The installer matters more than the equipment. Most panels sold in the UK are competent, and a good installer with mid-range kit will serve you better than a poor one with premium kit.
MCS is the one that matters, and here is why
MCS is the Microgeneration Certification Scheme It certifies both the products and the companies that install small-scale renewable technology.
The reason to insist on it is financial rather than reputational:
- Without an MCS certificate you cannot claim the Smart Export Guarantee. You will not be paid for the electricity you export. See export payments.
- Without MCS you cannot claim a Boiler Upgrade Scheme grant on a heat pump. See the grant.
That is the whole argument. It is not a badge, it is the thing that unlocks the money.
Check the certification yourself on the MCS website rather than taking a logo on a van at face value. And check the certificate covers the technology you are buying. A company certified for solar PV is not necessarily certified for battery storage or heat pumps.
Consumer codes
Separately from certification, there are consumer codes. The two you will meet in this market are RECC, the Renewable Energy Consumer Code, and HIES. Both are scheme operators under TrustMark, a government-endorsed quality scheme.
What a code gives you, where an installer belongs to one:
- A contract written to a standard, with clear cancellation rights
- Deposit protection, so your money is not simply gone if the company fails
- An independent route to resolve a dispute, short of going to court
We are not going to tell you that membership is compulsory, because the requirements have been changing and we have not been able to confirm the current position with MCS directly. Treat a code as something worth having rather than something an installer must have.
Ask each installer do you belong to a consumer code, and which one? What deposit protection does it give me? What happens to my deposit if you cease trading? And what is the complaints route if we disagree?
Those four answers tell you more than the logo does.
What separates a good installer from an adequate one
- They ask about your electricity usage, not just your roof. The way you use electricity determines what the system is worth.
- They ask about shading and account for it in the output estimate.
- They go up to the roof, or at least look at it properly. A quote produced entirely from aerial imagery is a starting point, not a quote.
- They show their working on the generation estimate.
- They explain the grid connection position without being asked.
- They are clear about what is included: scaffolding, certification, network notification, waste removal, making good.
- They are relaxed about you taking time to decide.
Warning signs
- A price that expires today. Solar is not a category where a genuine discount disappears in an afternoon.
- A deposit of 50% or more. Not standard. See deposits.
- A savings figure with no workings, or one that assumes you use almost everything you generate.
- No mention of shading when you can see a chimney on the roof.
- Reluctance to confirm MCS certification or to say which technologies it covers.
- A price you cannot see in full. Ask for the total cash price, in writing, with everything it includes.
- Pressure to sign at the kitchen table. You have cancellation rights and any decent firm knows it.
- A battery proposed for the loft. Ask how it complies with BS 7671 Amendment 4. See battery siting.
What to check before you sign
- MCS certification, verified, covering the right technologies
- Whether they belong to a consumer code, which one, and what deposit protection it gives you
- Insurance, including public liability and any workmanship warranty
- Who actually does the work. Subcontracting is common and not a problem, but you should know
- Written quote with the system size in kW, the generation estimate and everything included
- Warranty terms for panels, inverter, battery and workmanship, separately
- What happens if the network operator restricts the system
Get comparable quotes
The point of getting several quotes is not to find the cheapest. It is to find out what the range looks like and to notice what one installer has spotted that the others have not.
Tell each of them the same things. Take the questions list to every appointment.