SEIA, the Solar Energy Industries Association is the US trade association for solar energy and related businesses focused on federal policies that expand both domestic and international markets. The Solar Alliance and SEIA work closely together.

American Solar Energy Society accelerates the development and use of solar and other renewable energy resources through advocacy, education, research and collaboration among professionals, policy-makers and the public. ASES publishes the magazine SOLAR TODAY and sponsors the not-to-be-missed, national Solar Homes Tour.

Vote Solar is our sister organization mobilizing citizens in our targeted states to advocate solar policies. They are a non-profit organization whose mission is to mitigate global warming and increase energy independence by bringing solar energy into the mainstream. They work with state governments to remove regulatory barriers and to lay the necessary groundwork for a solar future.

California Solar Energy Industries Association is composed of manufacturers and installers of solar systems. CAL SEIA members support the widespread adoption of solar thermal and photovoltaic systems by educating consumers, supporting solar legislation and conducting business in a professional and ethical manner.

The Arizona Solar Energy Industries Association (AriSEIA) is a non-profit trade association representing local, national and international solar companies in the Arizona market. The group's focus is on education, professionalism and promotion of public policies that support deployment of solar technologies in Arizona.

The Oregon Solar Energy Industries Association (OSEIA) is a trade organization for solar energy businesses with a solid track record in successfully advocating for solar energy interests to the state legislature and government agencies, managing grants, and managing the NW Solar Expo.

TREIA represents over 300 member companies, organizations, agencies and individuals providing products, services and information in the areas of solar electric generation, solar hot water, large and small-scale wind electric generation, biomass electric generation and liquid renewable fuels, geothermal heating and cooling, geothermal electric generation, and sustainable (green) building design and construction.

The Mid-Atlantic Solar Energy Industries Association (MSEIA) is a non-profit organization consisting of manufacturers, developers, contractors, installers, architects, engineers, consultants and other industry professionals. MSEIA is dedicated to promoting the benefits of renewable energy and to developing a strong local industry able to offer high quality installation and professional services to business and residential customers.

The Florida Solar Energy Industries Association (FlaSEIA), founded in 1977, is a nonprofit professional association of companies involved in the solar energy industry. Members include manufacturers, distributors, contractors, retailers and consultants who provide solar water heating, pool heating and solar electric systems. Research Centers and Utilities also are members.