MIGROS receives the largest salt battery storage facility in Switzerland

"Now we are ready for great things," says Max Ursin, managing director of innovenergy and the project's mastermind. In a collaboration of six different companies from three countries, a 540 kWh salt battery storage system now stands in the basement of MIGROS Schlieren/ZH. Ecology and sustainability were the decisive criteria for this saline nickel technology. The purpose of the large-scale project: to save energy costs by optimising self-consumption and peak shaving. 

Everything starts in May 2020 with an offer from innovenergy and an award of the project from MIGROS at the end of July 2020. Planning begins in September 2020. A large photovoltaic system with 806 kWp was installed two years earlier by Alex Gemperle on the roof of the MIGROS branch. Energy data from two years are therefore available as a basis for calculation.

What is important?

Despite the supermarket's high energy consumption, the PV system produces large amounts of surplus, which has so far been fed into the grid at less attractive conditions. This should pay off better in the future. But this can only be done by using the self-produced electricity more intensively. In order not to have to supply this energy immediately, intermediate storage in the form of a battery is necessary. The challenge is to create an intelligent system that draws power from the battery and not from the grid when a certain amount of energy is needed. This so-called peak shaving attempts to balance consumption peaks in a sensible and cost-efficient way.

Decision criteria

MIGROS, as a consumer-oriented cooperative, is very concerned about ecology and sustainability in its entire corporate concept. Where possible, it tries to implement it consistently. The only sustainable alternative to the usual lithium-ion battery storage systems that can also provide such peak shaving performance are the molten salt batteries from the manufacturer FZSoNick in Stabio/TI. As a system builder for molten salt battery storage systems, innovenergy from Meiringen/BE is the sole contractual partner for this salt technology.

The topics of added value in Switzerland and safety for customers are also important aspects. Because this salt-nickel technology does not contain any toxic ingredients or ecological overexploitation. And it also works without Asia and overseas - entirely Swiss and in the close European environment. Salt batteries are also absolutely safe and cannot burn or explode. So customers can shop in an ecologically energy-optimised supermarket without any risk at all.

Implementation and assembly

From December 2020 onwards, things will move into the hot phase. The planning is in place, all the orders are out and the deliveries are arriving. The racks and cabinets will be assembled and the batteries installed in the supermarket's technical room by Helion, a business unit of Bouygues Energies & Services Switzerland.

The Italian company Ciemme Cablagi is responsible for the cabling and DC distribution of the large-scale storage facility. An inverter from the Zurich company indrivetec is used. Then the inverter goes to SmartOne in Germany for energy management programming. Finally, everything comes back and is also installed in the overall system, comparable to the wedding in vehicle construction when the engine is inserted into the chassis with millimetre precision - the most exciting moment in the birth of a car.

Commissioning and testing

Now the storage facility goes to the test site and is put through its paces. Different situations are simulated, programming is adapted, documentation is written. The final handover to the client MIGROS will take place in mid-February. Then the system should be maintenance-free and function optimally.

Conclusion and future prospects

It also works without lithium! It also works in an alternative, ecological and sustainable way. It works with regional and nearby value chains. It works with a standard of maximum safety. It works with a proven and yet new technology. It works with simple table salt. And not only with large-scale projects. innovenergy also has something to offer the homeowner with the smal salidomo© from 7 to 36 kWh. Likewise products in the medium capacity range such as the​​​​​​​ salimax© from 44 to 264 kWh. Or the​​​​​​​ salitrust©, a worthwhile offline UPS system for industry. The increasing demand shows that the concept of ecology and sustainability enjoys growing attention, meets the spirit of the times and is an important selection criterion among committed companies and private individuals.

New major projects have already been announced. One of them is with the contractual partner Helion. A threefold larger salt battery storage of 1.5 MWh is in the project planning stage. Both companies are hoping for a breakthrough in the commercial and industrial sectors soon, guaranteeing greater sustainability and safety for all.

Technical data

PV output: 730 kWp
Storage capacity: 540 kWh (24 high-voltage batteries of 22 kWh each, 620 V - FZSoNick ST523)
Inverter capacity: 220 kVA (indrivetec FC 320)

(SvN) (Image sources: MigrosMagazin)