What is GHP
A GHP outdoor unit is a variable speed direct expansion gas fuelled unit which is capable of producing heating or cooling and also produces hot water from cooling the engine.
GHP Outdoor Units with AHUs
Ideal for sites where cooling is required via central plant but there is just not enough electrical power there to operate a water chiller or direct expansion condensing units we can connect GHP outdoor units directly to the cooler coils in an air handling unit. Heating can either be by combustion or, much more efficiently, by changing the mode of the outdoor unit from cooling to heating.
GHP Hydronic Systems
For sites where traditionally a water chiller would have been used, Hydronic GHP is an ideal alternative. The GHP outdoor unit is connected to a Hydronic module to produce chilled or hot water which can then be distributed around the building and used as required.
GHP 2 pipe VRF System
A very efficient solution is to use a 2 pipe VRF system where multiple indoor units are connected by refrigeration pipe to a central outdoor unit. The system is in either cooling or heating mode but each indoor unit operates independently. Using gas to fuel the compressors means minimal power consumption unlike a conventional electric VRF alternative. This can be reduced even more by a Power GHP system which uses an alternator to generate the electricity required by the indoor units.
GHP 3 pipe heat recovery VRF system
Utilising heat recovery to pump heat from one part of the building where it is not required to part of the building where it is, a 3 pipe GHP VRF system combines minimal electrical power consumption with maximum efficiency and has the added comfort benefit of allowing simultaneous heating and cooling all powered by gas.
Hybrid GHP System
A hybrid GHP uses a combination of VRF direct expansion indoor units or air handling units plus a water heat exchanger to create a reservoir of either chilled or hot water or even both.
Gas Engine versus Gas Absorption
The technology we use in GHP technology is called 'Gas Engine' because it uses a conventional vapour compression cycle but powered by a gas engine rather than an electrical motor.
This should not be confused with Gas Absorption refrigeration which uses a vapour absorption cycle instead. Gas absorption chillers are different and have advantages and disadvantages. One of the bigger advantages of GHP systems over absorption is the very fast reaction time of GHP which is easy to turn on and off and respond to changes in demand.
For more information on both vapour compression and vapour absorption cycles read this article.