The sun is shining, birds are chirping, and solar panels are producing gobs of renewable electricity. It’s a perfect day.

Solar enthusiasts sometimes call spring and early summer the solar harvest. Why is that? For some solar homeowners, this is the time of year when their solar panels produce more electricity than they use, allowing them to store solar electricity “credits” on their bill to use later in the year (like squirrels preparing for winter). Then, they can use these credits during high consumption months, such as the hot late summer months when the air conditioning unit is on full blast.

The solar harvest is an exciting time. It sparks enthusiastic testimonials from solar homeowners:

Wow: BGE is *paying* us $30.37 for the excess power our Sungevity system generated last month. How does your electric bill look?Free quote:

Posted by Shahak Nagiel on Tuesday, May 5, 2015


I haven’t paid electricity in 4 months, Thank you so much!

Posted by Corina Cano Scott on Tuesday, June 23, 2015


A state policy called Net Energy Metering, or NEM, makes this “harvest” possible.

NEM works like rollover minutes on your cell phone bill. The electricity that your solar panels generate that your home doesn’t immediately consume equates to credits on your electricity bill. If you consume less electricity than your panels have generated, or if you haven’t used up the credits on your bill accrued from previous months, the credits roll over to the next month. Despite decreased solar production during the winter, some solar homeowners are able to store so many credits on their bill during the prime “harvest” months that they have nearly zero balance on their electricity bill for the year.

The solar harvest also benefits the neighborhood where solar is installed. When a grid-tied solar home produces more electricity than it’s using, that renewable electricity flows back into the grid and helps to power the homes around them. More renewable energy to go around!

Net Energy Metering isn’t available in every state. Contact your utility to find out what policies exist in your area. The credit rate, and how and when the credit applies varies based on utility.

Posted by Leslye Penticoff

Leslye is the Content and Community Manager for Sungevity. She's also an avid coffee drinker and rock climber, and serves on the Board of Directors at Margination, a nonprofit in Troy, NY.