Weather Impacts on Solar Power Systems

This past winter season has been the rainiest I have ever experienced in California. The good news is that the state is no longer in a drought condition. The bad news is that severe weather is occurring around the country. We are likely to continue on this trend: a polar vortex recently hit the Midwest, heavy snows on the east coast, and even Seattle was devastated with big snow storms. 2018 was the 4th hottest year on record globally. On average, the summers are getting hotter and the winters are not as cold. 

But this is a show about energy — particularly solar. Although the output of solar systems can be predicted fairly accurately, weather has the biggest impact on annual energy fluctuations [side note: the biggest monetary fluctuations come from your local utility as they raise electric rates]. Several of our customers were concerned about lower energy output from their solar system in November, December and January. We pointed out that rainy weather — including smoke from wildfires — obscured the sunlight enough to make a noticeable difference in energy output. Even our customers who had battery backup systems contacted us, but for different reasons. Many of them had multiple weather-related blackouts this winter. These customers were delighted that their refrigerators, TVs, lights and heat were all still working even though their power was out. 

While one cannot change the weather (unless your name is Dr. Evil), we can prepare for a changing climate. Please listen up to this week’s Energy Show as we discuss how weather impacts solar power system performance.