energy with innovative water treatment technologies to enable communities or institutions to purify water on-site. This includes the design of suitable PV systems in conjunction with water treatment methods such as Gravity Driven Membranes (GDM) or solar water disinfection (SoWaDis).
There is a lack of knowledge on the lifetime assessment of modern solar selective absorbers. In the project ColourAge, the performance and durability of different aluminium based coatings are studied. The combined effect of high humidity, condensation and temperature on the degradation of optical and chemical properties is assessed. Advanced techniques for materials characterization were used to identify the main degradation mechanisms: surface/interface (XPS, TEM) and chemical (EDX) analysis, as well as optical measurements (UV-Vis-NIR and FTIR spectroscopy).
Clean water, a reliable power supply and cooling systems for medicines and vaccines are not a given in many rural hospitals in Africa. To ensure better healthcare also in remote regions, the EU is supporting SophiA project, which relies on modular containers to produce drinking water, heat, cold and electricity using solar energy. SPF Institute for Solar Technology is part of the international team responsible for the solar technology, the Life Cycle Assessment of the SophiA systems as well as the energy management and control of the subsystems.
The storage of larger amounts of renewable energy over longer periods of time can be considered one of the last unsolved problems of the energy transition. In the HePostAl and HybridStock projects, it was shown that aluminium enables the seasonal storage of renewable energy by means of a redox cycle and that the annual demand for electricity and heat of a double detached house can be covered with approx. one cubic metre of aluminium. In principle, both primary aluminium from aluminium smelting and aluminium from recycled material streams can be used for the production of heat and electricity. In this project, the effects of the choice of material on energy use, the quality of the reaction products and their market value as well as the ecological life cycle assessment (LCA) are investigated.
The overall goal of the TRI-HP project is the development and demonstration of flexible energy-efficient and affordable trigeneration systems. The systems will be based on electrically driven natural refrigerant heat pumps coupled with renewable electricity generators (PV), using cold (ice slurry), heat and electricity storages to provide heating, cooling and electricity to multi-family residential buildings with a self-consumed renewable share of 80 %. The innovations proposed will reduce the system cost by at least 10 - 15 % compared to current heat pump technologies with equivalent energetic performances. Two natural refrigerants with very low global warming potential, propane and carbon dioxide, will be used as working fluids.
The project is lead by SPF and supported by the research programme H2020 of the European Union – grant agreement ID: 814888
Seasonal energy storage is one of the largest challenges of the energy turnaround. In the project HybridStock, the seasonal storage of renewable energy in aluminium is investigated. At times of high availability of electricity from renewable sources, this energy is converted to chemical energy and stored in elementary aluminium. In winter, chemical energy from the oxidation reaction of aluminium is used to produce heat and electricity.
In this project the concept which was the subject of the feasibility study HePoStAl is further pursued through laboratory work and the construction of prototypes.
A 1 kW closed sorption thermal energy storage system (TES) prototype is set-up and tested at HSR-SPF. This can be charged in summer with heat from solar thermal collectors or with electricity from photovoltaic modules. The system can achieve a significantly higher volumetric energy density compared to sensible hot water storage. The closed sorption system is designed to work with different sorbent-sorbate pairs (NaOH-H₂O, LiBr-H₂O and LiCl-H₂O). Scaling to larger units with correspondingly higher power will be done in the frame of SCCER HaE (Heat and Electricity).
