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A selection of current SPF projects

A selection from our current projects illustrates our work in hand. Should any synergy between your business and ours appear, feel free to enquire within our organization.

Please note that for confidentiality reasons only public projects are displayed. Generally, projects that are carried out for private clients are subject to non-disclosure or confidentiality agreements.

Also see our previous projects.

DHWStrat - Thermal stratification of domestic hot water storage tanks

Thermal stratification of heat storage has a high impact on the efficiency of thermal energy systems. This correlation was shown in the StorEx project for combined storage tanks, with a new test procedure for stratification efficiency that is based on the second law of thermodynamics. This procedure is now well established, but could so far not be applied to domestic hot water (DHW) storage tanks. Therefore, in the DHWstrat project, the existing procedure was extended and applied to four DHW storage tanks. The results show that a well stratified DHW storage tank concept not only achieves higher comfort and better hygienic conditions, but in combination with a heat pump saves up to 40 % electrical energy compared to another storage tank. These results underline the need to evaluate the stratification efficiency also of DHW storage tanks.

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In «Slurry-Hp I» we have shown the potentials of cost reduction of using the ice slurry technology with the supercooling method for solar-ice applications. First work on supercoolers was done in «Slurry-Hp II» and it is currently being developed in the «H2020 TRI-HP». «Slurry Store» will work towards the development of an ice slurry storage concept for this application. Several options for charging (icing) and discharging (melting) the slurry storage will be experimentally evaluated and a design will be proposed. Last but not least, an ice releaser (cristallizer) to ensure a continuous ice slurry production will be implemented in the laboratory set-up for a capacity of 5 kW.

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OptimEase – Enegetic and economic Optimization of building clusters

Within the OptimEase project, a modelling framework is developed that allows for the energetic optimization of groups of buildings by using their synergies. By comparing the optimal solution of a group of buildings with the sum of optimal solutions for each individual building, the economic and environmental benefits of aggregating several buildings is evaluated.

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NewCline (H2020 - CSP ERANET)

Thermocline is a cost efficient thermal storage system able to reduce capital costs of CSP up to 40 %. The objective of this project is to develop new thermocline concepts that can be applicable to different CSP plants. Detailed simulation of two thermocline concepts will be validated with the experimental data generated in this project. Based on the simulation tools, both concepts will be evaluated and optimized in terms of system integration and LCOE savings on a CSP system level and up-scaling for CSP target applications.

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AlEnCycles – Use of primary and recycled aluminium to produce electricity and heat

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.

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DiffStrat – Stratification of Thermal Storage Tanks by Diffusor Design

Thermal storage systems are increasingly being used to balance the production and demand for heat or cold. In combination with renewable energy systems such as heat pumps or solar heat, the temperature stratification of the thermal storage is a decisive factor for the efficiency of the systems. But also in combination with biomass heating plants, the advantages of good thermal stratification are great, since stratification achieves more constant supply temperatures to the network and more storage capacity can be used with the same storage volume, thus reducing the cycling of the heat generators. Inflow geometries play a special role here, both for the loading and unloading of water reservoirs. In the projects DiffStrat and DiffStrat 2, different inflow geometries were investigated for their stratifying effect, both by measurements in the test bench and, building upon these results, also by CFD simulations.

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PLURAL – Plug-and-Use renovation of facades with adaptable lightweight systems

Reducing heat losses from existing residential buildings by refurbishing the building envelope is an important step to reduce the heating demand of buildings. In the EU project PLURAL, prefabricated façade modules are being developed and tested, which enable novel possibilities for energy generation, heat/cold supply and ventilation with the façade. The prefabrication of the façade modules is intended to enable rapid and cost-effective refurbishment in an inhabited state. Three field installations will be used to demonstrate renovations in different European climates. Simulations will be used to analyse components and buildings, and a Big Data management platform and decision-making tool for component selection and integration will be developed.

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No. 958218.

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SimplyDrain – Simplest solar drainback systems as add-on for DHW preparation in multifamily houses

A simple concept of a solar thermal drainback system is developed that can be used as add-on when refurbishing existing domestic hot water preparation in multi-family buildings. Three variants of the concept will be designed by means of energy simulation and calculation of levelized cost of heat. The most promising variant will be sized with thermohydraulic simulations and built in the lab. This demonstrator will be used to analyse and show safe operation conditions and the feasibility of the system concept.

