geothermal india cooling india from the ground up about geothermal cooling

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1 about geothermal cooling

2 geothermal india about geothermal cooling Geothermal India is India s leading exponents of distributing, installing and servicing Geothermal Air-conditioning solutions in India. what is Geothermal and how does it work? Geothermal (or Geo-exchange) is a type of HVAC System (Heating, Venting, and Air-Conditioning). The earth absorbs almost 50% of all solar energy and remains a nearly constant temperature of 10 C (50 F) depending on geographic location. Working with an underground loop system, a geothermal unit utilizes this constant temperature to exchange energy between the building and the earth as needed for heating and cooling. In the summer, the system expels heat from buildings to the cooler earth via the loop system. This heat exchange process is natural and a highly efficient way to create a comfortable climate in buildings. A geothermal system differs from a conventional furnace or boiler by its ability to transfer heat versus the standard method of producing the heat and vice-versa. In winter, the system reverses and water circulating inside a sealed loop absorbs heat from the earth and carries it to the unit. Here it is compressed to a higher temperature and sent as warm air to the indoor system for distribution throughout the building. Geothermal is the most efficient Airconditioning system because the ground temperature stays stable and has no regard for the above ground ambient temperature. (continued)

3 A geothermal heat pump simply takes advantage of this low temperature energy source and pumps it up to a usable level to cool/heat the building. Geothermal Heat Pumps are very different as compared to "Air to Air" Heat Pumps. "Air to Air" Heat Pumps absorb energy from the outdoor air which fluctuates on a daily basis. Geothermal Heat Pumps draw energy out of the ground which stays relatively constant year round. interesting facts about geothermal air-conditioning. There are more than 1 million installations in the USA alone Geothermal technology has been successfully installed in more than 38 countries, including India Geothermal technology has successfully been installed in a variety of different climates from just below the arctic circle to 1 o north of the equator Geothermal technology has been successfully installed in areas with all major soil conditions. The largest installation is at Fort Polk, Louisiana, USA, where more than 4,000 homes are connected. Other notable installations include 4,700 TR (Tons of Refrigeration) used by Galt House in Louisville, Kentucky, USA Geothermal technology and its performance has been accredited and acknowledge by: US Department of Energy US Environmental Protection Agency (EPA) US General Accounting Office (GAO) American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE), whose standards are closely followed by their Indian counterparts, ISHRAE American Refrigeration Institute (ARI) product efficiency: the energy efficiency ratio EER. Efficiencies are defined by two parameters: The Coefficient of Performance (COP) and Energy Efficiency Ratio (EER). The steady state EER is defined as cooling output delivered in British Thermal Units per Hour (Btu/h) divided by the power input in watts. The COP is defined as the heating output divided by the power input in same units.

4 about geothermal cooling In case of a heat pump, this parameter is presented in slightly different ways for the heating and cooling modes. For cooling, the efficiency parameter is the Energy Efficiency Ratio (EER): EER = (Total Cooling Capacity in Btu/hr (Watts)) / (Power Input in Watts) For heating, the efficiency parameter is the Coefficient of Performance (COP): COP = (Heating Capacity in Btu/hr (Watts)) / (Power input in Btu/hr (Watts)) The general EER Values for different systems are: Air source conditioning system: 9.5 Cooling tower conditioning system: 10.5 Geothermal system: 18 It should be noted that the EER and COP are dependent on the Entering Water Temperature, Water Flow Rate, Airflow Rate and Entering Air Temperatures. Therefore, there is a need to be specific when comparing EER and COP of different units. The Environmental Protection Agency of the US has recognized Geothermal Technology (also known as GeoExchange) as the most efficient and environmentally friendly home heating and cooling system available. According to studies by the Environmental Protection Agency, Geothermal systems achieved a 48% increase in efficiency over gas furnaces, a 75% increase in efficiency over oil furnaces, and 40% greater efficiency over air source heat pumps. geothermal vs. conventional air conditioning. Nearly all conventional residential and light commercial buildings use refrigerant type air conditioning systems for cooling the interior space. These units all have the familiar outdoor condenser units. Variations include packaged heating/cooling units and air source heat pumps. All use outside air to cool the refrigerant, while rejecting heat into the surrounding air. These units will be referred to as "air source" equipment. Comparisons between Geothermal and conventional air source units are convoluted because of the sharp decrease in efficiency of air source equipment as a function of outside air temperature. Manufacturers of air source equipment are quick to post impressive EER and SEER (Seasonal Energy Efficiency Ratios) numbers on their "high efficiency" models, but a closer examination of the actual performance data shows that these lofty numbers do not correlate well under realistic installed conditions. A typical example of a 3-ton air source unit shows manufacturer's EER as However, a closer look at performance values yields a calculated EER value of 10.5, at rated conditions. This would represent a daytime temperature of about 32.2 C. When the outside temperature rises to 37.7 C, the air source EER drops to 9.2, which represents a reduction in efficiency of 12%. If outside temperature rises to 43.3 C, the air source EER drops even further to 7.7, which represents a reduction in efficiency of 27%. This means that the unit is requiring 27% more electricity to yield the same cooling.

5 Another aspect of the air source units is that the cooling ability of the unit is also a function of outside air temperature. A typical 3-ton unit can put out 3 tons of air conditioning when the outside air temperature (at the condenser) is 35 C. But, if the outside air temperature rises to 43.3 C, the unit can only put out approximately 2.6 tons, a reduction of 14%. Condensers that are clogged with dirt or debris will have even further reduction in efficiency. The performance of an appropriately designed geothermal system is independent of changes in outside air temperature and humidity. Since the temperature of the earth where the geothermal occurs is relatively unchanged throughout the year, Geothermal efficiency of both heating and cooling seasons is fixed. Typical efficiency for a 3-ton Geothermal Systems in cooling mode with entering water temperature (EWT) of 20 C is approximately 17 EER. The following table and chart gives a comparison of Geothermal to air source units as outside temperature varies: EER C 37.7 C 43.3 C Outside Temperature Geothermal Air Source EER Comparison Geothermal v. Air Source Cooling Outside Temp 32.2 C 37.7 C 43.3 C Geothermal Air Source As indicated in the table above, Geothermal systems for air conditioning are considerably more efficient than the conventional air source units. Simple calculations show that energy costs for a Geothermal are nominally 40% less than air source; 50% less than air source at 100 degrees; and can be as much as 55% less than air source as temperatures rise further. This efficiency analysis is attempted to examine like units for an "apples and apples" comparison. It has not included the effect of a Geothermal desuperheater, the hot water feature capability. With warm-hot climates, if the Geothermal is used to provide supplemental hot water to a conventional gas or electric water heater, the efficiency disparity becomes even greater. With the Geothermal desuperheater (HWG Hot Water Generator) in service, hot water

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