Understanding the 3% scenario
Why 3% is the reference rate
Historical US residential electricity rates have risen roughly 2 to 3% a year on average over the long term, making 3% a reasonable middle assumption for planning purposes. This tool gives that specific scenario a dedicated, complete year-by-year reference without needing to select a rate elsewhere first. The US Energy Information Administration's electricity data show how retail rates have moved, which is the starting point for any savings estimate.
What the full table shows
Starting at $1,800 in year one, annual savings climb steadily each year, reaching $2,349 by year 10 and $3,659 by year 25. The cumulative 25 year total comes to $65,627, compared to $45,000 if savings had stayed flat the whole time, a meaningful $20,627 difference attributable entirely to rate growth. If you have not sized the system yet, start with the system size by annual kwh usage and bring its kilowatt figure back here.
How this compares to the general projection tool
The underlying math is identical to the rate inflation projection tool, this version simply locks the rate at 3% and shows every single year rather than selected milestones, making it a fast reference for the most commonly used assumption. Output varies by roof and weather, and the output comparison 25 year projection tool shows what your site should produce in a typical year.
Checking other scenarios too
Actual future rates could run higher or lower than 3%. See the 5% rate inflation calculator or 7% rate inflation calculator for higher-growth scenarios, or the sensitivity calculator to see all the scenarios side by side at once.