immo!nvest – Die Plattform für Standorte und Immobilien

Tag: Wärmespeicher

  • Compact heat storage system wins innovation award for energy solutions

    Compact heat storage system wins innovation award for energy solutions

    The international jury of the SET Award 2025 has chosen Cowa Thermal Solutions as the winner in the Clean Energy & Storage category. The SET Award promotes innovative ideas and solutions for a sustainable energy future and thus accelerates the energy transition.

    The competition is announced and organized worldwide by the German Energy Agency in cooperation with the World Energy Council. It is supported by the German Ministry of Economic Affairs and Climate Protection. The award recognizes innovations that drive forward the global energy transition. The award ceremony took place as part of the SET Tech Festival 2025 in Berlin.

    As the organizers point out in a press release, Cowa is developing “compact heat storage systems with phase change materials that are five times smaller than water-based systems. With the aim of serving the growing European heat pump market, Cowa is improving the integration of renewable energy and urban energy efficiency.”

    In a press release issued by his company, which was founded in 2019 and is based in Technopark Lucerne, Cowa CEO Simon Maranda describes this award as “a great recognition of our work and commitment to innovative energy storage solutions. Our compact thermal energy storage systems are an ideal solution for integrating renewable heating systems, especially heat pumps, in urban buildings with limited space. We are proud to continue to drive this technology forward and play an active role in shaping the energy transition.”

    Once again this year, pioneering start-ups were honored in five categories: Clean Energy and Storage, Mobility & Transportation, Industry, Buildings & Construction and Access to Quality Energy & SDG-7. The winners of all five categories also presented their solutions at the Berlin Energy Transition Dialogue afterwards.

  • Thermochemical storage optimises solar energy use

    Thermochemical storage optimises solar energy use

    Lucerne University of Applied Sciences and Arts and its industrial partner Matica have developed a technology that allows surplus solar power to be stored without loss in a thermochemical process in summer and used for heating in winter. A first pilot plant has now gone into operation at the animal carcass collection centre (TKS) in Frauenfeld, Matica announced in a press release. The Wagenhausen-based company specialises in the construction of special containers such as water heaters and heat and cold storage tanks.

    The SeasON demonstration plant in Frauenfeld uses caustic soda as a storage medium. In summer, the caustic solution is concentrated using surplus electricity from the TKS solar system and the separated water is stored in separate tanks at room temperature. In winter, the concentrated lye is diluted again with the separated water. This is vaporised using low-temperature heat from a heat pump. Both this vaporisation energy and the heat generated from the exothermic reaction when the lye is diluted can be used for heating. The storage efficiency of the system is put at up to 95 per cent in the press release.

    “SeasON solves several challenges of the energy transition at the same time and promotes sustainable, efficient energy management,” Benjamin Fumey from Lucerne University of Applied Sciences and Arts is quoted as saying in the press release. “In the development of SeasON, we have mutually conditioned each other and at the same time created a win-win situation between research and practice,” says Matica CEO Marc Lüthi. A second demonstration system is currently being installed in the new Swiss Post delivery centre in Kaltenbach TG.

  • Sustainable processes through pinch analysis and heat storage

    Sustainable processes through pinch analysis and heat storage

    Lucerne University of Applied Sciences andArts (HSLU) has developed the PinCH software, which can be used to make industrial processes more energy-efficient and economical. According to a press release from the university, the latest version of PinCH 4.0 can also integrate open-loop heat storage systems. A pinch analysis can be used to systematically show how thermal energy flows need to be coupled in order to achieve high energy efficiency with minimal overall costs (consisting of investment and operating costs).

    PinCH 4.0 has already been used to analyze the production processes of the food manufacturer HACO in Gümligen BE. The analysis showed that the use of hot water steam required for process preparation can be reduced by half with an open-loop heat storage system.

    “If process streams, such as the brewing water in a brewery or the process water at HACO AG, are used directly as a storage medium, heat exchangers and intermediate circuits can be saved”, explains Donald Olsen, Project Manager PinCH Software Development at HSLU, in the press release. “Such an open-loop storage system increases the energy-saving potential, simplifies the system and thus reduces energy and investment costs.”

  • New white paper: ‘Energy storage systems for properties: Using renewable energy efficiently’

    New white paper: ‘Energy storage systems for properties: Using renewable energy efficiently’

    Link to the whitepaper

    Switzerland is aiming for a target of net zero by 2050. This means replacing fossil-based energies with renewables. However, the output from systems is dependent on weather conditions, the time of day, and the season. Getting supply and demand in sync calls for storage solutions. This also improves the property’s carbon footprint, because it requires less oil or gas to cover peak loads.

