www.heatingandventilating.net


COMMERCIAL HEATING


Gas absorption - the alternative heat pump technology


Pure Thermal operations director Garry Broadbent explains the advantages of commercial gas absorption heat pumps (GAHP) in the context of decarbonisation targets


However, it’s clear that the situation can be viewed diff erently where gas absorption heat pumps are able to provide a transitional heat pump opportunity with electrifi cation to follow. This means that lower capital cost carbon


Above: A Plus- Gas Absorption Heat Pump providing Heating only


G


AHPs were widely applied throughout the UK from Robur up until 2014 with hundreds of units successfully operating nationally.


However, during the period where the electrifi cation of heat and fuel switching from gas became the industry priority Robur Gas Heat Pumps left the UK due to the increasing focus on electrically powered heat pumps and direct electric forms of heating. But now the need for more transitional measures


to accelerate carbon reduction has become apparent. The application of commercial gas absorption heat pumps has re-emerged with the potential to provide immediate carbon savings by simply reducing gas usage. These savings are achieved via heat pump technology, but without the need for increased electrical supplies. Consider that upgrading electrical supplies for


retrofi t commercial heat pump applications is costly and can be diffi cult to obtain due to regional or local electricity supply issues. We have 25 years until 2050 and it’s clear that a


more transitional approach, rather than immediate fuel switching from gas, can really benefi t some carbon reduction focused applications. We would ask if GAHP technology has been overlooked, in favour of electric heat pumps, because gas is seen as something that must be removed rather than gas usage being reduced.


reduction measures can be applied immediately via GAHP and long delays/costs for new electrical supplies can be avoided. So, what are the benefi ts of gas absorption heat pumps and why should they be considered? GAHPs are relatively straightforward to apply


as they use the incumbent/existing gas supply and use only 1 kW electricity to generate 40kW of heat. Consider that we have a commercial gas heater which is more than 100% effi cient off ering an immediate reduction in gas usage when compared to boilers. Taking the mantra of using less gas rather no gas, the application of GAHPs can make real sense for applications that do not have cost eff ective or timely access to increase electrical supplies in order to install electrically powered heat pumps. Considering the Robur GAHP track record, the question of proven technology is answered by there being hundreds of gas absorption heat pumps operating in the UK having been widely applied since 2004.


A modular approach is taken to GAHP


specifi cation utilising the Robur A-Plus 40kW unit in single or parallel unit confi guration. There is also the option to specify factory assembled skids with multiple GAHP units mounted in a single system plus there is also the additional option to select a hybrid system with heat pumps and skid mounted externally located boilers. This option provides a complete hybrid solution


by sizing the gas heat pumps to cover the maximum amount of carbon reductions and only bringing the Gas Boiler into play below an external temperature of say 5°C in order to provide additional capacity support. With respect to current UK demands, the


Above: AR Plus - Gas Absorption Heat Pump providing Heating or cooling


application team at Pure Thermal are confi dent that the confi guration options and case studies within both the UK and throughout Europe will be able to demonstrate correct GAHP application methods to provide confi dence to specifi ers and designers. It must be considered that this is not new technology, on the contrary this is extremely well- established technology with successful application going back over the last 20 years with GAHP simply being a diff erent type of heat pump refrigeration system to the vapour compression refrigeration system found in an electric heat pump.


How do they work, GAHP units utilise a burner to


place heat into the refrigeration circuit unlike the electrical compressor which does the same job in a vapour compression system, however, both types utilise air source or ground/water source renewable energy.


In summary GAHP units use gas to generate heat


using renewable source energy, be it air or water, to provide a system that will use circa 40% less gas than the incumbent boiler. Hence, we have a heat pump system which is


practical and easy to apply & integrate with existing gas supplies with an output temperature capability of 70°C. The present unknown situation regarding the use of the gas in the future is still to be determined with a consultation concerning the Gas Transition launched in November 2025. However, when considering the use of gas, it is noted that in Q4 of 2025 a signifi cant investment of circa £150 million was placed by Government into making ready certain sections of the grid to take advantage of hydrogen to a mix of 5%. Alongside this it should also be noted that Biogas is gaining more momentum as is also the case in Spain and Italy with the objective of supplying the grid with clean renewable gas. In summary this indicates that the application of gas absorption heat pumps can be viewed as an immediate transitional carbon reducing technology for the next 15 years until remedial improvements to the electricity grid ensure that power is more readily available to apply electric heat pumps. Or importantly it can be considered that GAHP


may be a technology that could be viewed as long term to operate for many years with a gas grid circulating clean gas that could be a mix with a biomethane or hydrogen base. But whichever view is taken, whether transition or long term, there is no doubt that Gas Absorption Heat Pump technology is proven and ready to be applied now for both new or retrofi t applications.


DOWNLOAD THE HVR APP NOW June 2026 15


7 x 40kW Gas Absorption Heat Pump units roof located


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32