Saramarie Puzzanghera is considering two alternative systems to power a backup refrigerator for medicine at a...

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Saramarie Puzzanghera is considering two alternative systems to power a backup refrigerator for medicine at a remote hospital in Madagascar - see Table 1. System 1 would use solar panels and a DC-battery array. System 2 would use a gas-powered generator. The maximum power output ratings for both systems are adequate to meet all energy requirements. Repeatability can be assumed for both systems, and taxes and inflation can be ignored. The MARR is 5%. First cost P Useful life N Annual maintenance cost A Fuel cost F Fuel conversion rate (approx.) System 1 (solar + batteries) System2 (gas-powered generator) $50,000 $2000 20 years 7 years $50/yr $500/yr $0 $2.00 per gallon of gas 0.26 kW-hrs/gallon of Table 1: System comparison for Question 2(a) gas (i.) If the energy requirement is 500 kW-hrs per year, which system is the better alternative? [4 points] (ii.) If the energy requirement is X kW-hrs per year, what value of X would be required for the two systems to be equivalent? [4 points] (iii.) If the energy requirement is 500 kW-hrs per year, what useful life N of System 2 would be required for the two systems to be equivalent? [2 points] Saramarie Puzzanghera is considering two alternative systems to power a backup refrigerator for medicine at a remote hospital in Madagascar - see Table 1. System 1 would use solar panels and a DC-battery array. System 2 would use a gas-powered generator. The maximum power output ratings for both systems are adequate to meet all energy requirements. Repeatability can be assumed for both systems, and taxes and inflation can be ignored. The MARR is 5%. First cost P Useful life N Annual maintenance cost A Fuel cost F Fuel conversion rate (approx.) System 1 (solar + batteries) System2 (gas-powered generator) $50,000 $2000 20 years 7 years $50/yr $500/yr $0 $2.00 per gallon of gas 0.26 kW-hrs/gallon of Table 1: System comparison for Question 2(a) gas (i.) If the energy requirement is 500 kW-hrs per year, which system is the better alternative? [4 points] (ii.) If the energy requirement is X kW-hrs per year, what value of X would be required for the two systems to be equivalent? [4 points] (iii.) If the energy requirement is 500 kW-hrs per year, what useful life N of System 2 would be required for the two systems to be equivalent? [2 points]