Heat pumps can save money and lessen environmental impact for heating and cooling systems when applied appropriately. Their applications are diverse, covering office air conditioning, domestic heating and industrial processes.
About 96% of all heat pumps sold in the UK are for non-domestic buildings - over 60,000 units in 1996 alone. Sports centres, particularly those having swimming pools, are ideal candidates, where the heat pump can provide both heating and dehumidification. Retail outlets and office buildings where there is a need for simultaneous heating in one area and cooling in another can benefit from substantial energy cost savings. Unfortunately, many users with reversible heat pumps (i.e. capable of Winter heating and Summer cooling) only use them for cooling. So in winter they pay to run a boiler, when the heat pump could meet some or all of the demand - a missed opportunity to save money and environmental impact.
The increased use
of 'low energy' building design, natural ventilation and/or passive cooling
will affect the commercial market: Smaller heating/cooling plant needs and the
reduced cost of smaller heat pump installations may accelerate the take-up of
reversible units in these situations.
See
GIL024 All Electric Air-conditioned Offices uses Heat Pump Technology.
Industrial heat pumps are used to recover or make best use of heat in manufacturing processes or in public utilities such as energy generation & distribution. They vary enormously in both size and concept, but most are specially designed for the application. In the UK the best seller is the dehumidifier/dryer for batch drying ovens, e.g. for textiles or wood, where duties of a few kW are typical. In Japan, Sweden and the Netherlands, multi-MW heat transformers operating on the absorption cycle are used for waste heat recovery in petrochemical and steel works.
While the potential
for industrial heat pumps in the UK is substantial and largely un-exploited,
success in the food and drink sector with mechanical vapour recompression (MVR)
systems continues, and larger units could be cost-effective in chemical distillation
plant.
See
GIL068 Industrial heat pumps. Benefits and experience in the chemicals, food
and drink, ceramics and other sectors.
and
GPCS268 Rapid Drying with a Heat Pump Dehumidification System.
Heat pumps are a feature of many homes in, for example, Switzerland, Norway and the Netherlands, but not many systems have been installed in the UK.
The UK market is strongly influenced by first cost for heating systems, and gas heating is fairly cheap, widely available and fairly clean. Apart from some purpose-built demonstration houses, domestic heat pumps in the UK tend to be confined to rural areas without gas supplies. In these areas oil is the main alternative which is currently very economical. Domestic heating only heat pumps can compete environmentally and economically with gas heating. Reversible heat pumps, which can also provide summer cooling, are not as efficient as those designed for heating only and are likely to result in higher heating bills and overall greater environmental impact compared to other fuels. The output of currently available domestic heat pumps is limited to approximately 5 kW so they are best suited to small or very well insulated properties.
Heat Pumps in the UK - a monitoring report
This Report summarises the findings of a project to evaluate the energy and environmental performance of heat pumps in the UK climate. The project involved installing a ground source heat pump in a domestic house and monitoring its performance over the first year of operation.
The heat pump is used to supply an under floor heating system in a large, but well-insulated, private dwelling. The heat pump maintains satisfactory comfort conditions and no significant problems have been encountered. The heat pump has achieved an overall coefficient of performance (CoP) of 3.16, although scope for further improvements have been identified.
The limitations of the study means that these figures cannot necessarily be applied to other types of heat pump or situations, and their energy and environmental performance should be carefully evaluated on a project by project basis. In particular, CoPs for heat pumps capable of providing cooling may be significantly lower and result in higher running costs and higher CO 2 emissions.
Click
to download "Heat Pumps in the UK - A monitoring report"
See also
GIR067 Heat pumps in the UK: Current Status and activities
GIR070 HEat Pump and Heat Pump-Related R&D in UK Universities
The applications section of the website is designed so that we can provide information about systems and equipment appropriate for industrial, commercial or domestic requirements. If you want to submit a case study contact the secretariat.
Successful examples
can be found at http://www.caddet-ee.org
and then search for heat pumps.
The IEA Heat Pump Centre has recently published a new collection of domestic
case studies "Ground-Source Heat Pump Systems Case Studies" ref. HPC
- AR10, http://www.heatpumpcentre.org
UK
Heat Pump Network, BRE Sustainable Energy Centre (BRESEC), Garston, Watford,
WD25 9XX
Tel: 01923 664500, Fax: 01923 664087, e-mail: secretariat@heatpumpnet.org.uk