A manufacturing factory located at 30° N latitude has a window area 35 m2 that consists of double- pane windows made of clear glass (SHGC = 0.766) as given in the Figure Q2. To reduce the solar heat gain on a hot day, a reflective film that reduce the SGHC to 0.261 is considered. The building need cooling during the months of June, July, August and September and need heating during the months of October through April. The average daily solar heat fluxes incident on the west side of this latitude is given in the Table Q2 below. The unit cost of electricity and the natural gas are RM 0.30/kWh and RM1.75/therm, respectively. If the coefficient of performance of the cooling system is 3.0 and the efficiency of the furnace is 0.80. Determine: i. the net annual cost savings due to installing reflective coating on the windows ii. the simple payback period if the installation cost of the reflective film is RM 70/m²

A manufacturing factory located at 30° N latitude has a window area 35 m2 that consists of double- pane windows made of clear glass (SHGC = 0.766) as given in the Figure Q2. To reduce the solar heat gain on a hot day, a reflective film that reduce the SGHC to 0.261 is considered. The building need cooling during the months of June, July, August and September and need heating during the months of October through April. The average daily solar heat fluxes incident on the west side of this latitude is given in the Table Q2 below. The unit cost of electricity and the natural gas are RM 0.30/kWh and RM1.75/therm, respectively. If the coefficient of performance of the cooling system is 3.0 and the efficiency of the furnace is 0.80. Determine: i. the net annual cost savings due to installing reflective coating on the windows ii. the simple payback period if the installation cost of the reflective film is RM 70/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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.55P

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