How your solar system’s annual production affects your utility bill


March 3, 2020 | 4min read

The amount of power your solar system generates will vary by season and by how cloudy it is on any given day. Due to that variation in output, the Freedom Forever 25-year production guarantee is based on your solar system’s annual production. You should expect your system’s output to be lower during the winter and on cloudy, rainy, or snowy days.

How seasons affect your solar system’s annual production

Most of the annual production of power from your solar system is generated from the spring equinox in March to the fall equinox in September. That happens because the sun is shining longer on those days and it’s rays fall more directly upon the Earth. As much as 65% of your solar system’s annual production happens between the spring equinox (around March 21st) and the fall equinox (around September 21st). Thus the system may only produce 35% of its annual production during the fall and winter months.

How seasonal variation affects your utility bill

Since your system will produce the least amount of power during the fall and winter months, you should expect to get the least amount of savings from it during those months. If your system first starts operating begins operation during the fall and winter months, you should expect that you’ll still be paying your utility company for a good portion of the power your home uses.

Conversely, your system may produce more power than you use during the spring and summer months. During those months, if you carefully manage your electrical usage, you may be able to accumulate bill credits that would offset the lower production that you get in the fall and winter if your utility offers net metering. Not all utilities provide net metering, so it’s important for you to find out if your’s does. Some utilities may instead pay a set price for the power you supply to their grid. In that case, you don’t accumulate bill credits.

The true-up bill

Your utility company knows that your system’s output varies by season. That’s why at the end of a 12-month billing cycle, they send you a true-up bill. That bill reconciles all of the energy charges you owe with any bill credits you’ve accumulated. If you’ve produced more than you’ve consumed in that period, you may receive a credit on your bill. Some utility companies may instead simply roll over those credits to your next 12-month billing cycle. Your utility company may provide a running estimate of your true-up bill on your monthly billing statement.

The rates you are charged for power may also fluctuate by season

Many utility companies also charge you for power based on the season. Oftentimes their rates are higher in the summer than they are in the winter. It’s very important for you to find out if your utility company’s rates vary by season because those rates can vary by a lot! For example, below are the rates charged by Arizona’s Salt River Project for their Time-of-Use (TOU) plan.

Winter, November through April: Off-peak hours are from 9 PM to 5 AM at 6.91 cents per kilowatt-hour. On-peak hours are from 5 PM to 9 PM and 5 AM to 9 AM at 9.51 cents per kilowatt-hour weekdays.

Summer, May, June, and September October: Off-peak hours are from 8 PM to 2 PM at, 7.27 cents per kilowatt-hour. On peak hours are from 2 PM to 8 PM at, 20.94 cents per kilowatt-hour weekdays.

Summer peak: July and August: Off-peak hours are from 8 PM to 2 PM at 7.3 cents per kilowatt-hour. On peak hours are from 2 PM to 8 PM at, 24.09 cents per kilowatt-hour weekdays.

As you can see, during the winter their peak rate is 9.51 cents per kilowatt-hour. But at the peak of summer, their peak rate is a whopping 24.09 cents per kilowatt-hour! It’s important to understand know how you are being charged and compensated for power so you can manage your power usage so as to try and avoid surprise high utility bills.

Freedom Forever is ready to help you go solar with confidence any time of the year

No matter what time of the year you choose to go solar, Freedom Forever will help you go solar with confidence thanks to our 25-year production guarantee. We guarantee the annual production of your solar system for a full 25 years. If it falls short due to something that was our fault, we will compensate you for that lost production. The amount of compensation you receive will be shown in your contract with us.

Ready to go solar? Call us at 800-685-1850 or click below to get started.