U.K.-based OEM Clade Engineering provided five propane (R290) air-to-water heat pumps with a total capacity of 900 kW (255.9TR) over the summer of 2022 to Northumbria University in Newcastle, U.K., as part of the retrofit and upgrade of two buildings.

The heat pumps provide heating for dozens of lecture halls, offices, cafes and other facilities within the buildings.

The university was motivated to reduce carbonization as part of its Environmental, Social and Governance (ESG) regulatory framework, and “natural refrigerants fitted that very well,” said Tim Rook, Chartered Engineer and Chief Markets Officer for Clade Engineering.

Rook described the development and installation of Clade’s natural refrigerant heat pumps at the November 2022 ATMOsphere (ATMO) Europe Summit in Brussels. He discussed two installation case studies and the use of a live COP calculation method. ATMO Europe was organized by ATMOsphere, publisher of Hydrocarbons21.com.

Using thermal modeling for verification, the heat pumps in the Northumbria buildings deliver a flow temperature of 60°C (140°F) with a return temperature of 40°C (104°F). To achieve this, “Clade changed the air handling unit coils, the valves, the pumps, and other stuff in the building system itself to make it work,” Rook said. As of the November 2022 summit, four of the heat pumps were up and working with an average COP of less than 4.0.

Energy services company EQUANS has supported Northumbria in the installation of the £1.7 million (US$2.1 million) Clade heating system, replacing gas boilers with the heat pumps, according to Northumbria. The project was funded mainly by the U.K.’s Public Sector Decarbonisation Scheme.

Clade has a live COP calculator capability, an effort to bring data acquisition to the HVAC sector. “After spending the last three years working with IBM, Industry 4.0, data analytics, artificial intelligence, and more, data acquisition is absolutely vital,” said Rook. “This will enable Clade to not only build better heat pumps and provide new services to customers but to also chase down those last 0.1% of the COPs.”

In addition, Clade’s data acquisition seeks to support the flexibility of the commercial non-public sector’s grid. “We are working with energy traders, intelligence providers and network operators with our digital platform, so they can provide flexible power services, keeping the lights on during high demand and the cost for carbon low,” said Rook.

In the second case study, a 200 kW (56.9TR)-capacity CO2 (R744) heat pump was installed to provide heat in a leisure center with a swimming pool.

46 NatRef heat pumps in the past year

In its past fiscal year, Clade installed or shipped 46 natural refrigerant heat pumps, totaling 10.85MW (3,085TR) of heating capacity in the U.K. market, said Rook. The heat pumps range in size from 50 to 1 MW (14.2 to 284TR) and equipped with live COP calculation capabilities. Clade has over 500 natural refrigerant appliances installed in the market, he added.

Most of Clade’s 30-year history has been spent in a “natural refrigeration journey,” said Rook, though it developed its natural refrigerant heat pumps in the last four years. Clade’s heat pumps use propane, isobutane (R600a) or CO2 natural refrigerants. Rook reported that the HVAC sector in the U.K. has “finally” turned to heat pumps, “but there is a lack of skills in both manufacturing and applications of heat pumps.”

According to Rook, Clade seeks to learn from the heat pump market in the U.K.. “Noise, for example, is becoming quite a big issue for air-source heat pumps,” said Rook, “So we’ve developed a model which reaches very low noise levels even in full-out mode.”

Headquartered in Bristol, U.K., Clade manufactures its heat pumps in Leeds.

“We’ve developed a model which reaches very low noise levels even in full-out mode.”

Tim Rook, Chartered Engineer and Chief Markets Officer for Clade Engineering