Sunday, 26 June 2016: 9:45 AM-10:45 AM
HVAC Systems and Equipment
Chair:
Ersin Gercek, P.E., Real Engineering Services LLC
Absorption systems can be used in a variety of cooling and heating applications often simultaneously to improve overall system efficiency. This session introduces dual and triple lift (not stage) absorption systems with a case study. The session also covers modern absorption systems on district heating and cooling commercial water heating applications.
1 Practical Application of an Absorption Heat Pump to Commercial Water Heating
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Patrick Geoghegan, Ph.D., ORNL
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Commercial hot water heating in the US accounts for 780 Trillion Btu/year of primary energy use, with over half of this amount from natural gas fired heaters. A commercial absorption heat pump could achieve a level of savings much higher than possible by conversion to the best available non-heat-pump gas fired alternatives (instantaneous condensing). The ammonia-water system has the added advantage of zero Global Warming Potential and Ozone Depletion Potential. This seminar presents the development of a practical absorption heat pump cycle with laboratory-measured performance metrics, outlines potential installation layouts, and presents the economic case for adoption in commercial buildings.
2 Using Double and Triple Lift Single Stage Absorption to Save Energy
Utilizing low grade thermal energy and hot water for cooling is a great application for Double and Triple Lift absorbers. This presentation will cover a new Tire Plant in Tennessee that will use 185-131 F hot water to produce 300 tons of cooling. Currently there is a dearth of general understanding of what a double or triple lift unit is and therefore not many applications to date in North America. Traditional and well know single stage absorber cannot use hot water below 190F typically.
3 Absorption Heat Pumps for District Heating Applications
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Rajesh Dixit, Johnson Controls, Inc.
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Absorption heat pumps can be used for generating medium temp hot water (up to 195F) for district heating applications using a low grade waste heat source and a high grade heat source. With about 40% of heat coming from a very low grade source, which otherwise would be rejected to atmosphere, the coefficient of performance is about 1.7 and the economics becomes quite attractive. This source could be geothermal heat or process heat or even a condenser water loop by bypassing a cooling tower. Heat pumps have also been successfully utilized in waste to energy plants.
