What to Look for in a Solar Supplier (Beyond the Unit Price)

Any installer can pull a price list from three distributors before smoko. Email a rep, get a spreadsheet back, sort by dollars per watt, done. That is the easy part, and because it is easy, it is where most operators stop. They pick the supplier with the sharpest number on a tier-1 panel and call it a procurement decision.

I have made that mistake, and I have watched plenty of good operators make it too. The unit price is the one thing on a supplier that is trivial to compare, which is exactly why it tells you the least about whether that supplier will actually make you money.

Here is the uncomfortable truth. A panel that is forty cents a watt cheaper does nothing for you if it turns up three days late and you have to stand a crew down. The discount evaporates the moment you rebook two sparkies and push a customer’s install into next week. The real money in a supplier relationship lives in the things that never appear on the price list.

Why the cheapest line item is rarely the cheapest supplier

Think about what a price list actually contains. It is a snapshot of one number, on one day, for stock that may or may not be in the warehouse. It says nothing about what happens when things go wrong, and in this trade things go wrong constantly.

Your margin on a job is not set when you buy the gear. It is set across the whole chain: how fast you quoted, whether the stock arrived on the booked day, whether the inverter commissioned without a support call, and how long your cash sat tied up before the job was paid. A supplier touches most of those points. A cheap supplier who is unreliable on any one of them quietly drains the margin you thought you locked in at purchase.

So when I size up a supplier now, price is one input among many. Below is the checklist I run, and I would not make anyone a preferred supplier until they have cleared at least five of these.

1. Freight reliability

This is the one that costs you the most when it fails, because a late delivery does not just delay one thing, it cascades. A crew booked for Monday that has no panels on site Monday morning is a write-off day you cannot easily claw back.

Ask the hard questions before you commit. What are the genuine lead times, not the best-case ones? How consistent are the delivery windows? And critically, who carries the risk when stock turns up damaged? A pallet of cracked glass is a problem either way, but it is a very different problem if the supplier wears it and re-ships overnight versus if you are stuck arguing about freight insurance while your customer waits.

2. Stock reliability

Lead times mean nothing if the supplier substitutes products at the last minute. There is a specific operational pain here that anyone who has run installs knows: you brief a crew on one inverter, write the quote and the paperwork around it, and a different unit shows up on the truck.

Now your install instructions are wrong, your compliance paperwork may need redoing, and your sparky is improvising on a roof. A supplier who consistently has what they said they had is worth real money, even at a slightly higher number. Stock you can rely on is a feature, not a given.

3. Tech support you can actually reach

When you have a commissioning fault on site, with a customer watching and a crew on the clock, the question is brutally simple: can you get a human on the phone right now? Some distributors run genuinely good tier-1 phone support with techs who know the products. Others route everything through an email queue that answers in 48 hours, which is useless when the van is idling in the driveway.

Before you sign on, find out the support hours and whether the support is Australia-based and product-trained. Test it. Ring the support line with a real pre-sales technical question before you ever place an order, and see what happens. How a supplier answers the phone when you are not yet a customer tells you how they will answer when you are one with a problem.

4. Credit terms and the cash flow squeeze

This is the dimension most installers under-weight, and it is pure working capital. Whether a supplier offers payment on net 30, net 60, or demands payment upfront changes how much of your own cash is fronting the business at any moment. At volume, the difference is enormous.

Late payment and tight terms are a known killer of small businesses, which is part of why the Commonwealth runs the Payment Times Reporting Scheme to push large businesses to pay smaller suppliers faster (Payment Times Reporting Scheme, n.d.). The cash flow timing here is not academic. The Australian Taxation Office’s own guidance on managing business cash flow makes the point that the gap between paying for stock and being paid for the job is where many otherwise profitable businesses come unstuck (Australian Taxation Office, n.d.).

Extended terms are negotiable and rarely advertised. Long-standing accounts in good standing can often get terms a casual buyer never sees. Ask. The worst they say is no.

5. Warranty handling, the part that bites later

Every panel and inverter line carries a manufacturer warranty, but the warranty document is not the thing that matters to your operation. What actually counts is how a supplier behaves when something fails in the field: how quickly they process a return, who wears the cost of the replacement unit, and whether you’re stuck chasing paperwork for six weeks while your customer’s system sits offline (Claimlane, 2024).

This feeds straight into your own warranty response time, and your reputation rides on it. Remember that under the Australian Consumer Law your customer also has consumer guarantee rights that sit on top of any manufacturer warranty, so a slow supplier returns process does not pause your obligations to the person who paid you (Australian Competition and Consumer Commission, n.d.). A supplier with a fast, sane returns process is protecting your customer relationship as much as their own.

