Sustainable Energy
2nd Edition
ISBN: 9781337551663
Author: DUNLAP, Richard A.
Publisher: Cengage,
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Chapter 8, Problem 9P
To determine
Find the required minimum (ability of conduct heat)
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A wooden shelter has walls constructed of wooden planks 1.00 cm thick. If the exterior temperature is -20.0°C and the interior is 5.00°C, find the rate of energy loss through a wall that has dimensions 1.95 m by 2.30 m.
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- For a building located in Madrid, Spain with annual heating degree-days (dd) of 4654, a heating load (heat loss) of 30,000 kj/h, and a design temperature difference of 30° C (20° C indoor), estimate the annual energy consumption. If the building is heated with a furnace with an efficiency of 92%, how muchgas is burned to keep the home at 20° C? State your assumptions.arrow_forwardA coal-fired power plant discharges 1 m^3/s of cooling water into a river, which has a flow of 9 m^3/s and a temperature of 20 degree C. According to the regulation, the temperature in the river immediately below the discharge cannot be increased by higher than 1 degree C. Therefore, what is the highest temperature of the cooling water is allowed for discharge?arrow_forwardCalculate the heat loss from a double-pane glass window consisting of two pieces of glass, each having a thickness of 10 mm with a thermal conductivity of k = 1.3 W/m.K . The two glass panes are separated by an air gap of 7 mm. Assume thermal conductivity of air to be k = 0.022 W/m.K .arrow_forward
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