"Sustainability is no longer an additional issue for companies today, but a competitive advantage that brings ecological and economic benefits," said Patrik Meli. The Managing Director of Everllence thus made it clear that the energy transition is not just the result of climate policy, but is also being driven forward by the industry - because it is worthwhile.

Everllence (formerly MAN Energy Solutions) sees itself as the driving force behind this change. The company supplies technological solutions that a sustainable energy system depends on: compressors are now not only built for the oil and gas industry, but are also increasingly being developed for large heat pumps. In view of the technological progress that has made the boom in heat pumps possible, among other things, Martin Neukom, President of the Zurich Cantonal Council, stated: "The conditions for climate protection have never been as good as they are today."

At the same time, however, he warned that Europe was in danger of being left behind: China installs as many solar panels and wind turbines every year as the rest of the world combined. "Europe's economy will not survive as an industrial museum of the 20th century," said Neukom. Industry, politics and society must therefore join forces to drive forward innovations for decarbonization

Flexibility as the key to stability

Energy systems expert Martin Wietschel, professor at the Fraunhofer Institute, emphasized that Europe should focus on strategic fields in the energy transition: "We can no longer promote all technologies equally, because Europe is relatively expensive."

Wietschel spoke about the electricity system of the future and pointed out that the increasing demand for energy requires more energy efficiency and flexible use of electricity. One thing is clear: "Base-load power plants no longer fit into a system with many renewables." It will no longer be worth operating such power plants as a stopgap for the lack of solar power in winter. However, a sustainable energy system only works if the interaction between renewables and energy storage is based on the greatest possible flexibility - both production and consumption.

Heat storage systems still need to establish themselves

In terms of system flexibility, however, there is still room for improvement, as Anastasia Stamatiou, Professor of Thermal Energy Storage at Lucerne University of Applied Sciences and Arts, emphasized. Although heat accounts for 50 percent of energy consumption, it is often forgotten in storage strategies: "Far too often, energy storage is used as a synonym for battery storage."

Inexpensive systems that provide heat flexibly already exist today: In Denmark, for example, mine storage tanks - well-insulated water basins - support the district heating network. And decentrally installed latent heat storage systems are a cost-effective way for individual consumers to use renewable energies flexibly.

This model offers enormous potential for industry in particular: process heat is responsible for around 8 percent of Swiss greenhouse gas emissions. In combination with high-temperature heat pumps and electric heating elements, heat storage systems could make a major contribution to decarbonization, explained Stamatiou: "Thermal energy can relieve the electricity grid by generating and storing it when electricity is cheap."

IronEnergy: Seasonal electricity storage at low cost

Samuel Heiniger, founder of the start-up Iron Energy, developed a particularly uncomplicated and inexpensive energy storage system during his doctoral thesis at ETH Zurich: A container full of rusty iron.

The idea behind it: If hydrogen is generated using electricity and fed into the container, the iron oxidizes. If the hydrogen is to be available again later, the iron reacts with water vapor - the hydrogen can then be converted back into electricity.

The start-up is currently working on a pilot project: an iron storage facility the size of a shipping container is to close the winter electricity gap for around 100 households. The system is worthwhile despite its low efficiency. This is because it uses electricity that is often considered "waste" today. Around 27 percent of solar power is sold at negative prices in summer.

Sustainability as a locational advantage

Patrik Meli from Everllence confirms that the industry still has some catching up to do in the area of heat: "We are looking into how we can not only release the heat we generate into the environment, but also use it."

Despite simple and inexpensive technology, heat storage systems are finding it difficult to establish themselves, as Anastasia Stamatiou emphasized. "It wouldn't hurt if the gas price were higher." System specialist Martin Wietschel also confirms this: "Only a sufficiently high CO₂ price will give alternative energy storage systems a real chance compared to conventional gas storage systems."

Markus Müller, Co-Head of the Division of Business and Economic Development of the Canton Zurich, emphasized that sustainability has an impact beyond the immediate economy: "Companies are increasingly interested in the availability of sustainable energy in order to meet their own climate targets." Energy has therefore become an important argument when it comes to locating a company. And Müller is convinced: "In combination with bright minds who develop smart technologies, we offer a strong ecosystem in Zurich."