Questions to ask a solar installer

You don’t need to be a solar expert to ask useful questions. Take this list to your appointment and ask for the important answers in writing.

About your roof and panels

• Why have you chosen this number of panels for my home?
• Can you show me where they will fit?
• How have you allowed for shade and the direction of my roof?
• How much electricity should the panels make each year, and how will that vary by month?
• Why have you chosen this inverter, which converts the panels’ electricity for use at home?

About the price

• Does the price include VAT, scaffolding and all electrical work?
• Is anything left out or likely to change after the survey?
• What deposit is needed, and how is it protected?
• When are the remaining payments due?

About the savings

• How much of the solar electricity do you expect me to use at home?
• What electricity prices and export rate have you used?
• Have you assumed that electricity prices will rise?
• Have you allowed for upkeep or equipment replacements?
• How would the savings change if I used less solar electricity at home?

If the quote includes a battery

• How much would the same panels cost without it?
• How much electricity can I use from the battery?
• Which appliances can it run at the same time?
• Will it power any part of my home in a power cut?
• How long is the warranty, and what limits apply?
• Does my electricity supplier need to control when it charges?

About installation and aftercare

• Which company will install the system, and can I find it in the MCS directory?
• Who checks planning permission and deals with the local electricity network?
• Who should I contact if the roof leaks, the app stops working or the system develops a fault?
• What certificates, manuals and warranties will I receive?
• What happens to my warranty if your company stops trading?

Before the appointment ends

Ask for a copy of the quote, roof layout, savings estimate and contract. It’s fine to take time to read them and come back with questions.

Use the comparison worksheet to record the answers, then run through the quote checklist before choosing.

If the offer includes funding, use our grant checklist to check the scheme and who is arranging it.