Net Metering Calculator
Estimate your monthly electricity bill when solar panels feed surplus energy back to the grid. Use this when evaluating whether net metering makes solar worthwhile in your area.
About this calculator
Net metering lets solar panel owners sell excess electricity back to the grid, offsetting the cost of power drawn at night or on cloudy days. Your monthly bill depends on whether your solar production exceeds your consumption. If consumption exceeds production, you pay: Bill = (monthlyConsumption − monthlyProduction) × electricityRate + connectionFee. If production exceeds consumption, you earn credits: Bill = connectionFee + (monthlyProduction − monthlyConsumption) × creditRate. The credit rate is often lower than the retail electricity rate, so understanding both rates is essential. The connection fee is a fixed monthly charge most utilities require regardless of solar production.
How to use
Suppose your solar panels produce 600 kWh/month and you consume 800 kWh/month. Your electricity rate is $0.13/kWh and your connection fee is $10/month. Since consumption (800) exceeds production (600), you owe grid power for 200 kWh. Bill = (800 − 600) × $0.13 + $10 = 200 × $0.13 + $10 = $26 + $10 = $36/month. Without solar, the same usage would cost 800 × $0.13 + $10 = $114/month — a saving of $78.
Frequently asked questions
How does net metering credit rate differ from the retail electricity rate?
The retail electricity rate is what you pay per kWh when drawing power from the grid. The net metering credit rate is what your utility pays you for surplus solar energy you export. In many states, the credit rate is lower than the retail rate — sometimes as low as the wholesale rate. This difference significantly affects how quickly your solar investment pays off. Always check your utility's tariff sheet for the exact credit rate before sizing your system.
What happens to unused net metering credits at the end of the month?
Most utilities roll unused credits forward to the next billing period, reducing future bills during low-production months like winter. Some utilities reset annual credits to zero at a set date, paying out remaining balances at a lower wholesale rate. A few states offer true monthly cash payments for surplus production. Understanding your utility's rollover policy is critical when deciding how large a solar system to install.
When is net metering most financially beneficial for solar homeowners?
Net metering is most valuable when the credit rate closely matches the retail electricity rate — called one-to-one net metering. It is also more beneficial for households with high daytime production but significant evening consumption, since the grid effectively acts as a free battery. States with high retail electricity rates amplify the financial benefit further. If your utility has recently reduced credit rates, a battery storage system may be worth evaluating alongside net metering.