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SolSimCC – Influence of climate change and user behaviour on solar energy systems

In SolSimCC, the effects of climate change and user behaviour on the profitability of solar energy systems (photovoltaics and solar thermal) were investigated. The results show only a minor influence of climate change on the profitability of solar plants. However, two changes significantly increase the profitability of solar thermal systems: firstly, the replacement of natural gas with more expensive biogas or syngas, and secondly, the adoption of more realistic heat consumption profiles instead of the idealised profiles often used in simulations today.

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SolInd2Service – Solar Heat for Swiss Service Sector

The service sector accounts for about 16 % of Switzerland's final energy consumption (GES 2017). More than half of the energy consumed in this sector is used to provide low-temperature heat (< 120 °C) for heating, hot water and process heat, which is mainly derived from fossil fuels. For this temperature range, solar heat is a suitable and proven technology, which has been known for a long time from the domestic sector. In the project SolInd2Service, the heat demand in different parts of the service sector is investigated and possibilities to integrate solar thermal systems will be identified.
Subsequently, best-case scenarios will be developed to demonstrate and facilitate methods for the implementation of solar thermal energy in the service sector.

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BillySolar – Reduction of CO₂ emissions through integration of scalable and cost-effective modular solar process heat units

BillySolar Logo

The aim of this project is the development of a fully configured and modular scalable solar thermal system for use in industry at various sites (production sites) and applications (heat sinks). For this purpose, a universally applicable smallest unit for heat supply is developed, which is adapted for the widest possible range of heat sinks. This unit consists primarily of a solar thermal heat generation system, and if applicable in combination with waste heat recovery and coupling to a district heating network. As an alternative to solar thermal, photovoltaics combined with heat pumps or possibly a combination of both approaches are investigated. Based on this, financing models are derived.

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SolTherm2050 – Opportunities through solar heat and thermal energy storage for the Swiss energy system 2050

Soltherm2050 answers the question of the potential of solar heat in combination with thermal energy storage in Switzerland, identifies the best possible application areas, assesses the opportunities and risks and finally develops a roadmap for promotion and to expand these technologies. The goal is to make the greatest possible contribution to the Energy Strategy 2050, with a focus on a realistic implementation process.

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SensOpt – Solar active buildings with 100 percent solar heat fraction

Source: Jenni Energietechnik AG

Fully solar heated single and multifamily houses are already technically feasible. The seasonal storage in these systems is associated with corresponding investment cost and demand for storage volume. This project analyses whether cost and used storage volume can be reduced with the combination of solar thermal with a PV driven heat pump system. Therefore, an existing system will be monitored and new innovative concepts are simulated and optimized. The project is carried out in collaboration with Lucerne University of Applied Sciences (HSLU) and Jenni Energietechnik AG.

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Related Special Report: «Using the Summer Heat in Winter» (PDF)

CCT-Bat – Home batteries system test

The CCT-Bat project is to develop a system test for home batteries, with which all relevant operating conditions can be tested within three days using the hardware in the loop principle, in order to determine the cycle efficiency and other key performance indicators. Different target functions of the systems (self-consumption, electricity tariffs, and grid benefits), as well as single and multi-family houses and different load profiles will be considered.

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ReProWP – Novel reversible air/water-heat pump system for an energy-efficient office building

Due to the increased need for comfort, new office buildings are often cooled nowadays. At the same time, the legal requirements for energy efficiency and the ecology of building systems have become stricter. In the ReProWP P&D-project this development is taken into account. A new type of reversible air/water-heat pump was developed, the heat pump is operated with the natural refrigerant propane. The office building which was investigated is Minergie-P certified and has a reversible heating and cooling distribution (change-over system). The final results are presented in the SFOE final report.

