The city of Frauenfeld is pursuing the ambitious goal of becoming climate-neutral by 2050. An important milestone on this path is the complete phase-out of fossil fuels for heating by 2040. Today, around 80% of buildings in Frauenfeld are still heated with oil or gas. This dependency poses major challenges for the city and its utility company, Thurplus, in terms of security of supply and economic efficiency in the transition to renewable energies.

In order to tackle these challenges, Thurplus initiated the project Energy Perspectives Frauenfeld 2050 in spring 2023, which is led by Empa's Urban Energy Systems Lab under the direction of Matthias Sulzer and Georgios Mavromatidis and supported by the expertise of Empa spin-off Urban Sympheny in the field of energy systems modeling. By combining Thurplus data from around 20,000 smart meters, electricity and gas meters and statistical building data with state-of-the-art energy optimization models, the project identified realistic and cost-efficient solutions for a climate-neutral future.

In close cooperation with Thurplus, scenarios from the Energy Future 2050 study by the Association of Swiss Electricity Companies (VSE) were adapted specifically for Frauenfeld. These scenarios show which technologies, energy requirements and infrastructures are necessary to achieve net-zero emissions.

Economic efficiency can be achieved through coordinated planning: Coordinated planning and implementation that takes into account the local conditions of the neighborhoods in Frauenfeld reduces the overall costs of the energy system and shows that a renewable energy supply is economically viable. Nevertheless, a considerable investment is required, and it is crucial that the necessary financial resources are available.

The Energy Perspectives Frauenfeld 2050 project recommends the coordinated expansion of climate-friendly technologies such as district heating, heat pumps, photovoltaic systems, electric vehicles and battery storage, while at the same time consistently pursuing the energy-efficient renovation of buildings. Moreover, careful planning of electricity and heating grids in line with the net-zero pathway is required, as well as flexible solutions such as energy storage and intelligent energy use by consumers.

The results show how data-based models and cross-sector collaboration can help cities develop robust, economical and sustainable strategies for the energy transition. They provide a solid basis for decision-making for politicians, utility companies and citizens and serve as a model for other Swiss municipalities on the path to climate neutrality.

The results of these energy perspectives now form the basis for general energy planning and, more specifically, for the revision of the energy master plan, the further expansion of district heating and electrical grid planning for the city of Frauenfeld. The project was supported by the Swiss Federal Office of Energy (SFOE), the Office for Energy of the Canton of Thurgau and the Office for Building Construction and Urban Planning of the city of Frauenfeld.

More and more people are moving to cities, which means more traffic, denser living and less space for parks or other green areas. As a result, the urban population is exposed to more and more noise and has fewer opportunities to relax in natural environments. A study by Empa and the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), funded by the Swiss National Science Foundation (SNSF), now shows how great the potential of urban green spaces for recreation and stress management actually is. “Noise-stricken city dwellers can recover much better if they live near green spaces or in green environments. This effect can be seen on both a physical and mental level - and is even demonstrable in the long term,” says Empa researcher Beat Schäffer, summarizing the main findings. “The negative impact of noise on people can therefore be compensated to a certain extent by green spaces.”

The results from the laboratory were also confirmed in a field study. Empa researchers visited more than 230 volunteers in the city of Zurich who live in environments with varying degrees of noise pollution and greenery. They documented the participants' surroundings with photos, took hair samples to measure the stress hormone cortisol and asked them how they felt. “Both the interviews and the laboratory analyses of the hair samples showed that green spaces in the neighborhood actually promote relaxation,” says Beat Schäffer. The restorative effect of green spaces is therefore not only short-term, but also reduces long-term stress.

In addition, WSL researchers conducted a representative survey to determine how well the Swiss population can relax in the green spaces in their neighborhoods and what role noise pollution plays in this. On accompanied walks, they also investigated which audiovisual features are particularly conducive to relaxation. The results of the four sub-studies are now being combined to determine the recreational potential of green spaces and their contribution to public health. According to Empa researcher Schäffer, this so-called RESTORE project (“Restorative green spaces in noise-polluted areas”) is unique and addresses a relevant topic that affects three quarters of the urban population in Europe. “It will provide important information for legislators and spatial planners and influence Swiss noise legislation and the implementation of the revised Spatial Planning and Environmental Protection Act.”