Measured energy savings and demand reduction from a reflective roof membrane on a large retail store in Austin

Konopacki, Steven J; Akbari, Hashem

doi:10.2172/787107

Title: Measured energy savings and demand reduction from a reflective roof membrane on a large retail store in Austin

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Abstract

In this study, we measured and documented summertime air-conditioning (a/c) daily energy savings and demand reduction from a reflective roof membrane retrofit on a large retail store in Austin, Texas. The original black rubber membrane was replaced with white thermoplastic resulting in a decrease in the average maximum roof surface temperature from 168 degrees F (76 degrees C) to 126 degrees F (52 degrees C). This building, with 100,000ft2 (9300m2) of roof area, yielded 3.6Wh/ft2 (39Wh/m2) in a/c average daily energy savings and 0.35W/ft2 (3.8W/m2) in average reduced demand. Total a/c annual abated energy and demand expenditures were estimated to be $7200 or $0.072/ft2 ($0.77/m2). Based on cost data provided by the building manager, the payback is instantaneous with negligible incremental combined labor and material costs. The estimated present value of future abated expenditures ranged from $62,000 to $71,000 over the baseline 13-year service life of the roof membrane.

Authors:: Konopacki, Steven J; Akbari, Hashem

Publication Date:: 2001-06-25

Research Org.:: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

Sponsoring Org.:: USDOE Assistant Secretary for Energy Efficiency and Renewable Energy. Office of Building Technology, State and Community Programs; Environmental Protection Agency (US)

OSTI Identifier:: 787107

Report Number(s):: LBNL-47149
R&D Project: 43BP01; TRN: AH200134%%177

DOE Contract Number:: AC03-76SF00098

Resource Type:: Technical Report

Resource Relation:: Other Information: PBD: 25 Jun 2001

Country of Publication:: United States

Language:: English

Subject:: 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; AIR CONDITIONING; EXPENDITURES; MEMBRANES; ROOFS; RUBBERS; SERVICE LIFE; TEXAS; THERMOPLASTICS; REFLECTIVE ROOF ENERGY SAVINGS AIR-CONDITIONING HEAT ISLAND

Citation Formats


                    Konopacki, Steven J, and Akbari, Hashem. Measured energy savings and demand reduction from a reflective roof membrane on a large retail store in Austin.  United States: N. p., 2001. 
        Web.  doi:10.2172/787107.

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                    Konopacki, Steven J, & Akbari, Hashem. Measured energy savings and demand reduction from a reflective roof membrane on a large retail store in Austin.  United States.  https://doi.org/10.2172/787107

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                    Konopacki, Steven J, and Akbari, Hashem. 2001.  
        "Measured energy savings and demand reduction from a reflective roof membrane on a large retail store in Austin".  United States.  https://doi.org/10.2172/787107.  https://www.osti.gov/servlets/purl/787107.

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@article{osti_787107,

  title        = {Measured energy savings and demand reduction from a reflective roof membrane on a large retail store in Austin},

  author       = {Konopacki, Steven J and Akbari, Hashem},

  abstractNote = {In this study, we measured and documented summertime air-conditioning (a/c) daily energy savings and demand reduction from a reflective roof membrane retrofit on a large retail store in Austin, Texas. The original black rubber membrane was replaced with white thermoplastic resulting in a decrease in the average maximum roof surface temperature from 168 degrees F (76 degrees C) to 126 degrees F (52 degrees C). This building, with 100,000ft2 (9300m2) of roof area, yielded 3.6Wh/ft2 (39Wh/m2) in a/c average daily energy savings and 0.35W/ft2 (3.8W/m2) in average reduced demand. Total a/c annual abated energy and demand expenditures were estimated to be $7200 or $0.072/ft2 ($0.77/m2). Based on cost data provided by the building manager, the payback is instantaneous with negligible incremental combined labor and material costs. The estimated present value of future abated expenditures ranged from $62,000 to $71,000 over the baseline 13-year service life of the roof membrane.},

  doi          = {10.2172/787107},

  url          = {https://www.osti.gov/biblio/787107},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {2001},

  month        = {6}

}

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