Solar Savings Calculator
Calculates your monthly dollar savings from solar by multiplying your system's production by your local electricity rate. Ideal for homeowners comparing solar quotes or estimating return before purchase.
About this calculator
Your monthly savings from solar equal the value of the electricity your panels produce, since that energy offsets power you would otherwise buy from the grid. The formula is: Monthly Savings ($) = solarProduction (kWh) × electricityRate ($/kWh). Solar production is the total kilowatt-hours your system generates in a month, which varies by season and location. The electricity rate is your blended cost per kWh from your utility bill — divide your total bill by total kWh consumed to find this rate. If your utility offers net metering, excess production exported to the grid is also credited at this rate, making the formula a reliable savings estimate. Comparing monthly savings to your current bill shows the percentage of your electricity cost offset by solar.
How to use
Example: Your current monthly electricity bill is $150. Your solar system produces 400 kWh per month, and your electricity rate is $0.14/kWh. Step 1 — Enter Monthly Solar Production: 400 kWh. Step 2 — Enter Electricity Rate: $0.14/kWh. Step 3 — The calculator computes: 400 × 0.14 = $56.00 in monthly savings. Step 4 — Compare to your $150 bill: solar offsets about 37% of your electricity cost. To increase savings, you would need more panels or a more efficient system to raise monthly production closer to your full consumption of approximately 1,071 kWh (150 ÷ 0.14).
Frequently asked questions
How do I find my electricity rate to use in the solar savings calculator?
Your electricity rate (cost per kWh) appears on your utility bill, usually labelled 'energy charge' or 'rate per kWh.' If you only see a total amount and total kWh used, divide the total bill amount by total kWh to get your blended rate. Rates in the U.S. typically range from $0.09 to $0.30/kWh depending on your state and provider. Using the blended rate is the simplest approach; some advanced analyses use time-of-use (TOU) rates if your utility charges more during peak hours.
What is net metering and how does it affect my solar savings?
Net metering is a billing arrangement where your utility credits you for excess solar electricity you export to the grid. When your panels produce more than you consume (e.g., on sunny afternoons), the surplus flows to the grid and your meter runs backwards, earning credits at the retail electricity rate. These credits offset consumption at night or on cloudy days. Under full retail net metering, the savings formula in this calculator accurately reflects your total benefit. Some utilities offer lower 'avoided cost' rates for exports, which would reduce actual savings below the calculator's estimate.
Why do my actual solar savings differ from the calculator estimate?
Several real-world factors can cause a gap between estimated and actual savings. Seasonal variation means production is higher in summer and lower in winter, so a monthly estimate based on annual averages will be off in any given month. Panel degradation of roughly 0.5% per year gradually reduces output over time. Utility rate changes — either increases (which boost savings) or shifts to demand charges — alter the value of your production. Finally, changes in your household consumption, such as adding an electric vehicle, affect how much solar offsets your bill.