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LegioSafe – Legionella in hot water systems

SPF has carried out three projects from 2017 – 2020 on the topic of Legionella in hot water systems. In the LegioSafe project (2018), a literature study was conducted on legionella, temperatures in drinking water systems, and the occurrence of legionella in systems with solar thermal water heating. In 2019, a field study was conducted including 110 buildings in «LegioSafeCheck». More than 300 shower water samples and over 100 samples from the lower area of heat water tanks were taken and analysed for Legionella. One year later, in the project LegioSafePlus, exclusively buildings in which legionella > 1000 CFU/L were found in at least one shower water sample in 2019 were further monitored and re-sampled. The results were made available for the standardisation work of SIA 385/1:2020 and are described in three final reports. Results of both field studies were summarised in an article published in «hk gebäudetechik». Due to installation deficiencies identified in the field, a leaflet on the correct combination of hot water circulation and central cold water admixture was produced with the help of suissetec, GKS and Swissolar as well as EnergieSchweiz.

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VenTSol – Evaluation of user behaviour with regard to ventilation, shading and room temperature depending on the outdoor climate

In the VenTSol project, the behaviour of residents with regard to window ventilation, shading and room temperature will be investigated by detailed monitoring of five apartment buildings. This study should help to create detailed user profiles, which can be used for simulations and energy calculations. User behaviour is compared to the prevailing external climate, internal climate and energy consumption. The project should contribute to a better understanding of the so-called «UserGap».

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Hybrid BioVGE (H2020) – Hybrid Variable Geometry Ejector Cooling and Heating System for Buildings Driven by Solar and Biomass Heat

Within the EU project Hybrid-BioVGE an innovative system for heating and cooling is developed. The cooling device is based on a Variable Geometry Ejection (VGE) cooler. Driving energy is heat from solar collectors or from biomass. SPF is supporting the development of collectors that deliver heat at 75 – 90 °C, and is testing the heating and cooling system with the established Concise Cycle Test (CCT) method. This method is specifically adapted in order to be able to test also cooling systems.

The project is supported by the research programme H2020 of the European Union – grant agreement ID: 818012, acronym Hybrid-BioVGE

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KlimaGapLite – Literature study on different weather correction methods

In the SFOE project ImmoGap it was found that the choice of the method for weather correction of the energy monitoring data can have a strong influence on the determination of the performance gap. For this reason, a literature study on different weather correction methods was done for the SFOE and further research needs were identified. The literature study shows that the current situation regarding the weather correction of energy monitoring data is not satisfying.

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TRI-HP (H2020) – Trigeneration systems based on heat pumps with natural refrigerants and multiple renewable sources

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

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HybridStock – Energy Storage in Aluminium

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.

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Final report (PDF, English)

16 A-Buildings – Power grid stabilisation and influencing users through electrical power limitation for buildings

Limiting the electrical purchase and feed-in power of buildings to a low level is attractive for grid stability. Because of this limitation, the building's own solar power consumption would be optimised, the PV system output limited, peak demand reduced and, if necessary, an electric energy storage installed. Due to the different interests of the stakeholders, the advantages and disadvantages of the new technical concepts for the power limitation must be examined. The feasibility of such a concept will be investigated by means of simulations.

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Big-Ice – Assessment of solar-ice systems for multi-family buildings

The overall goal of the project is to assess and quantify the potentials of solar-ice systems for multi-family buildings with the possibility to include cooling demands. Special emphasis will be given in quantifying the energy performance using different hydraulic configurations and weather data sets on several Swiss locations. Hundreds of parametric transient dynamic simulations in TRNSYS will be used to quantify the system performance factor under different boundary conditions. The project also aims to develop fast algorithm tools for feasibility checks purposes using machine-learning algorithms trained with TRNSYS simulations.

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Slurry HP II – Super-cooling ice slurry heat pumps for solar heating applications

The idea behind this project is to use the supercooling ice slurry method for solar heating applications. This innovative concept could provide a breakthrough in solar and heat pump systems with ice storages by reducing the cost of the system by 10 %. The cost reduction would be achieved by eliminating the heat exchangers from the ice storage and storing ice in the form of slurry. The slurry HP II project aims to proof the concept of heat exchangers operated with supercooled water using ice repellent coatings.

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cpExakt – Measuring of heat capacity of liquid heat carriers

In this project a calorimeter was built for the measurement of the specific heat cp of heat transfer fluids with a measurement uncertainty of ±0.3 %.
The apparatus will be used for quality assurance at the SPF and is available for measuring fluids of third parties as well. This brings significant advantages for manufacturers and suppliers of heat transfer fluids that can deliver physical properties of their fluids with higher accuracy, for facility operators of large systems that can survey the energy balance of their systems with higher accuracy, and for researchers and developers that may determine more accurately the energy balance of prototype systems that use heat transfer media other than water.

