How to Choose a Solar Installer in 2026: 9 Questions to Ask

The questions

If you ask these nine questions of any installer offering to quote your project, the differences between the serious players and the high-volume box-shifters will become obvious inside ten minutes.

1. Who does the survey?

Look for: a named surveyor with an engineering background. Avoid: "our admin team will book it in".

2. Do you use drone capture?

Look for: yes, with examples. Avoid: "we have done a few" or "we use Google Maps satellite".

3. What inverter brand do you fit?

Look for: one or two tier-1 brands fitted consistently. Avoid: "whatever is in stock" or unfamiliar brands.

4. What battery chemistry?

Look for: LFP exclusively in 2026. Avoid: NMC for new home installs.

5. Can I see your ROI cash model?

Look for: yes, full year-by-year with disclosed assumptions. Avoid: one-line payback claim.

6. Who is my named project manager?

Look for: one named person from contract to commissioning. Avoid: "the team will contact you".

7. What is your MCS registration number?

Look for: provided immediately, lookup-able on mcscertified.com. Avoid: "we have it but cannot find it right now".

8. How is the SEG application handled?

Look for: we register it on your behalf with your chosen supplier. Avoid: "we hand you a certificate, you sort it".

9. What happens at year 11 when the inverter dies?

Look for: we offer a service plan that covers it, or here is the realistic out-of-warranty replacement cost. Avoid: "do not worry, they last forever".