Commercial Solar ROI Calculator 2026: §48E ITC & MACRS
Estimate commercial solar payback in 2026 with the §48E credit, 5-year MACRS depreciation and USDA REAP grants, plus the deadlines to qualify.
Estimate scope & data quality
This tool provides an input-driven estimate. Use the required inputs shown above and review the result limitations below.
- Data quality
- NOT_AVAILABLE
- Result limitation
- Calculator output is not a source-complete customer result.
A tariff credit is distinct from annual savings. If a result is NOT_COMPUTABLE or CONFLICT, it must not be replaced with an estimate or treated as canonical.
How to use this calculator
- Enter the total installed cost of the system from your quote.
- Adjust the system size (kW), your blended commercial electricity rate and local peak sun hours.
- Enter your tax rate for MACRS depreciation (use 0 for nonprofits, churches, schools and governments).
- Set the §48E credit percentage — 30% only if the project meets the 2026–2027 deadlines and requirements, otherwise 0 — and add any USDA REAP or other grant.
- Read the credit, MACRS benefit, net cost, annual savings and simple payback.
Understanding your results
§48E clean electricity investment credit. Business-owned solar can still earn a federal investment credit in 2026 under §48E (the successor to the old §48 ITC). The calculator defaults to 30%, which assumes the project qualifies for the full rate (larger projects must meet prevailing-wage and apprenticeship rules). Under the One Big Beautiful Bill Act (Public Law 119-21), solar must have begun construction by Jul 4, 2026, or be placed in service by Dec 31, 2027, and must satisfy the new foreign-entity-of-concern (FEOC) restrictions on components. Because the Jul 4, 2026 date has passed, a project that had not begun construction by then must be in service by the end of 2027 to qualify. If your project will miss that, set the credit to 0.
Tax-exempt organizations. Nonprofits, churches, schools and state or local governments can still receive §48E as a direct payment through elective pay (§6417) for qualifying projects within the same deadlines. Set the tax rate to 0, since MACRS depreciation gives them no benefit.
MACRS depreciation. Commercial solar is 5-year MACRS property. The depreciable basis is reduced by half of the credit, so with a 30% credit you depreciate 85% of cost. The calculator shows the total tax value of that depreciation (basis × tax rate), not discounted for timing; bonus depreciation, if you elect it, can pull more of it into year one. Example: $150,000 × 85% × 21% = $26,775.
Savings and payback. Annual production = kW × peak sun hours × 365 × 0.82; savings = production × your blended rate, assuming the business uses the power on site. Payback = (cost − credit − MACRS benefit − grants) ÷ annual savings. At the defaults (50 kW, $150,000, 13.97¢/kWh — the US commercial average, EIA July 2026 year-to-date — 4.5 sun hours, 21% tax, 30% credit) that is about $78,200 ÷ $9,430 ≈ 8.3 years; with no credit it is about 12.6 years. Demand charges, export rates and escalating tariffs change the real result.
Commercial electricity rates. Blended commercial rates vary widely by state, rate class and demand charges (see EIA). Use your actual all-in rate from the last 12 months of bills.
This is an estimate, not tax advice; confirm credit eligibility, basis and depreciation with a tax professional.
Frequently asked questions
Direct answers for US homeowners.
Related guides
In-depth articles on sizing, costs, and energy decisions.