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Title: High-Efficiency Variable Dehumidification for Air Conditioners: ClimaStat

Abstract

Advantek has successfully developed the first low-cost technology offering significant improvement in both Seasonal Energy Efficiency (SEER) and comfort & humidity control. A production prototype was constructed based on a commercial roof top package unit. The prototype was operated under a wide range of psychrometric conditions. Test data was analyzed to identify refinements, which were implemented to further improve performance in an iterative procedure that resulted in a fully optimized technology. The latest results show an increase in dehumidification capacity of 56% with ClimaStat™ in full dehumidify mode vs. with ClimaStat™ off. Dehumidification improved by a factor of 1.7 to 1.9 – meaning that the unit can provide nearly twice the water removal per unit of sensible cooling load. Performance testing results have been consistent, verifiable and repeatable. . ClimaStat™ cost-effectively controls humidity on-demand and improves indoor air quality while reducing annual energy costs. Test data clearly shows that ClimaStat™ costs 20% to 60% less to operate. ClimaStat™ is ready for market.

Authors:
Publication Date:
Research Org.:
Advantek Consulting, Inc.
Sponsoring Org.:
USDOE - Office of Energy Efficiency and Renewable Energy (EE) Inventions and Innovations Program
OSTI Identifier:
922139
Report Number(s):
DOE-GO13003-1
TRN: US200806%%200
DOE Contract Number:
FG36-03GO13003
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; AIR CONDITIONERS; AIR QUALITY; CAPACITY; COOLING LOAD; ENERGY ACCOUNTING; ENERGY EFFICIENCY; HUMIDITY; HUMIDITY CONTROL; INDOORS; MARKET; PERFORMANCE; PERFORMANCE TESTING; PRODUCTION; ROOFS; WATER REMOVAL; Air Conditioning, energy efficiency, EER, SEER, dehumidification, humidity, dehumidify, SHR, mold, IAQ, indoor air quality

Citation Formats

West, Michael K., Ph.D. P.E. High-Efficiency Variable Dehumidification for Air Conditioners: ClimaStat. United States: N. p., 2006. Web. doi:10.2172/922139.
West, Michael K., Ph.D. P.E. High-Efficiency Variable Dehumidification for Air Conditioners: ClimaStat. United States. doi:10.2172/922139.
West, Michael K., Ph.D. P.E. Sun . "High-Efficiency Variable Dehumidification for Air Conditioners: ClimaStat". United States. doi:10.2172/922139. https://www.osti.gov/servlets/purl/922139.
@article{osti_922139,
title = {High-Efficiency Variable Dehumidification for Air Conditioners: ClimaStat},
author = {West, Michael K., Ph.D. P.E.},
abstractNote = {Advantek has successfully developed the first low-cost technology offering significant improvement in both Seasonal Energy Efficiency (SEER) and comfort & humidity control. A production prototype was constructed based on a commercial roof top package unit. The prototype was operated under a wide range of psychrometric conditions. Test data was analyzed to identify refinements, which were implemented to further improve performance in an iterative procedure that resulted in a fully optimized technology. The latest results show an increase in dehumidification capacity of 56% with ClimaStat™ in full dehumidify mode vs. with ClimaStat™ off. Dehumidification improved by a factor of 1.7 to 1.9 – meaning that the unit can provide nearly twice the water removal per unit of sensible cooling load. Performance testing results have been consistent, verifiable and repeatable. . ClimaStat™ cost-effectively controls humidity on-demand and improves indoor air quality while reducing annual energy costs. Test data clearly shows that ClimaStat™ costs 20% to 60% less to operate. ClimaStat™ is ready for market.},
doi = {10.2172/922139},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Apr 30 00:00:00 EDT 2006},
month = {Sun Apr 30 00:00:00 EDT 2006}
}

Technical Report:

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  • The US DOE initiated this project to evaluate the performance of an air conditioner retrofit program in Austin, Texas. The City's Austin's Resource Management Department pursued this project to quantify the retrofit effect of replacing low-efficiency air conditioners with high-efficiency air conditioners in single-family detached homes. If successfully implemented, this retrofit program could help defer construction of a new power plant which is a major goal of this department. The project compares data collected from 12 houses during two cooling seasons under pre-retrofit and then post-retrofit air conditioner units. The existing low-efficiency air conditioners were monitored during the 1987 coolingmore » season, replaced during the 1987--88 heating season with new, smaller sized, high-efficiency units, and then monitored again during the 1988 cooling season. Results indicated that the air conditioner retrofits reduce the annual air conditioner electric consumption and peak electric demand by an average of 38%. When normalized to the nominal capacity of the air conditioner, average demand savings were 1.12 W/ft{sup 2} and estimated annual energy savings were 1.419 kWh/ft{sup 2}. Individual air conditioner power requirements were found to be a well defined function of outdoor temperature as expected. In the absence of detailed data, estimates of the peak demand reductions of new air conditioners can be made from the manufacturer's specifications. Air conditioner energy consumption proved to be strongly linear as a function of the outdoor temperature as expected when taken as an aggregate. No noticeable differences in the diversity factor of the air conditioner usage were found. Analysis of the retrofit effect using PRISM yields estimates of the reduction in normalized annual consumption (NAC) and annual cooling consumption of 12% and 30%. 2 refs., 11 figs., 17 tabs.« less
  • A field test involving 104 houses was performed in Tulsa, Oklahoma, to measure the air-conditioning electricity consumption of low-income houses equipped with window air conditioners, the reduction in this electricity consumption attributed to the installation of energy conservation measures (ECMs) as typically installed under the Oklahoma Weatherization Assistance Program (WAP), and the reduction achieved by the replacement of low-efficiency window air conditioners with high-efficiency units and the installation of attic radiant barriers. Air-conditioning electricity consumption and indoor temperature were monitored weekly during the pre-weatherization period (June to September 1988) and post-weatherization period (May to September 1989). House energy consumption modelsmore » and regression analyses were used to normalize the air-conditioning electricity savings to average outdoor temperature conditions and the pre-weatherization indoor temperature of each house. The average measured pre-weatherization air-conditioning electricity consumption was 1664 kWh/year ($119/year). Ten percent of the houses used less than 250 kWh/year, while another 10% used more than 3000 kWh/year. An average reduction in air-conditioning electricity consumption of 535 kWh/year ($38/year and 28% of pre-weatherization consumption) was obtained from replacement of one low-efficiency window air conditioner (EER less than 7.0) per house with a high-efficiency unit (EER greater than 9.0). For approximately the same cost, savings tripled to 1503 kWh/year ($107/year and 41% of pre-weatherization consumption) in those houses with initial air-conditioning electricity consumption greater than 2750 kWh/year. For these houses, replacement of a low-efficiency air conditioner with a high-efficiency unit was cost effective using the incremental cost of installing a new unit now rather than later; the average installation cost for these houses under a weatherization program was estimated to be $786. The general replacement of low-efficiency air conditioners (replacing units in all houses without considering pre-weatherization air-conditioning electricity consumption) was not cost effective in the test houses. ECMs installed under the Oklahoma WAP and installed in combination with an attic radiant barrier did not produce air-conditioning electricity savings that could be measured in the field test. The following conclusions were drawn from the study: (1) programs directed at reducing air-conditioning electricity consumption should be targeted at clients with high consumption to improve cost effectiveness; (2) replacing low-efficiency air conditioners with high-efficiency units should be considered an option in a weatherization program directed at reducing air-conditioning electricity consumption; (3) ECMs currently being installed under the Oklahoma WAP (chosen based on effectiveness at reducing space-heating energy consumption) should continue to be justified based on their space-heating energy savings potential only; and (4) attic radiant barriers should not be included in the Oklahoma WAP if alternatives with verified savings are available or until further testing demonstrates energy savings or other benefits in this type of housing.« less
  • A field test Involving 104 houses was performed in Tulsa, Oklahoma, to measure the air-conditioning electricity consumption of low-income houses equipped with window air conditioners, the reduction in this electricity consumption attributed to the installation of energy conservation measures (ECMS) as typically installed under the Oklahoma Weatherization Assistance Program (WAP), and the reduction achieved by the replacement of low-efficiency window air conditioners with high-efficiency units and the installation of attic radiant barriers. Air-conditioning electricity consumption and indoor temperature were monitored weekly during the pre-weatherization period (June to September 1988) and post-weatherization period (May to September 1989). House energy consumption modelsmore » and regression analyses were used to normalize the air-conditioning electricity savings to average outdoor temperature conditions and the pre-weatherization indoor temperature of each house. The following conclusions were drawn from the study: (1) programs directed at reducing air-conditioning electricity consumption should be targeted at clients with high consumption to improve cost effectiveness; (2) replacing low-efficiency air conditioners with high-efficiency units should be considered an option in a weatherization program directed at reducing air-conditioning electricity consumption; (3) ECMs currently being installed under the Oklahoma WAP (chosen based on effectiveness at reducing space-heating energy consumption) should continue to be justified based on their space-heating energy savings potential only; and (4) attic radiant barriers should not be included in the Oklahoma WAP if alternatives with verified savings are available or until further testing demonstrates energy savings or other benefits in this typo of housing.« less
  • A field test Involving 104 houses was performed in Tulsa, Oklahoma, to measure the air-conditioning electricity consumption of low-income houses equipped with window air conditioners, the reduction in this electricity consumption attributed to the installation of energy conservation measures (ECMS) as typically installed under the Oklahoma Weatherization Assistance Program (WAP), and the reduction achieved by the replacement of low-efficiency window air conditioners with high-efficiency units and the installation of attic radiant barriers. Air-conditioning electricity consumption and indoor temperature were monitored weekly during the pre-weatherization period (June to September 1988) and post-weatherization period (May to September 1989). House energy consumption modelsmore » and regression analyses were used to normalize the air-conditioning electricity savings to average outdoor temperature conditions and the pre-weatherization indoor temperature of each house. The following conclusions were drawn from the study: (1) programs directed at reducing air-conditioning electricity consumption should be targeted at clients with high consumption to improve cost effectiveness; (2) replacing low-efficiency air conditioners with high-efficiency units should be considered an option in a weatherization program directed at reducing air-conditioning electricity consumption; (3) ECMs currently being installed under the Oklahoma WAP (chosen based on effectiveness at reducing space-heating energy consumption) should continue to be justified based on their space-heating energy savings potential only; and (4) attic radiant barriers should not be included in the Oklahoma WAP if alternatives with verified savings are available or until further testing demonstrates energy savings or other benefits in this typo of housing.« less
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