Daniel Philippen

Heat storages can assist in the rational dimensioning and operation of thermal networks. They can smooth out peak loads and eliminate the need for fossil-fuelled peak load boilers. Heat surpluses can be stored temporarily. Decentralised storage systems can relieve the load on individual sections of the grid or enable grid densification and expansion. They are also ideal for the efficient integration of decentralised heat generators. This project aims to quantify potential cost and emission savings by implementing decentralised thermal storage systems in various district heating networks. The project will provide recommendations for the dimensioning and operation of these storage systems. Additionally, an Excel user tool will be developed to assist planners in determining the impact of storage systems on power distribution and thermal network costs.

A solar-ice heating system was designed and installed as part of a pilot and demonstration project. Since 2017, the heating system is supplying a residential and commercial building of 2050 m² of energy reference area with space heating and hot water. The main components of the heating system are 120 m² of unglazed, spectrally selective solar collectors, an ice storage tank with 210 m³ volume, and a two-stage brine-to-water heat pump with 45 kW thermal output (B0/W35). The heat exchangers in the ice storage tank are periodically de-iced in winter and could therefore be designed with a small transfer area.

The importance of hydraulic balancing of heat distribution systems for energy-efficient building operation and resident comfort has long been recognized. Nevertheless, it can be stated that there is a lack of expertise and still far too often insufficient implementations occur in practice. Companies have also noticed this gap and have developed new products or solutions. The aim of this research project is to investigate how well and reliably these solutions for automatic hydraulic balancing work, and what benefits they provide in terms of comfort and energy efficiency. For this purpose, the products will be installed in real systems and tested by means of a hardware-in-the-loop procedure. The effects on a virtual building modeled in detail can be tracked and evaluated in real time. The results are presented to the professional community in the form of factsheets that enable an independent comparison.

RENOWAVE is a flagship project of the Swiss Innovation Agency (Innosuisse). It aims to reduce the CO₂ emissions of the Swiss building stock by renovating buildings and switching from fossil fuels to renewable energies.

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.

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.

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.

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).

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.

The objective of the High-Ice project was to investigate a specific concept of a solar thermal and heat pump system with ice storage (solar-ice system). An ice storage design with heat exchangers that can be de-iced was studied. The dependence of the system’s electricity consumption on the sizing of the main components (collector field and ice storage) was analysed by means of simulations with the software TRNSYS. An important additional aim of the study was to analyse the system concept from an environmental and an economic point of view. Further, an elastic heat exchanger plate made of EPDM-rubber that can be de-iced mechanically by inflation, was developed on the laboratory scale.

High-Ice was supported by the Swiss Federal Office of Energy (SFOE).