Gas driven heat pump technologies can be split into sorption heat pumps and gas engine driven heat pumps. Efficient, gas driven heat pumps can reach high temperatures and therefore be used with existing distribution systems especially fit to produce domestic hot water in collective open systems. An important advantage of Gas driven heat pumps is the lower load on the ground source system as less heat is extracted from the source.
In November 2019 the Industry White Paper The Gas Heat Pump and Technology Road Map, was published by the US Gas Technology Institute and BRIO. This white paper outlines the road ahead for Nothern America and it identifies opportunities, information gaps, impediments and strategies to accelerate the commercialization and market acceptance of gas heat pumps (GHPs) in North America including Canada. GTI very active in this field focuses on cold climate applications, where they have had a number of monitored projects, and develop into best practices guidelines. One of these is Gas Engine-driven Heat Pump (GHP) Cold Climate Field Demonstration Variable Refrigerant Flow (VRF) Heat Pump Systems in Cold Climates. A number of projects have been monitored.
Absorption Heat Pumps
The market for the gas absorption heat pumps in the built environment in Europe nowadays is relatively small nominated by one manufacturer (Robur, also sold as Buderus, Xinoé, and Remeha), although there is a number of interesting projects especially in France. In the USA and Canada a number of projects have been identified. A special project is the renovation of a number of old residential block of flats, the Benny Farm in the quarter of Notre Dame de Grâce in Montréal. The metamorphosis of Benny Farm, at Notre-Dame-de-Grâce, was ambitious an extensively described in the report Community Inspired Housing in Canada.
United States –Park Forest a multifamily house in Jackson Michigan (United States) has an interesting combination of 18 ROBUR absorption air source heat pumps providing space heating and domestic hot water by individual risers in wintertime and 4 ROBUR gas fired chillers in summertime to provide domestic hot water from what is called waste heat from cooling.
Gas Engine Heat Pumps
Gas engine driven heat pumps (GHP) currently hold a small share of the U.S. and European HVAC market. This share is considerably smaller than what the full potential of GHP technology can realize. Two well-known gas engine driven heat pump manufacturers are Aisin-Toyota and Sanyo. There is also a Dutch company that produces gas engine driven heat pumps. The company is called Reduses and it produces gas engine heat pumps of reasonable sizes.
A study published as ‘Natural Gas Internal Combustion Engine Heat Pump Field Trial’ describes the pilot with a Tecogen-Ilios gas engine heat pump with a rated capacity of 117 – 175 kW fired with propane. The Capital Manor Retirement Community in Salem, OR was selected as an ideal site with a large DHW load, significant DHW storage capacity and reasonable installation logistics.
New is boostHeat, a gas fired combination of a standard condensing heating unit with a CO2 heat pump cycle driven by thermal compression. It sums up to a condensing heating unit supplying 20 kW heat at 65oC and a PER of up to 200. The development in France was started in 2004 and supported by strong partners holding stakes in the gas sector.
The European project on ‘Sun coupled innovative Heat pumps’, reports the baseline and boundary conditions of SunHorizon demo sites, including a number of monitoring aspects.