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HePoStAl – Heat and Power Storage in Aluminum

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.

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OpEEr – Benefits of room temperature controllers

Studies on individual room control and the so-called self-regulating effect (ErrEnEff project) were extended from single-family houses to multi-family houses. Three different room temperature control variants were evaluated and compared in terms of final energy demand, living comfort and economic efficiency. For this purpose, a reference building that corresponds to an average Swiss apartment building, was designed in IDA ICE. Parallel to the room control, the differing heat demand of apartments at the top and on the ground floor compared to apartments in the middle was also investigated for the case that they have identical or differing room temperature set points.

OpEEr is supported by the Swiss Federal Office of Energy (SFOE).

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BigStrat – Stratification of Large Thermal Storage Tanks

A combination of measurements from seven field systems and simulations of systems with large thermal storage tanks was used in order to derive rules for the extrapolation of design rules that lead to good thermal stratification from small (800 l) sized tanks to large (up to 200 m³) tank sizes. In addition, a deflection relation was defined that allows for the prediction of the preservation of existing stratification depending on the distance to the next obstacle in the storage tank, when fluid is entering vertically or via an elbow pipe in the direction of the storage tank cover.

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ProsumerSkin – New solution for renovation of multifamily buildings

This pilot and demonstration project shows new ways for the cost-efficient renovation of multifamily houses to «nearly zero energy» buildings. The core components are multifunctional facade elements which, in addition to thermal insulation and windows with integrated comfort ventilation, contain both power generation with photovoltaics and the distribution of space heating. In a first phase of the project, the building physics fundamentals are analyzed and the feasibility is demonstrated with a prototype and simulations. In a second phase, a multifamily building in Bern will be renovated with this new concept.

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OblaTherm – PVT and foundation slab as a heat source and sink

For the new building of Oblamatik AG in Chur, a heating and cooling concept that is unique in Switzerland was developed. Using the foundation slab as a heat sink and heat source represents an alternative to the current heating systems for office buildings. The regeneration of the foundation slab in winter as well as in summer is mainly guaranteed by PVT collectors. The HVAC concept is designed to use as much of the internal heat (servers, commercial refrigeration, etc.) as possible directly for heating purposes.

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Sol-Ind Swiss – Solar process heat in the Swiss market

In Switzerland the industry share of the total energy demand is 19 %. Half of this energy is used for the conversion to process heat and is mainly provided by fossil fuels [SFOE, Swiss national statistics 2014]. In a feasibility study the use of solar process heat by systems with solar thermal collectors therefore shows great potential and will in more detail examine the integration in the energy supply systems. In this study we restrict to a temperature range below 130 °C. For this purpose, it is necessary to identify the Swiss companies, which have the majority of the thermal energy consumption at temperatures below 130 °C. Furthermore, within the framework of the project, standardized system solutions for the planning and integration of a solar thermal system will be developed on the basis of three case studies. The focus lays on the yield calculation of the plant taking the location into account, the costs for the collector field and integration as well as the CO₂ savings by replacing fossil fuels through solar energy.

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Siphon – Recommendation for heat traps of thermal energy storages

The installation of heat traps is state of the art for pipes that are connected to thermal energy storage units but that are not permanently operated, i.e. the fluid in the pipe is not flowing continuously. In this project, the SPF investigates on issues that created uncertainty within the planning and installation community, such as the question of the significance and effect of insulation in the region of the actual heat trap.

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Abstorex – Seasonal thermal storage system for solar energy

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).

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PVT Wrap-Up – Energy Systems with Photovoltaic-Thermal Solar Collectors

Photovoltaic-Thermal (PVT) solar collectors simultaneously generate useful solar heat and electricity and thereby reach high area specific energetic yields. In the past few years, an increasing interest in PVT collectors could be observed. New products were developed and brought to the market and, particularly in Switzerland, a number of PVT plants were built. On behalf of EnergieSchweiz (a programme by the Swiss Federal Office of Energy) SPF is leading a study on the current PVT market, the state of the art of PVT technology, and on the experiences made by the various actors that have been involved in the realization of PVT plants.

