Energy and carbon-emission solution at our feet
Calorex Ground Source Heat Pumps can extract around 75% of their usable heating energy from the ground and can generally reduce carbon emissions compared to gas central heating systems by about 50%. Installed as the sole source of heating and hot water, they will reduce carbon-dioxide emissions from a dwelling to zero.
Tony Barnes believes the British are hot on the heels of ground-source heat-pump technology.With unprecedented increases in UK energy costs in recent years and with 2006 having seen some of the biggest rises in history, energy efficiency and economy is on every agenda.
— With no maintenance costs and low fuel costs, ground-source heat pumps provide the ideal solution to local authority demands for renewable energy restrictions on new planning applications. These figures are for a new-build project of 100 m2 and are based on September 2006 fuel prices.
With this in mind, the UK market is finally warming up to the win, win appeal of heat-pump technology — hot on the heels of a huge number of heat-pump installations in countries such as Sweden, Switzerland, France, Germany and the USA. Heat pumps provide a significant hedge against these consistent increases and volatile spikes in oil and gas prices. In fact the only running cost to account for is electricity. With almost 75% of the usable energy being drawn from the ground for a ground-source heating system, this means that for every 4 kW of power required in the home only 1 kW is required to run the heat pump. This gives the heat pump a rated efficiency of 400% for space heating.
— With 30% of all UK carbon emissions coming from the 24 million dwellings in the UK there are many opportunities to install ground-source heat pumps to help reduce these emissions.
In addition, there are no annual maintenance or service checks to budget for as, unlike a gas heating system, they are not required. The public-sector housing provider can realise considerable additional savings depending on the number of properties in which heat pumps are installed. Many local authorities now insist on the provision of renewable energy as a condition of planning permission for new-build projects. Ground-source heat pumps can often assist the developer meet these provisions.
Environmentally friendly Ground-source heat pumps maximise the freely available solar energy that is available everywhere in the UK —energy that is totally renewable and sustainable. For example, a Calorex ground-source heat pump installed in a home as the sole source of heating and hot water will reduce carbon-dioxide emissions from the dwelling to zero. Traditional fossil-fuel reserves in the UK such as oil and gas are fast becoming exhausted, and the DTI estimates that these finite deposits could expire totally by around 2016. When fossil fuels are burnt to produce energy, carbon dioxide is released into the atmosphere, which in turn adds significantly to the global concerns over climate change. Ground-source heat pumps can extract around 75% of usable heating energy from the ground and can generally reduce carbon emissions compared to gas central heating systems by approximately 50% For properties which are off the gas network and where a heat pump is installed, carbon-dioxide savings are even greater than 50% when compared to those emissions produced by oil, LPG, electric space heating and solid fuel. As there are no emissions from systems, no flues or condensate drains are required, and there is no pluming or local pollution from the installation property. The cumbersome inconvenience and cost of fuel storage as with oil, LPG and solid fuel is also removed.
New build and refurbishment With 30% of all UK carbon emissions coming from the 24 million dwellings in the UK, there are many opportunities to install ground-source heat pumps to help reduce these emissions. Following the Energy White Paper of 2003 the UK Government provided legislation to: • raise building energy efficiency standards; • raise boiler efficiency standards; • update Part L of the Building Regulations (2002); • Improve correlation between building design standards and actual performance. As a result, ground-source heat pumps are now recognised by the Government’s Standard Assessment Procedure (SAP) and show significant carbon savings over other forms of space and water heating.
Installation characteristics The installation of ground-source heat pumps and the design of heating system designs should be carefully integrated to optimise efficiency and performance. The characteristics of every installation require that all parts of the system are designed around the following principles. • Building: consideration of the thermal characteristics of the property and end-user requirements for space heating and domestic hot water.
• Heat Pump: output matched to the requirements of the building.
• Ground loop: designed to provide renewable and sustainable energy in line with the requirements of the building load and heat pump. An appropriately designed system should see a ground-source heat pump have an efficient lifetime of around 25 years, with the ground loop having an expected life of around 100 years.
Tony Barnes is the sales director of the domestic heating division of Calorex Heat Pumps Ltd.
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