Details 1. When remodeling old homes, owners often choose to replace single pane windows with double pane windows (two glass panes separated by a layer of gas). How does the addition of a gas layer between the panes improve thermal efficiency of the home? 2. Calculate how much heat must be removed from a 1.0 kg bucket of water to 1. Cool the water from 30 C to OC. (answer: ~126KJ) 2. Freeze the water in the bucket completely. (answer: ~334KJ) 3. Given that the thermal conductivityes of wood, straw insulation, and drywall are: 0.12, 0.09, 0.17 W/(m C) respectively. Determine the rate of cooling of a 25 degree Celsius room on a 10 degree Celsius day, through a 10 m wall constructed with a 1/2" of drywall, 4" thick straw insulation panels, and 1/4" cedar siding. (answer ~119 Watts --- the previous posted answer of 1.2W was a mistake) 4. At what temperature will a Celsius thermometer & Fahrenheit thermometer read the same value? (answer: -40 degrees) 5. The United States Power plants consumed 39.5 quadrillion Btus of energy and produced 3.675 trillion KWh of electricity. What is the average efficiency of the power plants in the U.S.? (answer: ~32%) 6. Yet the energy efficiency of a power plant is about 35%, and the efficiency of automobiles is about 25%. Thus, over 62% of the total primary energy in the U.S. is used in relatively inefficient conversion processes. What are the challenges to increasing efficiencies? What are some measures that automakers or power plants have taken to improve efficiency