Response to the following questions:
1. Today one gallon of "gasoline" costs $3.85. This gasoline contains 10% ethanol (E10). If the gasoline was 100% gasoline, how much should it cost? Assume that gasoline contains 115,400 BTU/gal and that ethanol contains 75,670 BTU/gal. ( $3.99/gal)
2. You need to calculate how much VOCs is released by your coating facility per year. For each of the following, calculate how much VOC is emitted per year. (These are as easy as they seem...)
a. Workers use a single spray gun with a capacity of 5 gallons per hour. The coating contains 75% VOC by weight and its density is 9.85 lbs/gal. The workers use this gun 8 hours/day for 250 days in a year.
b. Painters use 30 gallons of latex (water based) paint during the year. The paint contains 1.19 lbs of VOC per gallon.
c. Painters use 7 gallons of oil based trim paint per year. Oil base paint contains 3.69 lbs of VOC per gallon.
d. Workers use 9 gallons of clean-up solvent per year. You can assume that the solvent is 100% VOC and that the specific gravity is 0.87.
e. Your facility installed 5000 ft2 new carpet this year that emits 0.2 mg VOC/ m2 of carpet per hour. (~74,000 lb VOC/year)
3. Currently Penn State produces 20,000 MWh of electricity from its coal-fired power plant by burning 7500 metric tons of coal. Coal produces 6.67 kWh of heat for every kg of coal.
a. What is the efficiency of the power plant?
b. How many kg of CO2 are produced every year by burning coal at Penn State? (48 million lbs)
c. Penn State will switch to natural gas. Methane has a heat capacity of 1011 BTU/ft3 and a density of 0.042 lb/ft3. How many kgs of CO2 will be released if the new plant is 55% efficient? (14 million lbs)
d. If 1% of the methane leaks, how much equivalent kgs of CO2 total will be produced? (15 million lbs)
4. The US uses 8.5 million tons of cement per year. You need 120 kWh of electricity to make one ton of cement. Assume that natural gas has a heating content of 0.3 kWh heat/ft3, a density of 0.042 lb/ft3 and that it burns with an efficiency of 55%.
a. Calculate the lbs of natural gas (CH4) required to produce enough energy to create 8.5 million tons of cement.
b. Calculate the totallbs of equivalent CO2 released if 99.5% of the methane is burned and 0.5% of the CH4 is released into the environment without being burned. Global Warming potential of CH4 = 23. (7.4 x 108lb CO2)
c. Calculate how many equivalent miles are driven per year per person to equal the amount of CO2 produced from the energy used in producing cement? The US population is 317 million people. Assume that the average car gets 27.5 mpg and that gasoline can be represented as C8H18 with a density of 6.15 lb/gal. (C = 12 g/mole, H = 1 g/mole, O = 16 g/mole)
5. Methane production is increasing with the advent of new drilling technologies. There is much debate in scientific literature about the environmental impact of burning natural gas (methane) vs. coal. In the US we use approximately 4,000 TWh (1 TWh = 1012Wh) of electricity per year.
a. Calculate the lbs of CO2 released when creating this electricity with coal-fired power plants with an average efficiency of 40%. (9.7 x 1012lb CO2)
b. Calculate the lbs of CO¬2 saved when increasing the average efficiency of the power plants to 48%.
c. What are the equivalent miles driven per car per year in the US? Assume there are 250 million cars in the US and the average mpg is 24.8. Assume the density of gasoline is 6.15 lb/gal with a molecular formula of C8H18¬. (8320 miles/year-car)
d. Calculate the lbs of CO2 produced if all the electricity came from natural gas power plants. Assume an efficiency of 38%.
e. The argument in the scientific literature is that methane leaks during the production of electricity. Assume that the heating content of 1 kg of natural gas is 15.4 kWh. This methane has a Global Warming Potential of 23. Calculate the new lbs of CO2 produced (including CO2 equivalents) if 8% of the methane leaks in the production of electricity. (6.5 x 1012lb CO2)
6. ) Pennsylvania is the fourth leading coal producing state, mining 55 million tons of coal last year. They used this to produce 500 trillion BTU of electricity. Pennsylvania power plants emitted 130,683 tons of NOx, or about 80 percent of all the NOx emitted in the state.
a. Assuming the heating content is 13,200 BTU/lb of coal, calculate the efficiency of coal-fired power plants in PA. (34.4%)
Calculate how many lbs of NOx would be saved if the efficiency was changed to 42%. Assume you still need to provide 500 trillion Btu of electricity. (4.7 x 107lbsNOx per year
Response to the following Multiple Choice Questions:
Q1)The majority of CO emissions comes from:
1) transportation
2)industry
3)electric power industry
4)agriculture
Q2) The majority of SOx comes from:
1) combustion of coal
2) combustion of natural gas
3) combustion of gasoline
4) agriculture
Q3) Which of the following is considered a VOC?6
1) benzene (C6H6)
2) NOx
3) methane
4) ozone (O3)
Q4) Which of the following are caused by incomplete combustion in vehicles?
1) CO and VOCs
2) CO and NOx
3) SOx and NOx
4) CO2 and CO
Q5) the catalytic Converter converts
1) CO to CO2 and NOx to N2
2) CO to CO2 and NOx to N2
3) CO2 to CO and N2 to NOx
4) CO2 to CO and N2 to NOx
Q6) Which of the following contributes to the ozone hole?
1) CFCs only
2) CFCs and methane
3) methane only
4) N2O
Q7) Which of the following does NOT contribute to global climate change?
1) NOx
2) CFCs
3) methane
4) CO2
Q8) The efficiency of a coal-fired power plant is 42%. The plant produces 20,000 MWh of electricity. Calculate the MWh of heat produced from burning the coal.
1) 47,619 MWh of heat
2) 8,400 MWh of heat
3) 20,000 MWh of heat
4)27,619 MWh of heat
Q9) 100 lb of methane is burned. How many lbs of CO2 are produced?
1) 275 lbs CO2
2) 100 lb CO2
3) 36.3 lb CO2
4) 2300 lb CO2
Q10) 100 lb of methane is released (instead of burned). How many lbs of CO2 equivalent are produced?
1) 2300 lb CO2 equivalent
2) 275 lb CO2 equivalent
3) 36.3 lb CO2 equivalent
4) 100 lb of CO2 equivalent
Q11) Which one is more toxic?
1) PM2.5
2) PM10
3) they are the same
Q12) What kind of radiation causes cancer?
1) UV radiation
2) IR radiation
3) visible radiation
Q13) What kind of radiation is emitted as heat?
1) IR radiation
2) UV radiation
3) visible radiation
Q14) Which of the following has the highest global warming potential?
1) HFC23
2) CFC115
3) methane
4) N2O
Q15) Which of the following contributes most to global climate change?
1) CO2
2) N2O
3) CFCs
4) SOx