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ErrEnEff – Influence of individual room controllers on the heating demand of a single family house with low temperature heating distribution

In Switzerland standards allow floor heating systems without individual room controllers, as long as the calculated design flow temperature is below 30 °C. The argumentation is that a self-regulating effect comes into operation, because of the low temperature differences between heating surface and air temperatures. In the master thesis of Igor Mojic (part 1), it was investigated, whether the use of thermostatic valves leads to energy savings in the case of heat distribution systems with low flow temperatures. Based on the master thesis a second study was done with inputs from the AWEL Zürich (part 2).

This project is supported by the AWEL Zürich, department of Energy.

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Slurry-HP – A feasibility study to use a super-cooling ice slurry heat pump for solar heating applications

The goal of the present project is to analyse the technical and economic feasibility of a solar-ice system based on a super-cooling slurry heat pump. The system should achieve higher electricity savings and overall system performance with a comparable return on investment with respect to state-of-the-art ground source heat pump and solar-ice solutions. The anticipated efficiency increase is based on the super-cooler heat exchanger which is always free of ice. The anticipated cost reduction is based on the use of very simple storage vessels that do not need build-in heat exchangers.

Slurry-HP is financed by the Swiss Federal Office of Energy (SFOE).

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ImmoGap – Influence of user behaviour and building system technologies on the performance gap of large buildings

This project analyses multifamily homes that show a large gap between the predicted and the achieved energy performance, and determines the cause for these performance gaps. The combined effects of user behavior and the building technology and control are analyzed. From this analysis, options for action for planers and pubic authorities are deduced.

ImmoGap is supported by the Swiss Federal Office of Energy (SFOE).

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SWSG – Feasibility of solar assisted district heating networks in the canton of St.Gallen

Solar assisted district heating is widely used in countries as Austria, Germany and Sweden and is booming in Denmark. Heat production costs below 0.05 CHF/kWh where recently reached. With this feasibility study district heating networks of the canton of St. Gallen are analyzed in terms of the feasibility and the cost-benefit ratio of an integration of large solar thermal collector field. A further goal is to make contact between collector manufacturers and network operators as well as to initiate the realization of several large collector fields.

SWSG is supported by the canton of St.Gallen and the Swiss Federal Office of Energy (SFOE).

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ReSoTech – Reduction of Market Prices of Solar Thermal Systems due to New Technological Approaches – Phase 1: Analysis of Potentials and Possible

The potentials of cost reduction of solar thermal systems will be derived with cost data that will be gathered from field installations. The use of new technologies and materials for the exploitation of relevant potentials for cost reduction will be assessed. System concepts with reduced costs will be designed, which will contain newly developed components and which will have a high degree of faultlessness during installation and operation.

This project is financed by the Swiss Federal Office of Energy (SFOE).

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CombiVolt – Influence of smart heat pumps on PV self-consumption and on the electrical grid

Several companies develop or already offer «smart heat pumps» on the market which combine heat pumps (HP) with photovoltaics (PV). These heat pumps are advertised to optimize self-consumption of the PV electricity as well as to deliver grid services to the utilities. In the CombiVolt project, the influence of intelligent control for heat pumps on both (self-consumption and grid-stability) is analyzed based on whole system testing in the lab in combination with simulations. The options to increase self-consumption by means of electrical or thermal storage are compared. Thereby the current tariff-schemes of today are considered as well as future scenarios for PV penetration and electricity tariffs.

CombiVolt is supported by the Swiss Federal Office of Energy (SFOE).

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SCCER EIP – Industrial process heat with renewable energy sources

In order to push the energy transition seven Swiss Competence Centers for Energy Research (SCCER) have been launched by the Commission for Technology and Innovation (CTI). One of them, the SCCER EIP (Efficiency of Industrial Processes), focuses on the question of how to support industry to enhance the energy efficiency and reduction of CO₂ emission in order to reach the goals of the Swiss national «Energy Strategy 2050». The SPF is part of this consortium and supports industry partners in better management of energy consumption by energy flow analysis and by the investigation on the integration of renewable energy sources for process heat.

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EvaSP – Evaluation of solar process heat systems

The interest in solar process heat for industrial applications is increasing worldwide. For future perspectives and realization of further solar collector fields an assessment of the current state is necessary.

