Mitsubishi Heavy Industries Provides 90kW CO₂ Heat Pump System for Adagio Hotel in London

Mitsubishi Heavy Industries (MHI) has installed a 90kW (25.5TR) CO₂ (R744) air-source heat pump to provide domestic hot water for an Adagio Hotel location in London.

The newly built hotel is in London’s Whitechapel neighborhood and comprises 140 units. In addition to meeting the demand of guests, the hotel’s hot water system had to meet local regulations around carbon and NOx emissions along with Adagio’s own sustainability goals, which is why MHI’s CO₂ heat pumps were chosen.

Where it gets technical: The system comprises three MHI Q-ton ESA30EH-25 units, configured as one master and two slave units.

• It’s paired with five 1,000L (264 gallons) storage tanks and supplies water at 75°C (167°F).
• Q-ton can operate in temperatures as low as −25°C (−13°F), while maintaining 100% heating capacity down to −7°C (19°F), according to MHI.
• The system is designed for integration with the building management system through Modbus, enabling the hot water plant to be monitored and controlled alongside other building services.

CO₂ for your stay: Adagio is not the only hotel company turning to CO₂ heat pumps.

• China-based Foshan LYD Energy Saving Technology has been installing CO₂ heat pumps in hotels since 2015. In 2024 LYD installed four water-source CO₂ heat pumps in a hotel in Macau to provide domestic hot water and space heating and cooling. 
• In September 2025 a CO₂ heat pump-chiller system was installed in an 87-room hotel in Goa, India, where it provides domestic hot water and air-conditioning. The system has a heating capacity of roughly 152kW (43.2TR) and produces hot water at 80°C (176°F) and a cooling capacity of roughly 110kW (31.3TR).
• In May 2025, a Mercure hotel in Melbourne, Australia, reported that it reduced its energy use for hot water by replacing two of its gas boilers with two 70kW (19.9TR) CO₂ heat pumps from Japanese manufacturer Itomic. The upgrade reduced hot water operating costs by 51%.

Heating up the U.K.: CO₂ heat pumps are finding their way into other projects across the U.K.

• In November 2025 a leisure center in Northern England replaced its gas boilers and combined heat and power plant with five CO₂ heat pumps, which provide a total of 1.5MW (426TR) of heating and deliver temperatures of up to 70°C for space heating, domestic hot water and the facility’s two swimming pools.
• Two air-sourced CO₂ heat pumps from Fenagy with a total capacity of 3MW (853TR) were at the center of a project to decarbonize London’s Clapham Park district heating network in 2025.

Quotable: “The Q-ton was chosen as it was the ideal solution to allow us to meet the ‘no local NOx emissions’ requirement of the London Plan and also significantly helping towards meeting our carbon reduction requirements for BREEAM [Building Research Establishment Environmental Assessment Method] and the London Plan requirements,” said Mick Matthews, M&E consultant at DMS, an HVAC contractor that worked on the project.