About Heat Pumps
Heat Pumps
Ground source heat pumps, also known as geothermal heat pumps, are used for space heating and cooling, as well as water heating. They operate on the fact that the earth beneath the surface remains at a constant temperature throughout the year, and that the ground acts as a heat source in winter and a heat sink in summer. They can be used in both residential and commercial or institutional buildings.
Ground
The earth’s surface acts as a huge solar collector, absorbing radiation from the sun. In this country the ground maintains a constant temperature between 11oC and 13oC, several metres below the surface. Geothermal Heat Pumps take advantage of this by transferring the heat stored in the earth or in ground water to buildings in winter and the opposite in summer for cooling. Through compression, heat pumps can ‘pump up’ heat at low temperature and release it at a higher temperature so that it may be used again. A heat pump looks similar and can perform the same functions as a conventional gas or oil boiler, i.e. space heating and sanitary hot water production. For every unit of electricity used to operate the heat pump, up to four units of heat are generated. Therefore for every unit of electricity used to pump the heat, 3-4 units of heat are produced.
Installation in the Home
The system has three main components: a series of pipes in the ground, a heat pump and a heat distribution system. Lengths of plastic pipes are buried in the ground, either in a borehole or a horizontal trench near the building to be heated or cooled. Fluid, normally water with anti-freeze, absorbs or emits heat to the soil, depending on whether the ambient air is colder or warmer than the soil. In winter, the heat pump removes the heat from the fluid, upgrades it to a higher temperature for use in the building, typically in under-floor heating. A distribution system is needed to transfer the heat extracted from the ground by the heat pump.The heat is often in the form of hot water and is distributed around the dwelling by radiators or a low temperature underfloor heating system.
Payback and Maintance
The initial capital costs of installing a Geothermal Heat Pump system is usually higher than other conventional central heating systems. However, under the Greener Homes Scheme, there are now grants available which will reduce initial costs significantly. A large proportion of the outlay will be for the purchase and installation of the ground collector. The system is among the most energy efficient and cost effective heating and cooling systems available.
Typically, four units of heat are generated for every unit of electricity used by the heat pump to deliver it, and the payback is typically about 8- 10 years. The life expectancy of the system is around 20 years. Once installed a heat pump requires very little maintenance and anyone installing a heat pump should speak with their installer regarding a maintenance agreement.
Heat and Energy Gallery
Drilling for Energy
The heat is collected from the bedrock and the groundwater through a borehole 4.5 to 6.5 inches in diameter. The depth of the borehole is determined by the amount of energy needed for heating. If the energy demand is great, several boreholes can be connected together.
Air to Water
- This type of heat pump is ideal for retrofits or indeed is vertical/horizontal collector systems are not suitable.
- Can collect heat from the air in temperatures as low as -7 degrees
- This system will have to be fitted with a small supplementary back up system for when there is no heat in the temperature outside for the heat pump to draw from.
- Can be installed with existing oil/gas heating system in place, and use them as the supplementary back up system.
About Solar
Solar energy is the mother of most renewable energies on earth. The sun powers natural cycles on earth like the wind, water flow and plant growth.
But the sun is also such a reliable source of heat and light that we sometimes take it for granted. Generations have used glass and other materials and structures to capture and magnify the sun’s energy and these systems have gradually evolved to form the basis of mature techniques that are used today to harness solar energy
The most common application of solar thermal energy is solar water heating. Solar panels, generally located on a south-facing roof, transform solar radiation into heat. The heat produced during the day is stored in a large hot water cylinder, so that it can be used at any time. Solar water heating systems are generally sized to cover 50 to 60% of a household’s hot water (about 1 to 1.5 m2 of solar panel per person; 50 litres of water storage per m2 of panel). Such a system will provide almost all of your house’s hot water needs during the summer. This dramatically reduces the oil and gal costs and takes you one step further away from fossil fuel dependency.
Solar panels are not only suitable for DHW heating, but also as backup for your central heating. During the interim period, the solar system can support the central heating system. This considerably reduces your oil and gas consumption.
About Heat Recovery Systems
Fresh outside air is introduced through a weather grille. Upon entry into the ventilation system this air initially flows through a filter where it is purified and then preheated by a counter-current heat exchanger, from there it is supplied to the rooms to be ventilated via a system of ducts. The exhaust air is extracted via a pipe system from the areas where steam and odours are created (kitchen, bathroom, WC) and channeled to the ventilation air/exhaust air device.?Modern ventilation systems avoid the need for windows to be opened and prevent uncontrolled heat losses, especially during the heating season and also provide for greater security for you and your belongings. Subject to demand, various operating programs can be manually adjusted on the remote control or via the time switch.
Further ventilation system benefits;
• Comfortable and healthy ambient conditions
• Heating energy savings and protection of the environment, since air changes are matched to the actual demand
• Convenient and appropriate operation of domestic ventilation system by remote control
• Recovery of more that 90% of latent heat to reduce ventilation heating demand to a minimum, and lowering of heating costs.
• Cleaning of outside air by pollen filter and improvement of quality of life
• Prevention of mould and building damage through excessive humidity in the air.
• Compact design for high space efficiency, can be installed freestanding or wall mounted
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