GUIDE · FOR UK SOLAR INSTALLERS AND SALES TEAMS · 10 MIN READ

How to Sell Commercial Solar: From Booked Survey to Signed Contract

For UK solar installers and their sales teams: the commercial solar sales process stage by stage, the proposal, objections, follow-up and the mistakes that lose deals.

The commercial solar sales process

Selling solar to a business means more people, more data, a grid connection and usually a formal approval. Commercial deals on Solar Surveys UK typically close in 4 to 8 weeks from first contact, and each stage below is a place a deal can stall.

1. 1

   First call

   Confirm what the business wants, who signs, roughly what it spends on electricity, whether it owns the building and when it could decide. Book the survey with the decision-maker.

2. 2

   Site survey

   Roof, structure, supply, point of connection, shading and consumption, plus a conversation with whoever signs. It is a sales meeting as much as a technical one.

3. 3

   Proposal

   A system designed around the site's real energy data, with the financial case set out so the finance director can check it.

4. 4

   Finance

   Outright purchase, asset finance, leasing or a power purchase agreement, depending on the customer's cash and appetite for owning the asset.

5. 5

   Board or FD sign-off

   Someone other than the person you met often approves the spend, so the proposal has to work when forwarded without you.

6. 6

   Grid connection (G99)

   Nearly every commercial system needs a G99 application. Start it early so the connection offer lands alongside the decision.

7. 7

   Contract

   Final design, terms, payment stages, installation window and what happens if the connection offer changes the scope.

The stages overlap: start the grid conversation at the survey and put finance in the first proposal, so the customer never waits on you.

Preparing for the survey

The survey is your most important sales meeting. Before you travel:

• Confirm who will be there, and that it includes the person who signs.
• Ask for bills or half-hourly data in advance to sense-check the system size.
• Check whether the business owns or leases the building.
• Check the roof on satellite imagery: material, rooflights, shading.
• Find the likely network operator.
• Know which finance options you can offer.

On site, capture everything you need to write the proposal without going back to the customer. Our commercial solar survey checklist lists what to confirm before, during and after the visit.

Who's in the room and what they care about

Several people usually have a say, each with a different question. The proposal has to answer all of them, because it is passed around after you leave.

Ask early who else approves it. If it goes to a board, find out when it meets and what format it wants. A proposal written for the board can be forwarded without rewriting.

Building the commercial solar proposal

It will be read by people who check numbers for a living, so credibility beats a headline figure. Include:

• A plain-English summary page: system size, what it does for the site, the investment and finance options.
• The energy data used (half-hourly data or bills) and the period it covers.
• The design: layout, inverters, any battery, and why it is sized that way.
• Estimated generation and how it was modelled, with the assumptions written down.
• Self-consumption versus export, including any export limit.
• The financial case with the method shown: tariff assumed, how payback was worked out and what changes it.
• Finance options side by side.
• The grid connection position: G99 status and what the connection offer could change.
• Warranties, maintenance, monitoring and insurance.
• Next steps and the dates that matter.

On payback, show the method, not just the answer. The tariff, when the site uses power, how much generation it uses itself and what it exports all change the result. A finance director who can follow and adjust your workings will trust them; one who finds an unexplained number will doubt the rest.

On finance, some customers want to buy outright, others prefer asset finance or a lease to spread the cost, and some only consider a power purchase agreement, where a third party owns the system and the business buys the electricity. More than one option keeps the conversation going when the answer is "we don't have the capital".

Objections and honest answers

Most objections are real business concerns, not stalling. Answer them honestly, with the customer's own information.

For the grid connection in detail (G98 vs G99, the forms, the DNO steps, export limitation and timescales) see our guide to the G99 application for commercial solar.

Follow-up after the survey

Deals are won or lost in the weeks after the survey. Each follow-up should give the customer something useful, not just ask if they have decided.

Log every contact, question and agreed next step in your CRM; with several people involved, the deal often goes to whoever remembers what each asked for.

Mistakes that lose commercial deals

• Surveying without the person who signs, so you sell twice.
• Proposals built on guessed consumption.
• Overselling the financial case: one optimistic assumption undermines the rest.
• Raising the lease, the roof or the grid connection after the proposal.
• Emailing a proposal and waiting.
• Offering only one way to pay.
• No agreed decision date.
• Giving every enquiry the same time, whether or not anyone there can sign.

How lead quality changes your close rate

No sales process closes a site where nobody can sign, the business doesn't control the roof or there is no real interest, and each one costs a survey day. Your close rate depends on how many surveys start with the basics in place:

• The decision-maker is confirmed and at the survey.
• Roof ownership is known before you travel.
• Energy consumption is known, so the size is roughly right.
• There is genuine intent, not just curiosity.

That is how Solar Surveys UK qualifies every lead: generated in-house by TNW Marketing's paid media, then qualified by phone by a UK-based team who confirm the decision-maker, roof ownership, energy consumption and intent. You see the system size, property type and how many installers have registered interest before you commit. It's pay per appointment, priced by system size (see how much commercial solar leads cost), and no sit, no pay: if the customer doesn't sit for the survey, you don't pay.

A booked survey gets you in the room. Winning the contract is still down to the survey, the proposal and the follow-up above.

To compare where commercial work can come from, read how to get commercial solar leads. For booked surveys vs form fills, see solar leads UK, and for what we list, see commercial solar leads or how solar survey leads work. Regional pages cover Manchester, London and Birmingham.

Commercial solar sales: FAQ