Question

A remotely located air sampling station can be powered by solar cells or by running an electric line to the site and using conventional power. Solar cells will cost $15,000 to install and will have a useful life of 4 years with no salvage value. Annual costs for inspection, cleaning, etc. are expected to be $1,500. A new power line will cost $13,000 to install, with power costs expected to be $1,200 per year. Since the air sampling project will end in 4 years, the salvage value of the line is considered to be zero. At an interest rate of 14% per year, which alternative should be selected on the basis of a future worth analysis?

Answer 1

Since the total future worth of running an electric line of $19,353.42 is less than the total future worth of solar cells is $24,132.22, it will be cheaper to run an electric line than to use solar cells. So running an electric line should be the answer.