What determines whether solar fits your home?
The answer depends on several connected facts—not a single nationwide savings percentage. Begin with your annual electricity use, utility rate structure, roof condition, shade, orientation, available area, expected time in the home and how you plan to pay.
Electricity use and future loads
Use at least 12 months of bills when possible. Then consider upcoming loads such as an EV, heat pump, electric water heater or home addition. Oversizing without a reason can be expensive; undersizing can leave expected future use uncovered.
Roof and site conditions
A roof near the end of its life may need work before panels are installed. Shade, multiple roof planes, local wind or snow requirements, main-panel capacity and utility interconnection rules can all change the design and price.
Compare the proposal in layers
| Layer | What to ask for | Why it matters |
|---|---|---|
| System | DC size, panel count, inverter, battery | Defines the equipment being sold |
| Production | Year-one kWh and degradation assumption | Drives the savings model |
| Price | Cash price and price per watt | Separates project value from financing |
| Financing | APR, fees, term, prepayment terms | A low payment can hide a high total cost |
| Responsibility | Installer, subcontractor, service contact | Clarifies who performs and supports the work |
Do not let a proposal assume that the former Residential Clean Energy Credit still applies to new expenditures after December 31, 2025. Verify current federal information directly with the IRS and confirm state, local and utility programs separately.
Before you sign
- Compare at least the equipment, scope, cash price and assumptions—not only monthly payments.
- Confirm roof work, panel upgrades, trenching, permitting and interconnection responsibilities in writing.
- Ask who provides workmanship service if the salesperson or installer leaves the market.
- Read escalation clauses, early termination terms, liens or UCC filings, transfer requirements and production guarantees carefully.
- Keep the proposal, contract, warranty sheets and financing documents together.