Solar payback
When does solar pay for itself?
Put the install cost against what you spend every year on generator fuel and hookups. The lines cross in your payback year.
Payback
n/a
Enter a solar cost and at least one yearly expense.
- Generator fuel plus hookups, adding up
- Solar cost you entered
How the math works
Each year adds generator gallons per hour × hours × fuel price, plus hookup nights × the fee. The green line is that running total. The dashed line is what you paid for solar. Where green crosses dashed, solar has paid for itself.
It's deliberately simple. It doesn't count generator oil changes, batteries you'd replace either way, or fuel prices moving. If those matter to you, nudge the yearly numbers and watch the year move.