immo!nvest – Die Plattform für Standorte und Immobilien

Tag: Begrünung

  • Sursee makes solar systems and green roofs standard

    Sursee makes solar systems and green roofs standard

    In future, the roofs of new buildings or roof renovations in the municipality of Sursee are to be fitted with solar panels. For flat roofs, the aim is also to green them. This was decided by the Sursee municipal council on 14 October with the majority approval of a counter-proposal to the municipal initiative for an independent and ecological energy supply (solar initiative). The initiative committee had withdrawn the solar initiative after the city council had drafted the counter-proposal.

    The counter-proposal is in line with the new cantonal energy law, which will come into force on 1 March 2025, subject to a referendum. New buildings will then have to be equipped with 60 per cent solar panels, and 30 per cent for roof renovations. If the requirements are not met, a replacement levy of CHF 1,000 per kilowatt will be due. In deviation from cantonal law, this levy will only be possible in Sursee if the construction and operation of the solar system is economically unreasonable.

    The new cantonal energy law does not specify any requirements for the greening of roofs. However, Sursee wants to use green roofs to improve the urban climate and as a substitute habitat for plants and animals. For this reason, a combination of green roofs and solar panels is being sought as standard on flat roofs.

    The solar utilisation of façades called for in the solar initiative is not provided for in the counter-proposal. The city council feared that this would have a negative impact on the townscape. In addition, the cost-benefit ratio of façade systems is currently even worse than that of roof systems.

  • Energy generation and cooling: façades at the centre of research

    Energy generation and cooling: façades at the centre of research

    HSLU researchers have explored the potential for greenery and solar panels on building façades in the GreenPV project. “While the benefits of PV systems and greenery are already being increasingly utilised on roofs, they have largely not been used on façades to date,” HSLU researcher Silvia Domingo is quoted as saying in a press release issued by the university about the project. However, they could contribute to closing the gap in winter electricity, among other things. This is because “the energy yield of a PV system is higher on a south-facing façade in the winter months than on a roof due to the low angle of inclination of the sun caused by the season”, explains Domingo.

    In addition to their cooling effect, green façades also contribute to biodiversity and the reduction of sound propagation. Air quality is also improved through the binding of pollutants and the production of oxygen. According to the HSLU researchers, greenery and photovoltaics (PV) can be combined well on façades. “PV comes into its own where a high level of energy generation is possible, i.e. on an unshaded façade on the upper floors,” says Domingo. Greenery, on the other hand, should be installed on the lower storeys and in inner courtyards.

    The authors have identified financing and a lack of guidelines and experience as obstacles for building owners. The appearance of a façade completely clad in black solar panels is also not to everyone’s taste. For this reason, the HSLU has already tested alternative colours and textures in another project.

  • Study shows opportunities for façade greening and solar panels

    Study shows opportunities for façade greening and solar panels

    As part of the GreenPV project, a research team from Lucerne University of Applied Sciences and Arts has developed innovative solutions for the design of building façades. The aim was to explore the potential of photovoltaic systems (PV) and greenery in order to meet the increasing challenges posed by global warming. A brochure specially developed for planners and building owners summarises the findings and recommendations of the project.

    The importance of this research becomes clear when you look at the forecasts of the National Centre for Climate Services: The average annual temperature in Switzerland could rise by up to 5.4 degrees by the end of the 21st century. This will not only significantly increase energy requirements, particularly for cooling, but will also affect comfort levels in buildings. Photovoltaic systems can supply energy precisely when it is needed most, namely when the sun is shining intensely. At the same time, green façades offer a sensible alternative in urban areas where new green spaces are scarce.

    Façades as untapped potential
    “While the benefits of PV systems and greenery are already increasingly being used on roofs, façades have so far remained largely unused,” explains Dr Silvia Domingo, researcher at HSLU. Yet façades offer an excellent opportunity for energy generation and greening without taking up additional space. PV systems on south-facing façades are particularly efficient in the cold season, as they can make optimum use of the low angle of inclination of the sun.

    However, the study also shows that there are obstacles that stand in the way of a wider application of these technologies. These include financial challenges, a lack of guidelines and concerns about fire safety. These factors often cause uncertainty among building owners. To counteract this, the research team has produced a brochure with practical recommendations for the use of PV systems and greenery on façades.

    Visual aspects and functional synergies
    Another obstacle identified by Dr Domingo is the aesthetic perception of solar panels on building façades. Black solar panels often do not meet the visual expectations of building owners. However, research shows that solar panels in different colours and textures could also be available in the future without any significant loss of efficiency.

    In addition to PV systems, green façades offer numerous advantages that go far beyond the cooling effect. They contribute to biodiversity, improve air quality, reduce sound propagation and promote rainwater retention. These benefits are particularly important in densely built-up urban areas, where they can significantly improve the quality of life.

    The combination of greenery and PV systems
    The HSLU study shows that greenery and PV systems on façades can often be combined well in order to utilise synergies. While PV systems on unshaded, higher façade areas ensure maximum energy generation, green areas near the ground have a cooling and noise-absorbing effect. This combination contributes to a more pleasant neighbourhood climate and climate-friendly electricity production.

    Completion of the GreenPV project
    The GreenPV project, which started in December 2021 and ran until mid-2024, was funded by a broad network of supporters, including the Swiss Federal Office of Energy (SFOE) and various foundations. The project team, led by Gianrico Settembrini, gained valuable insights, which are recorded in a brochure and are now available to planners, building owners and interested parties.

    With the results of the GreenPV project, the HSLU is making an important contribution to sustainable development in the construction industry and demonstrating how greenery and solar panels on façades can be combined to effectively meet the challenges of climate change.

  • Bern is to get the greenest alley in Switzerland

    Bern is to get the greenest alley in Switzerland

    The Institute of Plant Sciences at the University of Bern wants to contribute to coping with climate change and biodiversity loss. To this end, the institute is tackling a project in Bern’s old town together with business partners and residents. Here, the Postgasse, a listed building, is to be transformed into the greenest alley in Switzerland, the University of Bern informs in a statement.

    “We are supporting residents in greening their own windowsills and outdoor areas with suitable plants,” project initiator Matthias Erb is quoted as saying in the statement. Afterwards, the researchers from the University of Bern want to study the effects of greening on the ambient temperature, biodiversity, water balance and quality of life in the Postgasse. “The collected data and experience from this pilot project should help Bern and other cities in the future to increase their sustainability and attractiveness even more quickly and easily,” explains Armin Komposch from the Institute of Plant Sciences.

    The companies Baumschule Gartenpflanzen Daepp, Ricoterand Zollinger Bio are contributing plants, seedlings and soil to the project. Plant containers with automatic irrigation are contributed by Boum AG. The young Bernese company was founded in 2021 as a spin-off of the University of Bern.

    The official start of the project is a planting day on 6 May. Here, interested residents can pick up plants, soil and pots to green the Postgasse as they see fit. The residents themselves are to take over the subsequent maintenance.