Why questions matter more than answers
Solar installation is a long-term decision involving a large purchase, work on your roof and often a multi-year contract. Quotes can look similar yet rest on very different assumptions. This article does not tell you whether solar is a good idea for you, because that depends on your location, home, electricity prices and local rules. It offers questions that help you compare offers and avoid surprises. The broader context is the wider world of clean energy tech, of which solar is one part.
About your roof and site
- Is my roof suitable? Orientation, tilt, shading and available space all affect output. In the northern hemisphere, panels generally perform best facing toward the equator, but a good installer will assess your specific site instead of relying on rules of thumb.
- What condition is the roof in? Panels can last for many years, so an old roof might need replacing first, or panels may need to be removed later. Ask what that would cost and how it would be handled.
- Does shading change through the year? Trees grow, and nearby buildings can change. Ask whether the design accounts for shading and how it affects output.
- Will I need permits or approval? Local authorities, utilities, homeowners’ associations and landlords may all have a say. Ask who handles the paperwork and who is responsible if approval is delayed or denied.
About the system
- How big is the system, and why? Sizes are usually given in kilowatts. Ask how the installer chose it and what annual electricity production in kilowatt-hours they estimate. Request the assumptions behind the estimate, such as weather data and losses.
- What equipment is included? This includes panels, an inverter, mounting and wiring. Ask about each part’s warranty. Panel warranties are often long, but inverters commonly have shorter ones, so ask about the cost of replacing an inverter.
- Is a battery included or planned? If you might add storage later, the system should be designed with that in mind. Storage is a separate decision, and home batteries have their own costs and limits.
- Can I monitor production? Many systems include an app or display. Combined with data from smart meters, this lets you compare production with consumption.
About money
- What is the total cost, and what is included? Ask for a written, itemized figure covering equipment, labor, permits, grid connection and any required electrical upgrades.
- How will I pay? Options may include cash, a loan, a lease or a power purchase agreement. These work very differently. With leases or agreements, you may not own the system, payments may rise over time and the arrangement may need to be transferred if you sell the home. Read the terms closely.
- What incentives apply? Tax credits, rebates and similar programs vary by location, can change or end, and may have eligibility rules. Confirm the details independently and do not assume the salesperson’s summary is complete.
- How does my utility credit extra production? Some places pay full retail price for exported power, some pay a lower rate and some offer none. Rules also change over time. This single factor can strongly affect value.
Payback, with hypothetical numbers
Payback is how long it takes for savings to repay the cost. A basic calculation divides the net cost by the yearly savings. As a made-up example, suppose a system costs 12,000 after incentives and reduces bills by 1,000 per year. Then 12,000 ÷ 1,000 = 12 years. If savings were 800, it would be 15 years. If electricity prices rise, payback could be shorter, and if they fall, longer.
This is oversimplified. It ignores financing costs, inverter replacement, panel degradation, changing rules and what else the money could have done. So ask the installer to show their estimate of savings, the assumptions and a range of outcomes, and be skeptical of any single promised figure. Savings are never guaranteed.
About upkeep and the future
- What maintenance is needed? Panels have no moving parts and often need little more than occasional inspection, and cleaning in some dusty or leafy settings. Ask what the installer recommends and what your warranty requires.
- What happens if something fails? Ask who services the system, how quickly, and what happens if the installation company closes. Warranties are only as good as the company behind them.
- How does production change over time? Output typically declines slowly with age. Ask for the expected rate.
- What if I move? Ask how the system affects a home sale and whether contracts can be transferred.
- What happens at end of life? Responsible disposal is a legitimate question; proper e-waste recycling for panels and batteries is still developing in many places.
About the company
- Is the installer licensed and insured? Check credentials with the relevant local authority.
- Can I see references and previous installations? Contact a few past customers if possible.
- How many quotes have I gathered? Three is a common suggestion. Compare assumptions, not just totals.
Be careful with pressure
Be wary of door-to-door pressure, deadlines said to expire today, and promises such as free electricity or guaranteed savings. A reputable offer will survive a few days of consideration. Read every document before signing, ask about cancellation rights and, if anything is unclear, consider asking an independent professional to review the contract.
Solar can be a reasonable choice for some homes and a poor fit for others. Good questions bring that difference into view.