Mini-neighbourhood heating cooperative

“Actually, you only need every second heating system.”

Basel, a neighbourhood from the 1930s characterised by terraced houses filled with the charm of yesteryear and the lives of their current residents. This is where Dominik Born lives. He is an Innovations Manager at IWB and spent seven years wondering why heating systems were not interconnected. Heatpooling instead of carpooling. Together with both of his neighbours, he has now started a nano-cooperative pilot project. “Actually, you only need every second heating system,” says Dominik with a provocative wink. The pilot project in his home proves it: during the previous winter, his geothermal heat pump also provided heat for both his neighbours’ homes. They saved around 15% of the costs during the first winter, using 90% renewable energy; the neighbours’ natural gas-fired heating systems supplied merely the remaining 10% of the energy required, which covered domestic hot water only.

Optimal use thanks to the nano-cooperative

The idea itself suggests that the Born family's heat pump system is oversized. But closer inspection revealed why Born was able to used his heat pump to heat three residential units instead of one: a heating system guarantees that requisite heating energy will be provided up to a certain temperature point. The size of Dominik’s Optiheat geothermal heat pump from CTA means that, at an ambient temperature as low as -8 degrees Celsius, it can provide enough power to make the house nice and cosy. You can count on one hand the number of days that it gets that cold in Basel, and this is where the nano-cooperative comes into its own: what the heat pump can do, it now does as well. Instead of fossil fuels, geothermal energy is now used to heat the neighbouring houses as well as his own.

The nano-cooperative

In a nano-cooperative, the existing heating systems are interconnected such that the most environmentally friendly heating systems (e.g. heat pumps) are always in use. This way, homeowners in the nano-cooperative heat their homes not only sustainably, but also cost-effectively. Instead of installing a separate heating system in each home, fewer heat sources are required, which in turn reduces investment and operating costs. “In densely developed areas, like here in this terraced neighbourhood, the nano-cooperative is a really exciting solution,” says Andreas Weber from Heizwert AG. For the past three years, he has helped to develop, install and optimise the nano-cooperative. For him, it is all about one thing: transitioning to renewable forms of energy. He is actively using his specialist knowledge to shape the future of energy in the field of building technology: “Those who don't yet need to replace their oil- and gas-fired heating systems can still contribute to the energy transition today.” Incidentally, it is unsure whether heating systems will need to be replaced at all: the case of Dominik and his neighbours has shown that one of the two gas-fired heating systems did not need to be replaced. Enough energy is from the Born family's heat pump to cover the majority of the heating, and it only needs supplementing when temperatures are low.

The fear of dependence

“A nano-cooperative also involves trust,” Dominik Born points out. He understands that home owners may be worried about being dependent on their neighbours' heating system. “With a heating cooperative, you also give up a little control,” he adds. If you don't want to make arrangements with your neighbours for the billing, a debt collection agency can handle it. This is the approach adopted for photovoltaic systems in ‘combination for users' own consumption’ systems.

Durable heat pumps

In conversations with speaking with interested home owners, Andreas Weber is always asked whether heat pumps in these systems have a shorter service life due to their increased use. “The opposite is true: increased use means fewer power cycles, which is good for the heat pump and minimises wear and tear.” Another advantage is the redundancy in the system: if one heating system breaks, the other heating systems in the cooperative take over until the fault is repaired. This ensures additional safety and reliability during heating operations.

Contributors

• Initiator and homeowner: Industrielle Werke Basel IWB, Dominik Born

• Joint development and installation: Heizwert AG, Muttenz

• Heat pump supplier: CTA AG, Münsingen