Alpiq and Pflugshaupt Engineering AG have developed a concept for the emergency power supply of the Gossau sewage and purification plant on behalf of Energie Gossau AG (ZH). A sustainable battery storage unit, which offers extensive energy management, is being used in place of the old diesel generators. To this end, the emergency power distribution system has been completely reengineered. It now not only supplies the ARA Gossau plants; the design also allows third parties to be supplied with emergency power and opens Energie Gossau AG up to entirely new service concepts as an operator.
The almost 10 tonne battery storage unit with a capacity of 300 kW has been seamlessly integrated into the existing building. The storage unit enables data to be exchanged with the ARA control system, the combined heat and power plant (CHP), the gas tank, the photovoltaic system and various circuit breakers and measuring devices. Messages about the status, faults and the current output are automatically sent to the storage unit and the plants are thus integrated into the emergency power supply. Conversely, the storage unit sends signals about its status and can control the connected plants in stages.
“What is special about the project is that we have not only been able to supply emergency power to our customer, i.e. the sewage treatment plant, but have also been able to include the existing production facilities, the combined heat and power plant and the photovoltaic systems. This is something new for our industry,” says Martin Pflugshaupt, Managing Director of Energie Gossau AG, who is primarily responsible for the concept and project management.
Power: 300 kW, also in emergency power mode
Capacity: 384 kWh
Number of modules installed: 20
Battery type: Lithium iron phosphate (LiFePO4)
Use: Emergency power supply, peak-shaving, flexibility marketing
Weights and measures: 10 tonnes
Alpiq’s battery storage system not only guarantees the supply of emergency power to all the important processes, it also enables load management. In emergency mode, the CHP and the PV system are switched on as support and thus enable an off-grid power supply that can last from several hours to days. If there is still no grid available after more than a day, the supply can be supported by a mobile unit. “This enables us to achieve a stable power supply in any situation,” says Roger Burkhart, Senior Business Developer Storage Solutions and Project Manager at Alpiq. In the future, the system will also be used to reduce load peaks and even to provide system services.
At present, the storage system supplies five emergency power outlets and has additional capacity. “It’s an ingenious and exciting project! It is always great to see how such a comprehensive concept is developed and implemented from an initial idea,” says Roger Burkhart, summing up.
Large battery storage units are used successfully for many applications around the world – including in Switzerland – and are an important part of the new energy system. Learn first-hand from practice-oriented experts what’s important in terms of business model development, planning, integration and operation.