A multi-institutional research team of scientists led by the U.S. Department of Energy's Lawrence Berkeley Laboratory (Berkeley Lab), in partnership with Sandia National Laboratories, universities, and appraisers found that home buyers consistently have been willing to pay more for homes with host-owned solar photo-voltaic (PV) energy systems -averaging about $4 per watt of PV installed-across various states, housing and PV markets, and home types. This equates to a premium increase of home value of about $15,000 for a typical PV system.
The solar premium is how much more your home will be worth with a solar panel system as opposed to without one. Here's an example: if your home has a 3.6 kilowatt (kW) solar system (the national average) on its roof, this means you have 3,600 watts of solar power (1kW = 1,000W). LBL says that each watt of solar you have will add approximately $4 to your home's value. This means that, thanks to your 3.6kW solar system, your home should sell for about ($4 x 3,600W =) $16,000 more.
What is surprising about these figures is that they are very close to what you would pay for a brand new solar system today. Our own analysis of prices for 6kW solar systems in California reveals that some of the more expensive systems cost just over $4/W.