How to choose a solar company — a checklist

Judge the questions, not the pitch

The most reliable signal is what a company asks you before proposing anything. An installer who quotes a system size from a phone call has skipped every input that determines whether the system will perform.

Expect to be asked about: your billing history or meter readings, your connection phase, the daily shape of your consumption, your roof’s orientation and shading, and what must keep running during an outage.

The checklist

Design and engineering

• Will they carry out a site survey before quoting?
• Can they show a single-line diagram for a comparable installation?
• How is earthing designed and tested?
• How is protection selected and coordinated?

Scope and documentation

• Is the scope written down, item by item?
• Is remedial electrical work included or excluded?
• Is net metering application support included?
• What documentation is handed over at completion?

Equipment

• Exactly which modules and inverter, by make and model?
• What are the warranty terms, and how is a claim actually made in Pakistan?

After installation

• Who maintains the system, and at what interval?
• How would underperformance be detected?
• What is the response if output is below expectation?

Answers that should give you pause

• A price before a site visit.
• A system size derived from your bill alone, with no discussion of consumption shape.
• Reluctance to name specific equipment.
• A quotation substantially below others, without a scope difference that explains it.
• No mention of earthing, protection, or the condition of your existing installation.
• Pressure to sign before the design is documented.

Check that the business is a business

Before the engineering questions, three checks cost nothing and remove most of the risk:

• A physical address you can visit, not only a phone number and a social media page.
• A registered entity, with documentation you can be shown on request, and payments made to a company account rather than a personal one.
• Continuity — how long the business has operated under this name, and whether the people quoting you are employees or subcontractors who will not be seen again.

None of this proves engineering quality. All of it predicts whether anyone will answer in year four, which is when you will actually need them.

What a proper site survey includes

If a survey happens at all, it should produce more than a photograph of the roof. Expect the surveyor to:

• Measure or verify usable, unshaded roof area, allowing for parapets, tanks and stairwells.
• Assess shading through the day and across seasons, not just at the moment of the visit.
• Check the roof structure and how a mounting structure would be fixed and loaded.
• Plan the cable route from array to inverter to board, and where the inverter will live.
• Open and inspect the distribution board, protection and earthing.
• Confirm the connection phase and sanctioned load, particularly where net metering is intended.
• Ask what must keep running during an outage, if backup is in scope.

A survey that skips the board is not a survey of the electrical installation. It is a look at a roof.

Reading the proposal

Five things separate a proposal from a price:

1. A named scope, item by item, including exclusions.
2. Named equipment — make, model and quantity, not “Tier-1 panels”.
3. A design, or at minimum a single-line diagram of what is proposed.
4. A schedule, with the stages that depend on the utility identified as such.
5. Terms — payment stages, warranty on workmanship, and what happens if output disappoints.

Warranty, guarantee, and what each is worth

The words are used loosely, so ask which one is being offered:

• Manufacturer product warranty — from the manufacturer, on the item, claimed through their local channel. Ask how a claim is actually made in this country, and who handles it.
• Manufacturer performance warranty — on module output over time. A different document with different terms.
• Installer workmanship warranty — the installer’s own commitment on the installation. Its value depends entirely on the installer still existing.
• A “guarantee” of savings or generation — treat with caution. Output depends on weather and on your consumption; anyone guaranteeing a rupee figure is guaranteeing something they do not control.

Payment terms that protect both sides

Reasonable terms tie money to deliverables: a deposit on order, a stage on delivery of equipment to site, a stage on installation, and a final payment on commissioning and handover of documentation. Full payment before equipment arrives leaves you with no leverage and the installer with no incentive to finish quickly.

Ask for equipment serial numbers at delivery. It is a small thing that makes substitution difficult.

The question that predicts everything

Ask: “Who maintains this, and what does that cost?”

An installer who has thought about the answer has a business model that assumes they will still be here. One who has not is quoting a single transaction, and that is what you will get.

A note on reviews and rankings

Search rankings and review counts reflect marketing activity as much as engineering quality. They are worth checking, but they are not evidence about how a system was designed. Ask for a site visit and judge the questions.