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RESIDENTIAL ENERGY BASICS
ANSWERS TO TEXTBOOK QUESTIONS AND EXERCISES
1. It is important to surround a person with warm surfaces so the person can benefit from
3. A surface that is cooling from a high temperature stops emitting visible radiation at
4. Thermal radiation has a lower wavelength than visible light. Both are types of
6. Conduction heat flow will affect thermal comfort when heat from a warm building travels
7. Natural convection occurs without the use of blowers, fans, or circulators to cause fluid
8. Ultraviolet radiation has higher wavelengths than visible light. Infrared radiation has
10. The thermal efficiency of the device is calculated by dividing the measured useful heat
12. One kilowatt hour of electric resistance heat is equivalent to 3412 Btu. The claim that the
13. A 1,000 gallon tank of 180 degree water has higher entropy than a burning match. The
15. Examining energy conservation before considering a renewable energy system is wise,
16. A raised heel truss creates a larger space between the intersection of the roof and the
17. Heat is a form of energy, while temperature is a measurement of how much heat energy
19. The cost/benefit ratio of the high-efficiency boiler is 6500/300, or 21.6. The cost/benefit
20. Thermal mass is necessary in passive solar buildings to allow heat to be stored and
of intense sunlight.
21. Some designers prefer to rotate a passive solar building slightly east rather than due south
22. Insulation blankets should not be installed on top of gas-fired water heaters due to the
24. Counterflow in a graywater heat exchanger means the cold water passes upward and the
25. Insulation is imperative on the piping of a recirculating hot water distribution system to
26. A demand operated recirculating hot water system has a timer that allows the recirculator
28. Unit price of natural gas: (1.25*10)/0.9 = $13.88 per MMBtu.
29. A balanced ventilation system directs airflow into and out of a building. Because it
30. The recommended ventilation rate for an 1850 sq. ft. home with 3 bedrooms is
32. The core of a heat recovery ventilator is a compact heat exchanger constructed of