During the conference dinner at the 15th IEA Heat Pump Conference in Vienna, Austria, five distinguished professionals were presented with the Peter Ritter von Rittinger International Heat Pump Award 2026, the highest international honour in the heat pump, air conditioning and refrigeration sector.
The 2026 awardees are Prof. Graeme G. Maidment, London South Bank University; Thomas Nowak, Vice President Government Relations and Public Affairs, Qvantum International; Prof. Renato Lazzarin, Emeritus Professor at the University of Padua, Italy; Prof. Björn Palm, KTH Royal Institute of Technology, Sweden; and Dr. Choyu Watanabe, Executive Officer, Zeneral Heatpump Industry Co., Ltd. and Nagoya University.
The award recognises outstanding contributions to international collaboration in research, policy, market development and applications of energy-efficient heat pumping technologies that strengthen energy resilience and deliver environmental benefits. Presented every three years in connection with the International IEA Heat Pump Conference, it was handed over by Stephan Renz, Chair of the Executive Committee of the Technology Collaboration Programme on Heat Pumping Technologies (HPT TCP) under the International Energy Agency.
“It is my great pleasure to recognize these dignified nominees and honour them with the most prestigious prize in the field of heat pumping technologies,” said Mr. Stephan Renz during the ceremony. “Our award winners are undoubtedly some of the most influential individuals in the history of HPT TCP by IEA.”
Prof. Graeme G. Maidment, London South Bank University
Graeme Maidment has made internationally recognised contributions to heat pumping technologies over four decades. His career began as an apprentice at J&E Hall in 1983 and has since spanned academic, industrial and governmental leadership. He is Professor of Heating and Cooling at London South Bank University and holds an advisory role at the UK Department for Energy Security and Net Zero, helping shape national decarbonisation strategy. He co-leads the global Mission Innovation Affordable Heating and Cooling initiative and is a key figure in the UNEP-led Cool Coalition.
Maidment has led or co-led more than 40 major research and demonstration projects worth over GBP 15 million, advancing heat pump applications from supermarkets and data centres to rail infrastructure and district heating. His work on fifth-generation ambient-loop district heating and cooling, exemplified by the GreenSCIES project in London, has become a global reference for smart, low-temperature heat networks. His work on recovering waste heat from the London Underground earned the Rail Business Award and has been cited in UK Research Excellence Framework impact case studies. With more than 100 peer-reviewed publications, he has served as President of the Institute of Refrigeration, and his awards include the J&E Hall Gold Medal and the RAC Journal Gold Award. Prof. Graeme G. Maidment was awarded for great contributions in technology advancement and administration.
Thomas Nowak, Qvantum International
Thomas Nowak, Vice President Government Relations and Public Affairs at Qvantum International and former Secretary-General of the European Heat Pump Association, spent 17 years as the driving force behind EHPA, the voice of the European heat pump sector in Brussels. Under his leadership the association grew from a one-person organisation to a team of nearly 25 staff and more than 200 member organisations.
During this period European heat pump sales grew from 500,000 units annually to 3 million, with heat pumps now providing clean heating and cooling to nearly 16 percent of Europe’s buildings. Nowak connected the sector to policymakers at European and international levels through advocacy, communications and certification work, establishing heat pumps as critical to decarbonising buildings and industry and to securing Europe’s energy independence. Tomas Nowak was awarded for great contribution in market development.
Prof. Renato Lazzarin, University of Padua
Renato Lazzarin has built a career spanning some 40 years of pioneering research in heat pumping technologies. Holding degrees in Mechanical Engineering and in Statistical and Economic Sciences, he was Full Professor of Applied Physics and Thermodynamics at Padua from 1986 until attaining Emeritus status in 2022. His publication record exceeds 400 works in international and national journals and conference proceedings, alongside 18 books on heat pumps, energy conservation, renewable energy and air conditioning.
His early research in solar-assisted heat pumps and in open and closed cycle absorption systems produced papers now regarded as pioneering in the field. He subsequently developed multi-source heat pump systems, dual-source configurations and the integration of phase change materials in solar heating and cooling. He served as Chair of IIR Commission E1 on Air Conditioning from 2011 to 2019 and has been President of IIR Section E since 2019. He organised major international conferences, including the IIR International Sorption Heat Pump Conference in Padua in 2011, and was President of the Italian Association of Air Conditioning, Heating and Refrigeration from 2008 to 2010. Prof. Renato Lazzarin was awarded for great contributions in technology advancement.
Prof. Björn Palm, KTH Royal Institute of Technology
Björn Palm brings more than 40 years of scientific research in applied thermodynamics, heat transfer, refrigeration and heat pumping technologies. He has published over 200 scientific papers, peer-reviewed conference papers and scientific reports, generating approximately 9,000 citations, and has supervised more than 30 PhD and Teknologie Licentiate graduates, most of whom now work as refrigeration and heat pumping experts in industry and academia worldwide.
Palm served as Head of the Division of Applied Thermodynamics and Refrigeration at KTH for 24 years, retiring from that role in 2023, and as Head of the Department of Energy Technology from 2011 to 2017. His research on heat pumping systems for heating and cooling, natural refrigerants, heat transfer in boiling and condensation, microchannel heat exchangers, and nanofluids has been carried out in close collaboration with industry partners, primarily Swedish companies in the heating, cooling, and telecom sectors. He received the ASME Outstanding Researcher Award in 2011 and the IIR Science and Technology Medal in 2023. Prof. Björn Palm was awarded for his great contribution to technology advancement.
Dr. Choyu Watanabe, Zeneral Heatpump Industry Co., Ltd. and Nagoya University
Choyu Watanabe, Executive Officer at Zeneral Heatpump Industry and Visiting Professor at Nagoya University, has conducted research and development across the full spectrum of Japanese heat pump technology, from cryogenic refrigeration to high-temperature industrial heat pumps, and has played a significant role in introducing these technologies to the international community.
His technical contributions include CO2 supercritical high-temperature hot water production heat pumps reaching 90 degrees Celsius, 165 degree Celsius steam-generating heat pumps developed at the Central Research Institute of Electric Power Industry, and heat pumps for simultaneous cooling and heating in cutting and cleaning processes. He participated as a key member of IEA HPT TCP Annex 35 on Applications of Industrial Heat Pumps and Annex 48 on Industrial Heat Pumps, Second Phase, presenting Japan’s advanced technologies to experts across Europe and North America. He served as Vice Chair of the Advisory Committee of the 24th IIR International Congress of Refrigeration in Yokohama in 2015. Watanabe holds US, European, and Japanese patents and has received multiple awards from the Japan Society of Mechanical Engineers, the Japan Society of Refrigerating and Air-Conditioning Engineers, and the Japan Society of Heat Transfer. was awarded for great contributions in technology advancement and applications.
About the Peter Ritter von Rittinger International Heat Pump Award
The Rittinger Award is named after Peter Ritter von Rittinger, the Austrian engineer who designed and installed the first known heat pump in 1855. The award celebrates the technical skills and entrepreneurial spirit of Rittinger that is shared by the award winners.
Source: Based on the Heat Pump Centre press release, May 2026. For further information on the Peter Ritter von Rittinger International Heat Pump Award, contact the Heat Pump Centre at hpc@heatpumpcentre.org, or see https://heatpumpingtechnologies.org