    Electricity storage systems: battery-powered flexibility
    Battery storage systems can temporarily store surplus solar power locally and supply household consumers, electric vehicles or the heat pump later on. This significantly increases the level of self-consumption and with it the cost-efficiency of solar power plants. Not only the operator benefits from a storage system – the electricity grid does as well. This means, for example, that when a solar power plant produces a surplus, it doesn’t have to be shut off for fear of overloading the grid. And in the reverse scenario – when demand outstrips supply – locally stored energy can help cover peak loads, which stabilises the grid and keeps costs low. Currently the standard means of electricity storage is the lithium-ion battery, while alternatives such as sodium-ion batteries and salt batteries have yet to become established. This also applies to bidirectional charging, in which the battery of an electric vehicle is used for local electricity storage.

    Heat storage units: geothermal probes and containers
    One alternative to storing surplus solar power is to transform it into thermal energy. Heat can be stored over weeks or months and used later for heating and hot water supply as required. This makes heat storage a great fit with renewable heating systems such as heat pumps and thermal networks. And some types of storage system can be used as heat sinks in summer to cool buildings with minimal use of energy. The most common storage types in Switzerland are geothermal heat storage units and container heat storage units. One interesting variant that requires less space is ice storage.

    Hydrogen and methane: seasonal storage
    Another way to store surplus solar power seasonally is to transform it into a carbon-neutral gas like hydrogen or methane (‘power-to-gas’). If required, the gas can be used either to produce heat and electricity or as a fuel for vehicles. Hydrogen is produced through the electrolysis of water, and the degree of efficiency in this transformation is up to 80 per cent. Transforming it further into methane has the advantage that it can be stored in the natural gas grid, so it doesn’t require separate infrastructure. The overall degree of efficiency depends on the method used, but with a current best-case result of 50 to 70 per cent, it is not yet cost-effective.

    You can find much more information and real-life examples in the new ewz white paper ‘Energy storage systems for properties: Using renewable energy efficiently’.

  • Zurich Airport wants to use ice age channel for air conditioning

    Zurich Airport wants to use ice age channel for air conditioning

    Flughafen Zürich AG is currently exploring an ice-age gully beneath the airport. It is 300 metres deep and around 30 kilometres long in total. As it is filled with water-bearing gravel, it could be used to store heat and cold in order to heat and cool a significant proportion of the airport buildings without emissions.

    “By moving away from fossil fuels such as oil and gas, we are coming much closer to our goal of achieving zero greenhouse gas emissions by 2040,” said Lydia Naef, Chief Real Estate Officer of Flughafen Zürich AG, in a press release. “Geothermal energy plays a central role in this.”

    Together with IG Rinne, a consortium consisting of engineering consultants Geo Explorers, Sieber Cassina & Partner AG and E-Axiom GmbH, Flughafen Zürich AG is working on a multi-stage process to analyse the potential of the gutter as a storage facility. The results of the investigation to date are said to be promising.

    If successful, Zurich Airport intends to utilise the channel as a heat and cold storage facility from 2026. It estimates the investment costs for researching the channel and constructing the wells at between 4 and 8 million Swiss francs, depending on the number of wells required. In addition, there would be development costs for pipelines and other technical measures.

    The project is being funded and supported by the Swiss Federal Office of Energy as a pilot project, says Emanuel Fleuti, Head of Sustainability and Environment at Flughafen Zürich AG. “We are making all the findings available to the scientific community and can thus make a contribution to research into emission-free cooling and heating systems.”

  • Cowa Thermal Solutions develops highly efficient heat storage system

    Cowa Thermal Solutions develops highly efficient heat storage system

    Cowa Thermal Solutions has developed a method that can increase the capacity of heat storage units for combined photovoltaic-heat pump systems many times over. The founders of the start-up from the canton of Lucerne already researched this technology for heating and hot water as part of their master’s thesis at the Lucerne University of Applied Sciences and Arts.

    According to a statement from the university, they then worked for another four years to make their product, the cowa booster storage tank, ready for the market. During the past heating season, it was tested intensively in the field. The tests showed that the cowa technology doubled the autonomy of the heating system and halved the dependence on the electricity grid. The cowa Booster Speicher is now available in stores. The sales partner is the building technology company Meier Tobler. Initial talks for expansion into Germany and Europe are reportedly underway.

    According to the Lucerne University of Applied Sciences and Arts, it increases capacity without taking up more space. “The core of our technology is the storage material,” explains cowa founder and co-CEO Remo Waser. “It is based on cost-effective salt hydrates, whose storage density is up to three times higher than that of water. Our heat storage units are correspondingly more powerful.”

    The salt hydrates are reportedly in capsules. The storage tank is filled about 40 per cent with heating water and 60 per cent with capsules containing the salt hydrates. “In this way, the cowa buffer storage tank can store two to three times more energy than a conventional water storage tank of the same size without capsules,” says CRO Jan Allemann.