SWEET EDGE: a project to boost Switzerland’s climate goals

In June 2021, the Federal Office of Energy has launched the SWEET incentive program (Swiss Energy Research for Energy Transition). It aims to promote the innovations necessary for the implementation of Switzerland’s 2050 Energy Strategy and its new objective of climate neutrality. 30 million francs have been allocated to fund 4 projects based on collaboration between research establishments, the private sector, and public authorities. SWEET-EDGE has been selected and is the first large research project facilitated by CLIMACT. It involves 15 research and more than 50 other partners and is co-led by Prof. Evelina Trutnevyte (University of Geneva) and Prof. Michael Lehning (EPFL).


Interview with Prof. Michael Lehning, CLIMACT Academic Co-Director


SWEET-EDGE stands for “Enabling Decentralized renewable GEneration in the Swiss cities, midlands, and the Alps”. It has been launched two weeks ago. Can you describe the project in a few words?


Prof. Michael Lehning: In the future, in a renewable Switzerland with no more nuclear power generation and in a context of high market uncertainty, we think that bringing consumers and producers closer together on a regional level has the most potential. That means that to a certain extent, you can decouple regional units from a global European or Swiss context and encourage people to invest, as well as produce and consume energy in their own environment.

Decentralized generation is interesting from a market and financial perspective, but more fundamentally, it is a necessity.

If we talk about biomass, wind, and solar renewable resources, by the very nature of the generation, it will be decentralized.



What is the challenge with decentralized generation?


Prof. Michael Lehning: Wind and solar energy are low density elements, and you must consider the spatial domain. It’s not the same as a nuclear power plant that has a spatial radius of a kilometer, here you have to use much land to produce enough energy through wind and solar to replace those nuclear power plants and the rest of the fossil fuel that we are still using.



What makes this project unique?


Prof. Michael Lehning: Its interdisciplinarity. Today, we are stuck: the technologies are largely known but there are still lots of details that we ignore. We don’t know where we have the best wind or solar potential in the high mountains and how to deal with the harsh and snow environment. This is something that we cover with this project. But the real uniqueness comes from the fact that we are addressing altogether grid stability, existing infrastructure constraints, social acceptance, financial questions and legal frameworks. All this is needed for the implementation. Everything is there, from the technical to the socio-economic aspect. And this is exactly where we feel things are not moving forward.

The science, the engineers have so far failed to draw solutions that the politicians can comprehend and implement. If you only look at certain technical aspects, you can say photovoltaics in the mountains is the solution. However, if you don’t show how it can be financed, what is acceptable to those people who rightly want to protect the landscape, or what makes sense in a local context to come to stable operation and match supply and demand, it’s useless.



What results do you hope for?


Prof. Michael Lehning: It’s a long-term investment. The project itself runs for 6 years. We have the very high ambition to use that as a backbone to launch Pilot and Demonstration projects with fairly large installations to see in the field how such a system can work. Ideal would be to have a few large generation plants of wind and solar operating in the mountains and have a cool pilot region in the midlands, where you can study how biomass is used, how we can achieve additional storage and supply demand efficiently. These things are currently planned and set-up.

In the city, it is different because we know that we cannot produce enough renewable energy locally and in a decentralized way. So, there will always be some import required, but that could come from the Alps, where we know we have enough to export, not only via hydropower but also other sources.

The ambition is that at the end of the project, we have blueprints for solutions for all these landscape elements that can be upscaled to help all of Switzerland to be successful in the energy transition.

The real uniqueness of the project: we are addressing altogether grid stability, existing infrastructure constraints, social acceptance, financial questions and legal frameworks.“

–Prof. Michael Lehning I CLIMACT Academic Co-Director


More about the project:

This joint EPFL-UNIGE consortium, co-led by Prof. Evelina Trutnevyte at the University of Geneva and Prof. Michael Lehning at EPFL, will work on fast-tracking and integrating very high shares of locally-sourced renewable energy supply in the Swiss system. The EDGE consortium will move beyond generic designs of decentralized renewable systems and markets to a regionalized analysis that is tailored to the Swiss cities, midlands, and the Alps.

The consortium will combine research with innovation in three clusters of Pilot and Demonstration projects in urban settings (the cantons of Bern, Luzern, and Aargau), midlands (Waldkirch, the canton of St. Gallen), and the Alps (Davos and Bagnes-Verbier, in the cantons of Graubünden and Wallis).  With overall costs of over 22 million CHF in 2021-2027, SWEET-EDGE involves 15 research partners (energy technology, systems modeling, political science, management, economics, and sustainability science), 20 implementation partners from industry and public authorities with commitment, and over 40 other supporting partners.