How do solar heating systems compare to solar electric?

Currently, there is tremendous interest in solar energy in the United States with apparently a lot more interest in solar electricity than in solar heating. How do the two technologies compare? Typically, installers will talk about BTUs when they talk about solar heating systems. That is unfortunate. The general public doesn’t understand a BTU nor do they care to. They are billed in kilowatt hours or therms or gallons for their energy so why do they want to go back to high school chemistry to learn a new item that has no bearing on their daily life? While the two types of solar energy generate their energy in different ways there is a very simple way to compare the two systems. Both solar heating and solar electric systems can be talked about in terms of their peak energy produced. Solar electric systems are marketed by their peak energy production or the amount of energy produced under ideal circumstances. When a solar electric system is installed it is sized, installed, and quoted based on this peak number. A typical residential installation might run from 2 to 5 KW. In residential applications a solar electric system might run $7 - $10 per watt installed. So, a 4 KW solar electric system would cost $28,000 - $40,000 installed (before any incentives). How does solar heating compare? A solar heating system can (and should) be talked about in the same way in terms of peak energy. A standard system with 2 4’x8’ panels a peak output of 4.1 KW. This same system would typically install for between $5000 - $9,000. A huge difference. The next time you are at a trade show or talking to a potential customer let them know that you can install their 4 KW solar energy system for under $10,000 and let’s see if we can get some of the solar electric people to sit up and take notice.