Problem
NRG Energy plans to construct a giant solar plant in Santa Teresa, NM to supply electricity to 30,000 southern NM and west TX homes. The plant will have 390,000 heliostats to concentrate sunlight onto 32 water towers to generate steam. NRG will spend $6.6 million in constructing the plant and $330,000 per year in operating it. If a salvage value of 10% of the initial cost is assumed, how much will the company have to make each year for 15 years in order to recover its investment at a MARR of 10% per year?