I think the work I have done is wrong since it wants the yearly input but I\'m n

Question

I think the work I have done is wrong since it wants the yearly input but I'm not sure.. Greatly appreciated if you could solve this.

Thank you

Take the Energy Challenge I Total: 40 points (10 for each calculation) The U.S. is very oil dependent and imports much of its oil. Below you are given a hypothetical situation in which you are to calculate the energy saved by replacing one conventional incandescent bulb with one compact fluorescent bulb in every American household Given the assumptions below, calculate the energy required in Case A and Case B. Then answer the questions using some of the Information in the "basic energy unit" sheel below. Show all work on a separate sheet and be sure to Include proper units. Assumptions for both Case A and B: There are 50 times 106 homes in the U.S. Each home has just one light bulb which runs one hour per day. Case A: All homes have a 75 watt incandescent bulb Case B: All homes have an 18 watt compact fluorescent bulb Using the information above, answer the following 4 questions. Hint: As you set up your calculations, pay close attention to the units. There is a table of some unit conversion factors included below. How the units cancel each other in the calculation will help you use logic to construct your equations. You must show your work - step by step to get credit. How much energy per year do the homes in Case A use for lighting; (10 points) 50 times 106 times 75 = 3.75 times109 watts/yr. How much energy per year do the homes In Case B use for lighting; (10 points) 50 times 106 times 18 = 9.0 times108 watts/yr. How much total energy is saved annually by replacing one 75-watt incandescent bulb with an 18-watt compact fluorescent bulb in all the homes? (10 points) 3.75 times 109 - 9.0 times 108 = 2.85 times 109 watts/gr would be saved per year of replaced one light bulb. How many barrels of oil per year doet this energy savings represent? (10 points) (hint: use the quad - see energy unit below) Additional note (food for thought): A compact fluorescent bulb lasts 10 times longer (average life of incandescent is 1,000 hours while an average compact fluorescent bulb last about 10,000 hours). Thus we would have many less bulbs in landfills Imagine the potential energy savings since each house has many bulbs and they burn more than one hour per day. Your calculation assumed only 1 bulb per home operating for just 1 hour per day. Back units used to measure energy These are to help you with the calculation. If you pay attention to the units, they will help you with the energy conversions you need to calculate the answers. Exajoule = 1018 Joules (j) Kilowatt-hour (kwh) - measures electrical usage (power used over some length of time) 1 kwh operates one 100 watt bulb for 10 hours (100 times 10 = 1000) Quad = 1.05 times 1015 Kilojoules(kJ) Quad = 2.93 times 1011 Kilowatt hours (kwh) 1 kwh = 3,412 BTU 1 Quad = 1 times 1015 BTU of energy (One Exajoule) 1 Quad = 171.5 mlllon barrels of oil A barrel holds 42 gallons of petroleum oil A barrel of motor gasoline produces 5.25 million BTU Thus - one gallon of petroleum produces 125,000 BTU BTU stands for British Thermal Unit - a standard measure for the amount of heat needed to raise the temperature of 1 pound of water by 1 degree Fahrenheit Natural gas is measured in cubic feet (ft3) 1 ft3 produces 1,031 BTU Therm = 100,000 BTU = 97 cubic feet (ft3) natural gas

Explanation / Answer

1) 1 hour a day = 60*60*365.25 seconds
E = P*time = 50*10^6*75* 365.25 =1.37E12 J per year

2)

50*10^6*18* 365.25= 3.29E11 J per year

3) 1.37E12 - 3.29E11=1.04E12 J per year saved

4) convert to quads

1.04E12/1.05E15 = 9.9E-4 Quads

now conver to barrels of oil

9.9E-4 * 171.5E6= 169785 barrels of oil

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