Johnson Controls to supply Zürich with heat pumps using waste energy
CORK, Ireland, 2 September 2025: Johnson Controls said it will be providing green heat to the city of Zürich through a new waste incineration project spearheaded by the municipal utilities of Zürich ERZ (Entsorgung & Recycling Zurich). Making the announcement through a Press Release, Johnson Controls said the project entails the expansion of the plant with a third process line and heat recovery from the flue gases.
As part of the project, Johnson Controls said its heat pumps feed the recovered energy into the District Heating network and provide additional heat to around 15,000 homes. Starting operations in 2027, the company added, the solution is one of the largest in Europe to use ammonia, which has zero Global Warming Potential (GWP), in a heat pump application on this scale.
According to the European Heat Pump Association, heat accounts for more than 60% of energy use in European industries, and there is significant potential to meet this need using freely available ambient or waste heat sources – estimates suggest that waste heat in the EU could meet the bloc’s entire energy demands for central heating and hot water. Heat pumps can harvest this energy from land, water, air or industrial processes and are typically 3-4 times more efficient than conventional systems, Johnson Controls said.
Richard Lek, President, Johnson Controls, EMEA, said: “As one of the largest untapped sources of energy, excess heat represents huge potential for businesses to reduce operating costs and become more resilient while meeting decarbonization targets. In 2024 alone, Johnson Controls helped cut customers’ expenses by 53% and reduce emissions by 60% compared to conventional natural gas boilers. We are proud to be partnering with ERZ on this innovative project and highlight the tremendous opportunity of waste heat sources – paving the way toward more energy-efficient and sustainable urban environments.”
Johnson Controls said that for the city of Zürich, it will provide a custom-made heat pump solution with six high-performance screw compressors, delivering a total system output of 42 MW. The heat pumps will extract low-temperature heat from the flue gas of a large waste-to-energy facility – raising the overall efficiency of the plant significantly. Johnson Controls added that to maximise the waste heat extraction and further increase efficiency, the units will be applied as three pairs of heat pumps operating in series, reducing the lift required, and expected to boost efficiency by as much as 30%.
Furthermore, the company highlighted the operating conditions are ideal for the heat pumps, as they are positioned first in a combination of multiple heat sources that raises the temperature before being supplied back to the grid. This ensures the optimum overall efficiency of the plant.
Jürg Bruder, ER, said: “The City of Zürich is actively committed to achieve net carbon neutrality by 2040, and a major part of this is the increase of carbon free supply of heat. By teaming up with Johnson Controls, we are further driving momentum in the heat transition and paving the way toward a more sustainable future.”
Johnson Controls said it was among the first providers of heat pumps and that it now supplies a broad portfolio for commercial, institutional and industrial organisations. The company added that its industrial and commercial heat pumps are used in sectors ranging from manufacturing and healthcare to municipalities and utilities. Johnson Controls also said it is supporting the transition to more sustainable refrigerants by offering heat pumps that use low- and ultra-low-global-warming-potential fluids.