Is the Solar ROI Calculator a final financial quote?

No. It is a planning tool. Final savings depend on utility rules, installed cost, financing terms, tax eligibility, production, and site-specific design.

Should I include financing costs?

Yes. If you are using a loan, include dealer fees, interest, and term assumptions because financing can materially change payback.

What should I use for annual production?

Use a conservative installer production estimate or a panel estimator result that accounts for roof direction, shade, and system losses.

Interactive solar tool

Solar ROI Calculator

Estimate payback, lifetime savings, and return on investment using production, incentives, utility rates, and maintenance assumptions.

Inputs

ROI assumptions

Model the core financial assumptions behind a solar investment.

Methodology

How this calculator works

The Solar ROI Calculator is designed for early proposal review. It helps you compare project cost, incentives, utility rates, annual production, maintenance, and rate escalation before you rely on an installer payback number.

What the calculator estimates

Simple payback based on net system cost and estimated annual savings.

Lifetime savings across the system life entered in the form.

How incentives reduce the upfront cost used in the payback model.

How maintenance and electricity rate escalation affect long-term value.

Inputs to verify before trusting the result

Cash price and financed price should be separated before entering project cost.

Utility export credit should match the current rate plan, not a generic net metering assumption.

Annual production should come from a conservative production estimate when shade or roof complexity exists.

For deeper context, read the Solar Cost and Payback Guide before comparing installer proposals.

Formula used

Net cost = system cost - eligible incentives.
Year-one savings = annual production x electricity rate - estimated annual maintenance cost.
Payback occurs when cumulative annual savings exceed net cost; ROI compares lifetime net savings against the net cost.

Key inputs defined

Net system cost: The installed price after subtracting incentives you are eligible to claim. Financing fees may change the true cost.
Incentives: Federal, state, utility, or local programs that may reduce the project cost or improve the financial return.
Annual production: The expected yearly solar generation in kilowatt-hours, usually modeled from system size, sunlight, and losses.
Rate escalation: The expected yearly increase in electricity rates. Small changes can materially affect long-term savings.
Lifetime savings: Estimated savings over the analysis period after subtracting the net project cost and recurring maintenance assumptions.

Audit the quote assumptions

Use the cost guide to review quote line items, incentive assumptions, and utility-rate details before making a buying decision.

Review solar cost guide

Pressure-test the financial assumptions

Use the cost hub to check quote assumptions, incentives, utility rates, and payback drivers before choosing a proposal.

Read solar cost guide

How this calculator works

What the calculator estimates

Simple payback based on net system cost and estimated annual savings.

Lifetime savings across the system life entered in the form.

How incentives reduce the upfront cost used in the payback model.

How maintenance and electricity rate escalation affect long-term value.

Inputs to verify before trusting the result

Cash price and financed price should be separated before entering project cost.

Utility export credit should match the current rate plan, not a generic net metering assumption.

Annual production should come from a conservative production estimate when shade or roof complexity exists.

For deeper context, read the Solar Cost and Payback Guide before comparing installer proposals.

Formula used

Net cost = system cost - eligible incentives.
Year-one savings = annual production x electricity rate - estimated annual maintenance cost.
Payback occurs when cumulative annual savings exceed net cost; ROI compares lifetime net savings against the net cost.

Key inputs defined

Net system cost: The installed price after subtracting incentives you are eligible to claim. Financing fees may change the true cost.
Incentives: Federal, state, utility, or local programs that may reduce the project cost or improve the financial return.
Annual production: The expected yearly solar generation in kilowatt-hours, usually modeled from system size, sunlight, and losses.
Rate escalation: The expected yearly increase in electricity rates. Small changes can materially affect long-term savings.
Lifetime savings: Estimated savings over the analysis period after subtracting the net project cost and recurring maintenance assumptions.

Audit the quote assumptions

Use the cost guide to review quote line items, incentive assumptions, and utility-rate details before making a buying decision.

Review solar cost guide

Pressure-test the financial assumptions

Use the cost hub to check quote assumptions, incentives, utility rates, and payback drivers before choosing a proposal.

Read solar cost guide