It’s hardly news that a few states account for the large majority of installed solar in the United States. Lighting the Way: The top ten states that helped drive America’s solar energy boom in 2013 by Environment America reports that these ten states, led by California, hold 87% of the nation’s installed solar electric capacity, and only 26% of the U.S. population.
However, the report presents some of this data in new ways. In terms of per-capita solar installations, Arizona and Hawaii are far ahead of market leader California, with 275 and 243 watts of installed solar per resident at the end of 2013, as opposed to California’s 148 watts. Nevada also comes in with a higher level of penetration, at 161 watts per inhabitant.
For international comparisons, long-time market leader Germany had installed 436 watts of solar per resident at the end of 2013, with Italy in second place at 294 watts. This means that Arizona and Hawaii have reached Western European-levels of solar penetration, and that solar is already a significant contributor to the electricity mix in these states.
Rounding out the top 10 U.S. states are New Jersey, New Mexico, Delaware, Massachusetts, Colorado and North Carolina. That North Carolina made the list also shows that solar is expanding beyond its traditional base in California, the Southwest and the Northeast to other regions, if slowly.
The reason for the success in these states is the same as in Europe. These 10 states … possess strong policies that are enabling increasing numbers of homeowners, businesses, communities and utilities to ‘go solar’, notes the report’s executive summary.
The last segment utilities has been particularly key. In these states, as in the rest of the nation, utility-scale PV makes up the majority of installed capacity. In some of the leading states like Nevada and New Mexico, the residential and commercial solar sectors are tiny.
The report also finds that while the success of solar in the United States has been threatened recently by attacks attributed to fossil fuel interests and electric utilities, many states have re-affirmed and even expanded policy commitments.
While the overall market in the United States is still relatively small on per-capita levels compared to most other developed nations, it is growing rapidly, with 4.8 GW installed in 2013. This growth is particularly dramatic when viewed over the last decade, as installed solar capacities have increased more than 120x from 97 MW in 2003 to more than 12 GW at the end of 2013.