Emmaleigh Irish PHYS 301 Professor Cadena Homework 5 1. What are the reasons for the decrease in the U.S. crude oil production since 1970? U.S. crude oil production has decreased since 1970 due to an increase in production costs and decrease in the introduction of new oil reserves. 13. If all of our needs for oil were to be provided by that available from the estimated reserves located in the Arctic National Wildlife Reserve, how long would that supply last, assuming no growth in demand? If all our needs for oil were met by the estimated reserves in the Arctic National Wildlife Reserve, that supply would last for about 2 years (24 months). 14. A gas-fired turbine generator for producing electricity has an efficiency of about 50%. How many cubic feet would be needed to produce 1000 MWe for one year? Unit conversion: 1000 Btu = 0.293 kW-hr 1000 MW/0.50 = 2000 MW = 2x10
6
kW (2x10
6
kW)(24 hrs/day)(365 days/year) = 1.75x10
10
kW-hr/year (1.75x10
10
kW-hr/year)( 1 cubic foot/0.293 kW-hr) = 5.13x10
10
cubic feet 16. For a gasification project being planned, 26,000 tons of coal per day will be used to produce 250,000,000 ft
3
/day of natural gas. If the coal is rated at 8700 Btu/lb and the gas at 950 Btu/ft
3
, what will be the efficiency of this plan? (26,000 tons/day)(2000 lbs/1 ton)(8700 Btu/lb) = 4.524x10
11 Btu/day (250,000,000 ft
3
/day)(950 Btu/ft
3
) = 2.375x10
11
btu/day 2.375/4.524 = 52.5% efficency
