Due to concerns about future energy supplies and environmental concerns, California has made a significant commitment to transforming the energy markets to include significant amounts of solar energy generation. Some examples of the markets for solar include:

• utility scale generation
• distributed generation
• on-site generation

Utility Scale Generation. Large projects that use solar thermal or photovoltaic systems that generate electricity which is fed into the State’s transmission system

Distributed Generation. Medium sized projects that use solar thermal or photovoltaic systems that generate electricity which is fed into the local utility’s transmission system. Some of these systems also provide thermal heating, cooling, and water heating for industrial or process use.

On-site Generation. Projects that are designed to meet the energy needs of the site. These can be either solar thermal or photovoltaic systems. Solar thermal is used to provide water heating, space heating, or cooling. Typical solar thermal systems have energy storage on site. Solar electric systems use photovoltaic technologies to generate electricity. The solar electric systems are connected to the transmission system and allow electricity that is not used on site to ‘run the meter backward’ and accrue credits for the site owner that can be used when the solar electric system is not generating energy (i.e., at night or on cloudy days).

A typical home would have a 40 square foot solar water heating panel and a 400 square foot array of solar electric modules (these numbers will vary based on on-site energy use.

CALSEIA and a related organization, ASPV, commissioned economic analyses on the value of on-site solar electric and solar thermal technologies. Graphs showing the value to California for these technologies are shown below.

Credit: ASPV, 2005