immo!nvest – Die Plattform für Standorte und Immobilien

Tag: Warmwasser

  • 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.

  • The forgotten solar hot water systems

    The forgotten solar hot water systems

    In Switzerland, about 6% of all apartment buildings have a solar hot water system (solar thermal) in operation. These are used to heat hot water in order to reduce the consumption of oil and gas. Most of these systems were installed about 10 years ago, when photovoltaics were much more expensive. However, in recent years they have been forgotten. Many owners and administrators discover the installations only by chance through a view of the property on Google Maps, when they analyse the roof for photovoltaic suitability.

    On average, solar hot water systems have 20 years of operation ahead of them, during which they can generate CO2-free heat and also significantly reduce utility costs thanks to fossil energy savings. Because nobody knows about the existence of many installations, one in five is defective. This means valuable solar heat is being wasted and fossil fuel heating systems are having to step in instead.

    Several cantons have already recognised the problem and launched awareness campaigns to make owners, caretakers and administrators aware of the issue. The free solartest.ch platform has been created for this purpose in collaboration with Energie Schweiz and Swissolar. This allows users to check whether their system is running correctly by simply entering the temperature values they have read.

    To avoid having to read the temperature values every week, Energie Zukunft Schweiz has developed the LORALARM monitoring system, which can be retrofitted.

    As part of a project with a large Swiss insurance group, 65 existing solar hot water systems were monitored, of which a total of 15 systems were found to be out of order. Minor repairs enabled systems worth CHF 1.5 million to be put back into operation within a very short time.
    The good time to find out if your solar thermal system is running is on a sunny winter’s day. This ensures that the defect will be producing sun-warmed water again by the time of the productive spring days from the beginning of March, after any repairs have been carried out.

  • Bern has the most climate-friendly building stock

    Bern has the most climate-friendly building stock

    Navitas Consilium has developed an interactive tool to show the share of renewable or imported energy in the building stocks of each municipality in Switzerland, the Martigny-based energy and climate consultancy informs in a press release . The amount of greenhouse gases generated by the building stocks can also be called up using the tool. With its development, Navitas Consilium wants to help determine the need for decarbonization of building stocks for the implementation of the Swiss climate strategy.

    An interactive map can be used to show that the most densely populated areas of the country use a low proportion of renewable energy compared to rural areas. With a share of 28 percent, Lausanne is still the best of the ten major cities. For Switzerland as a whole, the values vary between 2 and 84 percent.

    At almost 40 percent, heating and hot water in buildings account for a very high proportion of total energy consumption. For the implementation of the climate strategy, Navitas Consilium therefore considers a reduction in energy consumption in combination with the use of low-emission renewable energies to be essential.

    The city of Bern is currently one step ahead when it comes to the climate-friendliness of its building stock. With 23 kilograms of CO2 equivalents per square meter per year, Bern has the lowest emissions of the ten largest cities in Switzerland. Zurich and Basel follow, each with 24 kilograms of CO2 equivalent per square meter. In general, cities with less than 10 percent energy from renewable sources have comparatively high emissions of greenhouse gases.