A manufacturing facility located at 32° N latitude has a glazing area of 60 m² facing west that consists ofdouble pane windows made of clear glass (SHGC = 0.766). To reduce the solar heat gain in summer, areflective film that will reduce the SHGC to 0.35 is considered. The cooling season consists of June, July,August, and September, and the heating season, October through April. The average daily solar heat fluxesincident on the west side at this latitude are 2.35, 3.03, 3.62, 4.00, 4.20, 4.24, 4.16, 3.93, 3.48, 2.94, 2.33,and 2.07 kWh/day · m² for January through December, respectively. Also, the unit costs of electricity andnatural gas are $0.09/kWh and $0.45/therm., respectively. If the coefficient of performance of the coolingsystem is 3.2 and the efficiency of the furnace is 0.90, determine the net annual cost savings due to installingreflective coating on the windows. Also, determine the simple payback period if the installation cost ofreflective film is $20/m².Answers: $53, 23 years

GIven: A=60 m2 COP=3.2 Efficiency=0.9 cost of electricity= $0.09 /kWh Cost of natural gas= $0.45…

system is 3.2 and the efficiency of the furnace is 0.90, determine the net annual cost savings due to installing reflective coating on the windows. Also, determine the simple payback period if the installation cost of reflective film is $20/m2.

system is 3.2 and the efficiency of the furnace is 0.90, determine the net annual cost savings due to installing reflective coating on the windows. Also, determine the simple payback period if the installation cost of reflective film is $20/m2.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter11: Heat Transfer By Radiation

Section: Chapter Questions

Problem 11.22P

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