A productive solar consultation starts with a clear picture of how your household uses energy and what you want a system to do. Use this guide to prepare questions, compare proposals, and identify details that need a written answer before you commit.
1. Decide what you want solar to accomplish
Solar can reduce the electricity you buy from the grid, provide backup during some outages, or support future changes such as an electric vehicle. Those goals can require different equipment. A grid-connected solar system may shut down during an outage unless it includes equipment designed to provide backup power. A battery adds storage, but its capacity, output, and wiring determine what it can support.
Before the appointment, write down your priorities. Rank them so an installer can explain tradeoffs instead of treating every feature as essential.
- Lower electricity purchases over time.
- Backup for selected circuits or for more of the home.
- Prepare for a planned EV, heat pump, workshop, or home addition.
- Reduce daytime grid use, evening grid use, or both.
- Keep a portable power station charged for travel or limited emergency use.
Ask: “Given these priorities, what system configuration would you recommend, and what would it not do?” Request the answer in plain language, including assumptions. For example, a proposal may assume that the utility continues to provide power, that the roof remains unobstructed, or that household use stays near its current level.
Bring useful information
Gather recent electric bills if available, ideally covering different seasons. The bill may show monthly energy use, charges, peak demand, or the utility’s rate structure. Bring photos of the roof from the ground, the electrical panel, and equipment locations if convenient and safe; do not climb onto the roof or open electrical equipment to gather them. Note any shading, roof repairs, tree growth, or planned renovation you already know about.
You do not need to interpret every line of a utility bill. Ask the installer which figures they used and whether the design accounts for seasonal variation, fixed charges, and any time-based rates that apply to your account.
2. Ask how the design matches your household energy use
A system estimate should have a traceable connection to your home’s energy use. Ask what consumption data the installer used, what period it covers, and how they estimated production. Solar generation changes with season, weather, roof direction, shading, and equipment. A projected annual total is an estimate, not a guarantee that every bill will disappear.
Useful questions include:
- “How much electricity does your design estimate the system will produce in a typical year, and what assumptions affect that estimate?”
- “How does estimated production compare with my use in each season?”
- “What shade, roof orientation, tilt, or nearby obstruction did you account for?”
- “What happens to production if a tree grows or a roof area becomes shaded?”
- “Which parts of my bill can solar affect, and which charges may remain?”
- “If I add an EV or heat pump, how would that change the design?”
Ask to see the proposed panel layout and an explanation of how each roof area contributes. If you have multiple roof faces, ask whether placing panels on more than one face changes production patterns or equipment needs. If the estimate relies on assumptions you cannot confirm, ask for a revised proposal or a clear note describing the uncertainty.
Compare proposals on the same basis
When comparing installers, line up the same details rather than comparing only a system size or a projected savings figure. The table below is a starting point; ask each company to identify what is included and what remains your responsibility.
| Compare this | Ask for this detail |
|---|---|
| Energy estimate | Annual production estimate and key assumptions |
| Equipment | Panel, inverter, battery, and monitoring models, if included |
| Roof work | Attachment approach, repair scope, and exclusions |
| Electrical work | Panel upgrades, wiring changes, and included permits or utility coordination |
| Price and payment | Itemized total, payment schedule, financing terms, and optional items |
| Ongoing support | Warranty contacts, monitoring access, and service process |
A larger system is not automatically a better fit. Ask why the proposed capacity makes sense for your use, available roof area, and goals. If two estimates differ substantially, ask each installer to explain the difference in design assumptions, equipment, included work, and projected output.
3. Understand backup power and portable power options
If backup matters, define what you want to keep running and for how long. A solar array connected to the grid may be required to stop supplying power during a grid outage for safety and system-design reasons. Ask which specific components allow backup operation and whether the system can recharge its battery from solar during an outage. The answer depends on the equipment and configuration.
List essential loads and their approximate use: refrigerator, lights, internet equipment, medical devices, a well pump, or selected outlets, for example. Do not assume every appliance can run at once. Some equipment has a high starting demand, and heating or cooling appliances can use substantial energy. Ask the installer to show which circuits are backed up, the system’s power limit, usable stored energy, and how the system behaves when demand exceeds its limit.
Ask these questions:
- “Which circuits will work during an outage, and how are they selected?”
- “What is the battery’s usable energy and continuous power rating for this configuration?”
- “Can it handle the startup demand of the equipment I want to run?”
- “Can solar recharge it during an outage, and under what operating conditions?”
- “What happens when the battery is depleted or the system reaches its output limit?”
- “Can I add storage later, and what equipment or wiring would that require?”
Portable power stations can be useful for individual devices, travel, or limited backup, but they are not automatically compatible with a home solar system. Compatibility depends on the station’s charging inputs, voltage and current limits, connector type, and the solar modules’ electrical specifications. Ask the equipment manufacturers or installer to confirm compatibility for the exact models. Do not connect a portable station to home wiring or a solar array through an improvised adapter. Follow the station manufacturer’s instructions, and use only charging configurations it permits.
