How’s the weather where you live? Is there enough sun for solar? Everyone is excited about the recent announcement that San Francisco is about to take real action on climate change, but the folks at think this is a foggy idea. So, we checked it out. Is San Francisco too foggy for solar?

Solar systems in cooler cities like San Francisco are very productive because solar production is reduced when panels and inverters get too hot. This happens in cities that bake in the sun all the time, and can actually result in slightly lower solar energy production.

While fog figures prominently in our mindset about San Francisco, San Francisco compares quite well with all cities in California for solar production according to the California Solar Initiative’s website. When you take into account an entire year of sun hours, the city as a whole has great solar potential. The days that we really need power, the hot days when the air conditioners crank on, are the days with no fog. That’s when solar systems are producing maximum power.

San Francisco compares well with all cities in California for production according to the California Solar Initiative’s website ( A Sungevity Kit A in San Francisco would only produce 5% less than if it were placed in LA or San Diego, and about the same if it were in a hot fog-less city like Fresno, Bakersfield and Sacramento.

Like we said in a response to Grist’s piece, Germany has the largest solar market in the world and they have the solar potential of Nome, Alaska. Good sunlight hours are determined by many factors.

Bottom line: San Francisco is just one great spot among many for solar, and the city’s new initiative is an amazing step in the right direction.

We hope this information helps clear things up!

Posted by Danny Kennedy

Danny Kennedy co-founded Sungevity and now serves as strategic advisor. He is an internationally recognized opinion leader on climate and energy issues. He is the author of Rooftop Revolution: How Solar Power Can Save Our Economy - and Planet - from Dirty Energy (2012), a book that has been described as the clean energy manifesto for the next greatest generation.