This area is for the GSHP (Ground Source Heat Pump) Information with regards to the village hall system.
The Ground Source Heat pump consists of 25mm PE pipe buried approx 2 metres below ground covering an area of 650 square meters. This in turn is connected to a manifold which brings all the pipework together before connection to the flow and return pipe, which is 50mm Poly Pipe MDPE. The flow and return are in separate trenches leading to the plant room. In the Plant room we have two Cylinders, one is a hot water tank and the other a buffer tank. Also in the Plant Room are the 2 x Geotherm 8 Heat Pumps. The Heat Pumps compress the incoming solution which heats it further before it is circulated around the building which will have new electric fan assisted radiators. My understanding is that these are very efficient and that for every unit of energy put in they produce 4 units of energy by way of heat.
They are now ins the process of being installed (January 29th 2011)
GSHP (Ground Source Heat Pump)
A geothermal heat pump or ground source heat pump (GSHP) is a central heating and/or cooling system that pumps heat to or from the ground. It uses the earth as a heat source (in the winter) or a heat sink (in the summer). This design takes advantage of the moderate temperatures in the ground to boost efficiency and reduce the operational costs of heating and cooling systems, and may be combined with solar heating to form a geosolar system with even greater efficiency. Geothermal heat pumps are also known by a variety of other names, including geoexchange, earth-coupled, earth energy or water-source heat pumps. The engineering and scientific communities prefer the terms “geoexchange” or “ground source heat pumps” to avoid confusion with traditional geothermal power, which uses a high temperature heat source to generate electricity. Ground source heat pumps harvest a combination of geothermal energy (from the earth’s core) and solar energy (heat absorbed at the earth’s surface) when heating, but work against these heat sources when used for air conditioning.
Depending on latitude, the upper 3 metres (9.8 ft) of Earth’s surface maintains a nearly constant temperature between 10 and 16 °C (50 and 60 °F). Like a refrigerator or air conditioner, these systems use a heat pump to force the transfer of heat from there. Heat pumps can transfer heat from a cool space to a warm space, against the natural direction of flow, or they can enhance the natural flow of heat from a warm area to a cool one. The core of the heat pump is a loop of refrigerant pumped through a vapor-compression refrigeration cycle that moves heat. Heat pumps are always more efficient at heating than pure electric heaters, even when extracting heat from cold winter air.. But unlike an air-source heat pump, which transfers heat to or from the outside air, a ground source heat pump exchanges heat with the ground. This is much more energy-efficient because underground temperatures are more stable than air temperatures through the year. Seasonal variations drop off with depth and disappear below seven meters due to thermal inertia.Like a cave, the shallow ground temperature is warmer than the air above during the winter and cooler than the air in the summer. A ground source heat pump extracts ground heat in the winter (for heating) and transfers heat back into the ground in the summer (for cooling). Some systems are designed to operate in one mode only, heating or cooling, depending on climate.
The geothermal pump systems reach fairly high Coefficient of performance (CoP), 3-6, on the coldest of winter nights, compared to 1.75-2.5 for air-source heat pumps on cool days. Ground source heat pumps (GSHPs) are among the most energy efficient technologies for providing HVAC and water heating. Actual CoP of a geothermal system which includes the power required to circulate the fluid through the underground tubes can be lower than 2.5. The setup costs are higher than for conventional systems, but the difference is usually returned in energy savings in 3 to 10 years. System life is estimated at 25 years for inside components and 50+ years for the ground loop. As of 2004, there are over a million units installed worldwide providing 12 GW of thermal capacity, with an annual growth rate of 10%.