If backup is not a priority, say so. You can ask for a grid-connected design without storage and request the cost and practical tradeoffs of adding a battery later. That comparison helps distinguish what you need now from an optional feature.
4. Clarify roof, electrical, and installation work
Ask how the installer assessed the roof and what condition they expect it to be in over the system’s service life. Solar equipment is attached to a building, so roof age, material, structure, penetrations, and future repairs matter. If the roof may need replacement soon, discuss whether completing that work before installation would avoid removing and reinstalling the array later. The appropriate timing depends on the roof’s condition and the installer’s assessment.
Have the installer explain:
- Where panels, inverters, batteries, conduit, and disconnects would be placed.
- How roof attachments are selected for your roof type and how penetrations are managed.
- Whether the electrical panel has room and capacity for the proposed design.
- Whether any panel, meter, wiring, or structural work is included or excluded.
- Who arranges permits, inspections, and utility interconnection, and who updates you.
- What access, yard preparation, or temporary power interruptions installation may require.
Ask for a written scope that names subcontracted work, cleanup responsibilities, and the process for addressing unexpected conditions. Clarify who to contact if you notice roof leakage, damaged property, or an equipment problem after installation. Avoid relying on verbal promises about work that affects price, schedule, equipment, or responsibility; request an updated written proposal or contract.
5. Review price, savings estimates, and contract terms
Ask for the total project cost and an itemized list of equipment, labor, optional upgrades, and work that could add cost. If financing is offered, request the full terms in writing: payment schedule, interest or other finance charges, loan length, fees, and any assumptions behind a quoted monthly payment. Compare the cash price and financed total where available. Do not evaluate an offer from a monthly payment alone.
Savings projections depend on more than panel output. They may rely on assumptions about electricity use, utility rates, export credits, fees, equipment performance, financing, or future changes to the utility’s rules. Ask which inputs are guaranteed by contract and which are estimates. Ask to see a scenario with lower production or different household use if you want to understand how sensitive the forecast is. Treat projected savings as uncertain unless the contract clearly states otherwise.
Before signing, look for written answers to these questions:
- What exact equipment models and quantities are included?
- What is the payment schedule, and what events trigger each payment?
- Which conditions could change the scope, price, or installation date?
- What cancellation, change-order, and dispute terms apply under the contract?
- Who owns the system, and who is responsible for maintenance or monitoring?
- What happens if utility approval or another project step is delayed?
Read the complete contract and keep a copy of the proposal, equipment list, drawings, and correspondence. If a term is unclear, ask the installer to explain it in writing before you sign. For contractual, tax, or utility questions that depend on your location or circumstances, verify with the relevant source rather than relying on a sales estimate; this article does not determine eligibility or local requirements.
6. Separate equipment warranties from service promises
A solar project can involve several different warranties and service obligations. Ask who backs each one, how long it applies, what it covers, and how to make a claim. Equipment warranties may come from manufacturers, while workmanship or roof-penetration coverage may come from the installer. A performance estimate is not necessarily a production guarantee.
Request a list covering:
- Panels and inverters, including the manufacturer and warranty contact.
- Batteries and any limits or conditions on use, if included.
- Installation workmanship and roof penetrations.
- Monitoring equipment, software access, and communication requirements.
- Labor, shipping, removal, or reinstallation costs that may not be covered.
Ask what happens if the installer stops operating, who can service the system, and whether another qualified service provider can work on it without affecting coverage. Ask what maintenance the equipment makers recommend, how alerts are handled, and whether monitoring requires an internet connection or subscription. Follow manufacturer instructions for cleaning, inspection, battery care, and shutdown; do not assume that climbing onto the roof or opening equipment is safe or required.
7. Use a simple decision and follow-up process
After the meeting, organize the answers in one place. Mark each item as confirmed in writing, still uncertain, or not relevant to your goals. Send a short follow-up asking for missing details, corrected assumptions, or a revised drawing. Compare proposals only after each installer has had a chance to clarify its scope.
A practical decision checklist:
- Confirm the energy-use data and production assumptions.
- Match the design to your priorities, including whether backup is required.
- Verify the equipment models, roof plan, electrical scope, and exclusions.
- Compare total cost and payment terms, not just monthly figures or projected savings.
- Identify warranty providers, service contacts, monitoring needs, and maintenance instructions.
- Keep the final contract, drawings, warranties, and utility or inspection records together.
If an answer remains vague, ask for a specific example or written calculation. If an installer cannot explain a key assumption, consider obtaining another proposal or an independent review appropriate to the question. A good consultation should leave you with a design you can describe, a clear list of what the system will and will not do, and enough written detail to make a considered decision.