Within the framework of the project EvaSP (Evaluation of solar process heat systems) funded by the Swiss Federal Office for Energy SFOE, several solar collector fields used for processes heat in different industrial branches are energetically and economically evaluated. This project will give an overview of the performance of these collector fields as well as suggestions for suppliers and planners. Furthermore, the results of this evaluation will aid entrepreneurs and investors in the decision-making process and support the implementation of solar thermal energy in industry.

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SolProof – Compactness and fault resistance of solar heating systems

The competition between photovoltaics and solar thermal systems for available roof area and investment capital of house owners is putting pressure on solar thermal heating systems to reduce cost and to simplify the product. This project aims to assist manufactures in this task. The goal is to reduce the complexity of solar thermal systems, and reduce likelihood of failures during planning and installations. Criteria for defining compactness and fault resistance will be defined and subsequent applied to different heating systems in the test bench. For this purpose, the well-established CCT method will be simplified and combined with the criteria for evaluation of compactness and fault resistance.

This project is financed by the Swiss Federal Office of Energy (SFOE).

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IceEx – Characterization of heat exchanger concepts for ice storages

Ice storages in combination with solar thermal collectors and a heat pump to provide domestic hot water and space heating demands (solar-ice systems) are a promising technology. The project IceEx aims at characterizing heat exchanger concepts for ice storages in solar heating applications. Several heat exchangers, available on the market or recently developed for solar-ice systems, are analyzed by means of experiments and simulations to find an optimum design. Transient yearly simulations are used to assess the system efficiency and energy demand.

This project is financed by the Swiss Federal Office of Energy (SFOE).

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ColourAge – Lifetime assessment of aluminium based absorber coatings

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).

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Sotchà – Three different solar assisted heating systems for ground source regeneration

In this P&D project three identical minergie-A multifamily houses where equipped with three different solar assisted heating systems: PV, PVT and solar thermal with flat plate collectors. The heating systems are equipped with ground source heat pumps and controlled by a newly developed predictive and adaptive control. In the buildings with solar thermal plant the ground source is regenerated. The third building with PV and ground source without regeneration serves as a reference system. Temperature sensors at a depth of 50 m, 110 m and 170 m allow the evaluation of temperatures in the ground over time for each of the three borehole fields. The aim of this three years monitoring project is to identify improvements in the entire heating system of all three buildings and investigate the potential of various solar systems regarding the regeneration of ground sources.

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Oberfeld – Large PVT plants for ground source regeneration

In this P&D project the potential of large PVT plants used for ground source regeneration is studied. The complex Oberfeld consists of three buildings. Each of the three buildings has its separate heating system containing heat pumps, earth probes and a PVT solar plant. The PVT plant is one of the largest of its kind in Switzerland. The entire PVT plant consists of a total of 799 PVT collectors and has an overall area of more than 1300 m², distributed over the roofs of the three buildings. The heat from the PVT plant is primarily used for ground source regeneration, but it can also be used to provide heat directly for the evaporator of the heat pump.

Within this 5 years P&D project the interaction of the entire heating system will be optimized and the long term temperature development and behavior of the ground source with solar regeneration will by observed.

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THRIVE – Thermally driven adsorption heat pumps for substitution of electricity and fossil fuels

This project focuses on the use of a thermal driven adsorption heat pump using waste heat stemming from industrial processes.

This project is supported by the Swiss National Science Foundation (SNSF). IBM research is leading the umbrella project; in addition to the SPF (adsorption heat pump development), the EMPA (Building Energy Materials and Components), the ETH Zürich (Complex Materials), the HEIG-VD (Solar Energetics and Building Physics) as well as the PSI (Technology Assessment Group) are implied in subparts of this project.

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COMTES – Combined development of compact seasonal thermal energy storage technologies

COMTES main purpose is the development and demonstration of various techniques enabling to store heat over a long period (seasonal storage) with a high energy density and with less losses than conventional water storage. This should enable to increase the building heat solar fraction coverage.At SPF, investigation are lead on an absorption/desorption concept using sodium hydroxide (NaOH) and water as thermochemical heat storage mediums.

EMPA and Kingspan Renewables are SPF main project partner in this subproject line. The project is supported European Union's in the frame of the FP7 Research and Innovation funding programme (FP7, Project no. 295568).

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