Whilst ground source heating is a highly efficient way to provide renewable energy to new buildings and for retrofitting of well insulated existing buildings, ground source heating systems often receive a bad press. There are four main reasons for this:
- Ground source heating systems need to be operated in a different way to traditional high temperature alternatives such as gas and oil. Ground source systems produce low temperature heat to the building, ideal for buildings with under floor heating. They are not so efficient when the heat is transferred to the building using radiators, especially if the building is poorly insulated or where windows or doors are regularly left open. In these circumstances the heat into the building cannot keep pace with the heat escaping from it.
- Ground source systems are often designed and installed by companies that have no or limited knowledge of the ground. The result can be that unsustainable systems are installed. Systems often produce sufficient heat in the early stages until the heat resource in the ground becomes depleted. Thereafter supplementary heat is required to make up the heat deficit. This can prove costly, especially if the supplementary heat is provided by immersion heaters.
- Air locks can occur in the ground collectors (the underground pipework which absorbs the heat from the ground) preventing flow of collector fluid through whole sections of pipework, which can considerably reduce the efficiency of a ground source heating system).
- Plant room issues can prevent systems from working to their full potential, from incorrect sizing of heat pumps to incorrect installation of system components to functional problems with the heat pump.
OGI’s design and installation experience of often complex and large scale commercial ground source heat pump installations means that OGI is perfectly placed to identify the cause of failing systems and to recommend and design remedial solutions.
OGI have carried out trouble shooting works for education authorities, local government, health authorities, care homes as well as private individuals.
In this example a recently built Primary school in London had had a ground source heat pump installed by a company that went out of business prior to system handover.
Issues were identified by OGI including air trapped in the ground loops, insufficient air vents and collector circuit filters, and incorrectly specified circulation pumps.
OGI remedied the problems enabling the system to operate to the Client’s original design specification for the first time.