Savings and payback
See a full year-by-year table of how your solar savings grow as utility rates rise, isolated from panel degradation to show rate inflation's effect on its own.
For planning purposes only, not financial or tax advice; confirm figures with a licensed installer or tax professional before making a purchase decision.
How it works
Step 1
Use the result from the solar savings calculator as your starting point.
Step 2
The tool compounds your savings forward at that rate and builds a table showing key years, plus the 25 year total. For a version broken down every single year, see the year by year breakdown tool.
Starting at $1,800 in year one savings with 3% annual rate inflation, year 25 savings reach about $3,659, more than double the starting figure. The 25 year cumulative total comes to about $65,627, compared to $45,000 if savings stayed perfectly flat, a $20,627 uplift from rate growth alone. Utility rates drive the whole savings calculation, and the US Energy Information Administration's electricity data track them state by state.
Separating rate inflation from panel degradation makes it clear which factor is driving your projection. Rate inflation alone always pushes savings up, while degradation alone always pulls them down slightly, as seen in the 25 year lifetime savings calculator. Looking at rate inflation in isolation shows the full upside before any offset from declining panel output. The US Department of Energy's homeowner's guide to going solar walks through the same decision step by step.
Historical US residential electricity rates have risen roughly 2 to 3% a year on average, though specific utilities and years vary meaningfully. 3% works well as a reasonable middle assumption for a long-term projection, while the rate increase sensitivity calculator lets you stress-test a wider range. The production figure behind this estimate comes from the output comparison 25 year projection tool, which models output for your location and roof.
This tool leaves degradation out on purpose, to isolate rate inflation's effect. For the combined view, netting both rate growth and panel degradation against each other, use the 25 year lifetime savings calculator instead. This estimate assumes normal upkeep, and the 25 year degradation curve tool breaks down what that upkeep costs year by year.
Questions
Starting at $1,800 in year one savings with 3% annual rate inflation, year 25 savings reach about $3,659, and the 25 year cumulative total comes to about $65,627, compared to $45,000 if savings stayed flat, a $20,627 uplift from rate growth alone.
Separating the two effects makes it clearer which factor drives your savings trajectory. Rate inflation alone always increases savings, while degradation alone always decreases them, so isolating rate inflation shows the full upside before any offset from declining output.
Historical US residential electricity rates have risen roughly 2 to 3% a year on average, though specific utilities and years vary. 3% is a reasonable middle assumption for a long-term projection.
This tool intentionally leaves it out to isolate rate inflation's effect. For a projection that combines both rate growth and degradation together, see the 25 year lifetime savings calculator, which nets the two factors against each other.
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