Solar is a significant purchase. The market includes excellent installers and companies that cut corners on quality, certification or aftercare. Use this checklist before signing anything.
The most important thing: MCS certification
The Microgeneration Certification Scheme (MCS) is the UK's quality standard for small-scale renewables. For solar, MCS certification means:
- The installer is assessed and approved to a defined technical standard
- Your installation receives an MCS certificate — required for SEG payments
- You're covered by MCS's consumer protection framework
- Government grant schemes (Warm Homes Plan, ECO4) require MCS-registered installation
The check that takes 30 seconds
Other certifications that matter
NICEIC / NAPIT approval
Solar involves significant electrical work. Your installer should hold NICEIC or NAPIT approval — both government-authorised electrical competence bodies. Without one, an electrician cannot legally self-certify the work.
TrustMark
The government's quality scheme for home improvement trades. Independently assessed for workmanship, customer service and trading practices.
HIES (Home Insulation & Energy Systems)
Crucial consumer protection: deposit protection up to £2,500 if the installer goes out of business before completing your install. Solar deposits are paid months in advance, so this matters.
Questions to ask before signing
A reputable installer answers all of these directly and without hesitation:
- Are you MCS-registered — can I look you up on the MCS database?
- Are your electricians NICEIC or NAPIT approved?
- Are you TrustMark and HIES registered?
- What panel and inverter brands will you install?
- What warranties cover the panels, inverter and workmanship?
- Who do I call if something goes wrong after install?
- Will you handle the DNO notification and MCS certificate?
- What happens if there is a delay between signing and installation?
- Can you provide references from recent similar installations?
If an installer is vague, dismissive or pressures you to decide quickly — take that as a signal.
Want a no-pressure quote?
Free survey. Written, MCS-compliant quote. No hard sell. We'll give you time to compare.
Ten red flags when getting a solar quote
- No MCS certification — walk away. There's no legitimate reason for an installer to lack it.
- Unsolicited door-knocking — reputable companies don't cold-call.
- Same-day pressure to sign — a sales tactic, not a sign of a good deal.
- No written quote — verbal quotes aren't enough.
- Vague warranty terms — 'manufacturer's warranty applies' is not sufficient.
- No site survey — shading, roof condition and electrics must be assessed in person.
- Unusually low price — quality components cost money.
- No deposit protection — always check HIES registration before paying.
- Claims of 'free' solar that aren't grants — sometimes a lease where you don't own the panels.
- No aftercare or monitoring support — unclear answers now mean no aftercare later.
What Alliant Energy's certification covers
| Certification | What it means for you |
|---|---|
| MCS | Solar, battery and heat pump installation to national quality standard. Required for SEG and grants. |
| NICEIC | All electrical work carried out and certified by NICEIC-approved electricians. |
| TrustMark | Government-endorsed quality scheme. Independently assessed. |
| HIES | Deposit protection up to £2,500. Consumer code covering sales and aftercare. |
| NAPIT | Additional electrical competence registration. |
Frequently asked questions
How do I check if an installer is MCS-registered?
Search the MCS database at mcscertified.com by company name or postcode. If a company claims certification but isn't listed, ask for their MCS number — a legitimate installer will have it instantly.
What is a reasonable deposit?
Industry standard is 10–25% at order, balance on completion. Be cautious of any installer asking for more than 25% upfront — especially if they're not HIES-registered.
Should I get multiple quotes?
Yes — two or three from MCS-registered installers gives you a clear picture of market pricing and design options. Compare system specs (brand, wattage, inverter, warranties), not just price.
How long should the warranty last?
Minimum: 25-year performance, 12-year product warranty on panels, 5-year on the inverter, 2-year workmanship. Alliant provides a 30-year panel warranty on all domestic installs.
