The Solar Electric Power Association's (SEPA) fourth annual Utility Solar Rankings report analyzes utility solar electricity markets in the United States, focusing particularly on the top utilities that are driving solar electric power growth. The SEPA Top 10 ranked utilities integrated 56MW of solar electricity capacity in 2010, representing 100% growth over one year.

Among the report's key conclusions:

  • Utility solar electric markets continue to expand rapidly across the country, according to SEPA. About 63% of the new solar capacity came from utilities outside California in 2010, the largest percentage on record. Seven of this year‘s Top 10 Solar MW utilities were from outside of California, and four of the top-ranking utilities were located in the Eastern United States. Solar power is becoming recognized as an important element in the energy supply planning and customer energy management of utilities nationwide.
  • Two new growth trends are changing the profile of solar electric power in the United States: centralized projects and utility ownership. Traditionally, solar markets have relied on distributed photovoltaic (PV) for most new capacity. However, centralized projects are gaining new traction — eight centralized projects greater than 10 MW each were installed in 2010. This included what are now the two largest PV projects in the United States — the 48MW Copper Mountain project in Nevada, with power purchased by Pacific Gas & Electric and the 30MW Cimarron project in New Mexico, purchased by Tri-State Generation & Transmission Cooperative Association. The largest concentrating solar power (CSP) project in nearly 20 years was also installed in 2010. It is a hybrid CSP-natural gas facility owned by Florida Power & Light. Centralized projects totaled 226MW in 2010, up from two projects totaling 46MW the year before.
  • Thirty utilities reported owning 140MW of solar. This utility ownership represents a more than 300% increase over the previous year.

A few years ago, the solar installed at many utilities was dominated by customer-owned, net-metered systems. In 2010, the emphasis had shifted to large, centralized plants and utility-owned projects.

Read the full Utility Solar Rankings report.