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Title: Field Demonstration of a High-Efficiency Packaged Rooftop Air Conditioning Unit at Fort Gordon, Augusta, GA

Abstract

As part of a larger program targeting the market transformation of packaged rooftop air conditioning, five high-efficiency rooftop air conditioning products were selected in 2002 by the U.S. Department of Energy (DOE) under the Unitary Air Conditioner (UAC) Technology Procurement (http://www.pnl.gov/uac). In February 2003, Fort Gordon in Augusta, Georgia was chosen as the demonstration site. With the goal of validating the field performance and operation of one of the awarded products, a 10-ton high-efficiency packaged rooftop unit (RTU) manufactured by Global Energy Group (GEG) was installed at Fort Gordon in October 2003. Following equipment installation, power metering, air- and refrigerant-side instrumentation was installed on the GEG RTU and a 4-year old typical-efficiency 20-ton RTU manufactured by AAON . The GEG and AAON units were instrumented identically and operated May through July, 2005, to observe performance under a range of conditions. Based on the data collected as part of this demonstration, the GEG equipment performed at least 8% better in stage-1 (single compressor running) cooling and at least 16% better in stage-2 (both compressors running) than the baseline AAON equipment. Performance comparisons are based on what we call application EER normalized to equivalent specific fan power. The full-load, specific-fan-power-normalized application EERsmore » at ARI design conditions were 10.48 Btu/Wh for the GEG and 9.00 Btu/Wh for the baseline machine. With a cost premium of nearly 50%, and slightly higher maintenance costs, the life-cycle cost analysis shows that the GEG technology pays for itself--a positive net-present value (NPV)--only in climates and buildings with long cooling seasons. Manufacture of this equipment on a larger scale can be expected to reduce costs to the point where it is more broadly cost-effective. The assumed 10-ton baseline and new-technology unit costs are $3824.00 and $5525.00 respectively. If the new technology cost is assumed to drop as sales increase to $4674.50 for a 10-ton unit (i.e. the original cost difference is halved), the life-cycle costs improve. A grid of first cost, annual maintenance cost and electricity price is enumerated and the results presented in the report show the sensitivity of life cycle cost to these three financial parameters in each of eight different climates.« less

Authors:
; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
894472
Report Number(s):
PNNL-15746
400403209; TRN: US200701%%474
DOE Contract Number:
AC05-76RL01830
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; AIR CONDITIONERS; AIR CONDITIONING; BLOWERS; CLIMATES; COMPRESSORS; DESIGN; ELECTRICITY; LIFE-CYCLE COST; MAINTENANCE; PRICES; PROCUREMENT; SALES; SEASONS; SENSITIVITY; TRANSFORMATIONS; market transformation; energy efficient; package air-conditioning; technology demonstration; ARI; capacity; EER; performance

Citation Formats

Armstrong, Peter R., Sullivan, Gregory P., and Parker, Graham B. Field Demonstration of a High-Efficiency Packaged Rooftop Air Conditioning Unit at Fort Gordon, Augusta, GA. United States: N. p., 2006. Web. doi:10.2172/894472.
Armstrong, Peter R., Sullivan, Gregory P., & Parker, Graham B. Field Demonstration of a High-Efficiency Packaged Rooftop Air Conditioning Unit at Fort Gordon, Augusta, GA. United States. doi:10.2172/894472.
Armstrong, Peter R., Sullivan, Gregory P., and Parker, Graham B. Fri . "Field Demonstration of a High-Efficiency Packaged Rooftop Air Conditioning Unit at Fort Gordon, Augusta, GA". United States. doi:10.2172/894472. https://www.osti.gov/servlets/purl/894472.
@article{osti_894472,
title = {Field Demonstration of a High-Efficiency Packaged Rooftop Air Conditioning Unit at Fort Gordon, Augusta, GA},
author = {Armstrong, Peter R. and Sullivan, Gregory P. and Parker, Graham B.},
abstractNote = {As part of a larger program targeting the market transformation of packaged rooftop air conditioning, five high-efficiency rooftop air conditioning products were selected in 2002 by the U.S. Department of Energy (DOE) under the Unitary Air Conditioner (UAC) Technology Procurement (http://www.pnl.gov/uac). In February 2003, Fort Gordon in Augusta, Georgia was chosen as the demonstration site. With the goal of validating the field performance and operation of one of the awarded products, a 10-ton high-efficiency packaged rooftop unit (RTU) manufactured by Global Energy Group (GEG) was installed at Fort Gordon in October 2003. Following equipment installation, power metering, air- and refrigerant-side instrumentation was installed on the GEG RTU and a 4-year old typical-efficiency 20-ton RTU manufactured by AAON . The GEG and AAON units were instrumented identically and operated May through July, 2005, to observe performance under a range of conditions. Based on the data collected as part of this demonstration, the GEG equipment performed at least 8% better in stage-1 (single compressor running) cooling and at least 16% better in stage-2 (both compressors running) than the baseline AAON equipment. Performance comparisons are based on what we call application EER normalized to equivalent specific fan power. The full-load, specific-fan-power-normalized application EERs at ARI design conditions were 10.48 Btu/Wh for the GEG and 9.00 Btu/Wh for the baseline machine. With a cost premium of nearly 50%, and slightly higher maintenance costs, the life-cycle cost analysis shows that the GEG technology pays for itself--a positive net-present value (NPV)--only in climates and buildings with long cooling seasons. Manufacture of this equipment on a larger scale can be expected to reduce costs to the point where it is more broadly cost-effective. The assumed 10-ton baseline and new-technology unit costs are $3824.00 and $5525.00 respectively. If the new technology cost is assumed to drop as sales increase to $4674.50 for a 10-ton unit (i.e. the original cost difference is halved), the life-cycle costs improve. A grid of first cost, annual maintenance cost and electricity price is enumerated and the results presented in the report show the sensitivity of life cycle cost to these three financial parameters in each of eight different climates.},
doi = {10.2172/894472},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Mar 31 00:00:00 EST 2006},
month = {Fri Mar 31 00:00:00 EST 2006}
}

Technical Report:

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