For many applications, especially remote site and small power applications, PV power is the most cost-effective option available, not to mention its environmental benefits. New PV modules generally retail for about $3,25 per peak watt, depending on quantities purchased. Batteries, inverters, and other balance of system components can raise the overall price of a PV system to over $10 - $15 per installed Watt. PV modules on the market today are guaranteed by manufacturer's from 10 to 20 years, while many of these should provide over 30 years of useful life. It is important when designing PV systems to be realistic and flexible, and not to overdesign the system or overestimate energy requirements (e.g., overestimating water-pumping requirements) so as not to have to spend more money than needed. PV conversion efficiencies and manufacturing processes will continue to improve, causing prices to gradually decrease.

PV conversion efficiencies have increased with commercially available modules that are from 12 to 17 percent efficient, and research laboratory cells demonstrate efficiencies above 34 percent. A well-designed PV system will operate unattended and requires minimum periodic maintenance, which can result in significant labor savings. PV modules on the market today are guaranteed by the manufacturer from 10 to 25 years and should last well over 30 years. PV conversion efficiencies and manufacturing processes will continue to improve, causing prices to gradually decrease, however no dramatic overnight price breakthroughs are expected.