It is also worth checking that the products a supplier carries are on the approved lists, because compliance and warranty both depend on it. The Clean Energy Council maintains the lists of approved modules and inverters that installs need to use to stay eligible (Clean Energy Council, n.d.).

6. Training and genuine product knowledge

There is a real difference between a rep who is an order-taker and a rep who actually knows the gear. Does the supplier run installer training sessions? Can you call someone for a pre-sales technical question and get a useful answer rather than a brochure?

The best supplier relationships I have had always included at least one person I could ring to sanity-check a product choice before I quoted it. That access saves you from speccing the wrong inverter for a tricky site, which is a far more expensive mistake than paying a few cents more per watt.

7. Relationship continuity

Do you have a dedicated account rep, or does every call start from scratch with whoever picks up? Continuity is not a soft nicety. The operators who invest in a real relationship get things the casual buyer never does: stock allocations held back during a squeeze, early warning when a line is going end-of-life, and pre-release pricing.

That said, continuity through one person is also a risk if you let it become your only channel, which is the flip side worth keeping in mind. I have written before about why you should never let yourself depend on a single distributor in why I stopped relying on a single solar supplier. The goal is a deep relationship with at least two qualified suppliers, not a single point of failure you have dressed up as loyalty.

The compliance thread running through all of it

One more reason supplier quality matters: a chunk of your cash flow is tied to paperwork that depends on the gear being right. STCs are certificates generated from an eligible system’s deemed output, assigned to you in exchange for passing the value on to the customer as a point-of-sale discount. They only come into existence cleanly when the install uses approved products and the documentation is in order (Clean Energy Regulator, n.d.).

Note: The original paragraph is cut off mid-sentence at “wh”. I’ve rewritten up to that point faithfully. Send the full paragraph and I’ll complete the rewrite.en the install uses approved products and the documentation is in order (Clean Energy Regulator, n.d.). STCs are not a government rebate, they are tradeable certificates that liable entities must surrender, and their price floats on the open market, though they can also be sold through the Clean Energy Regulator’s STC Clearing House at a fixed price of $40 per certificate. A supplier who ships the wrong or non-approved product does not just cost you a rebook, they can jam up the certificate side of the job too.

How to actually run this

Do not try to score a supplier on all seven dimensions in one sitting. Build it into how you already work. Test the support line before you order. Push on credit terms once you have a few clean orders behind you. Watch how the first damaged-freight claim gets handled, because that one event tells you more than any sales pitch.

The point is to stop letting a single number on a spreadsheet make a decision that touches your whole operation. Price is real and it matters. It is just the easiest factor to compare and the worst one to decide on alone.

This kind of evaluation, the supplier scorecard, the credit terms, the lead times, the warranty turnaround, is exactly the operational detail that ends up scattered across emails, spreadsheets and someone’s memory. It is part of why I am building CurrentFlow: an all-in-one platform for Australian solar install businesses, designed so the procurement and job side of the business finally live in one place instead of five. It is not live yet, but if that is a problem you feel every week, you can join the waitlist.

References

Australian Competition and Consumer Commission. (n.d.). Consumer rights and guarantees. https://www.accc.gov.au

Australian Taxation Office. (n.d.). Managing your small business cash flow. https://www.ato.gov.au

business.gov.au. (n.d.). Payment Times Reporting Scheme and invoicing. https://business.gov.au

Clean Energy Council. (n.d.). Approved products: modules and inverters. https://www.cleanenergycouncil.org.au

Clean Energy Regulator. (n.d.). Small-scale Technology Certificates and the Small-scale Renewable Energy Scheme. https://www.cleanenergyregulator.gov.au

FAQ

Is the cheapest solar distributor always the most expensive in the long run?

Not always, but the headline price tells you very little on its own. A sharp unit price gets wiped out fast by a single late delivery, a last-minute product substitution, or a warranty return that drags for six weeks. Judge a supplier on freight reliability, stock consistency, support, credit terms and warranty handling, then weigh price against all of it.

What credit terms should I expect from a solar supplier?

It varies by supplier and by how established your account is. Upfront payment, net 30 and net 60 are all common. Extended terms are usually negotiable for accounts with a clean payment history, and they are rarely advertised, so it is worth asking directly. The longer your terms, the less of your own working capital is tied up fronting stock before a job is paid.

How do I test a supplier’s tech support before committing?

Ring the support line with a genuine pre-sales technical question before you place any order. Note whether you reach a product-trained human or an email queue, what the hours are, and whether support is Australia-based. How they treat a prospect is a fair preview of how they will treat you mid-fault with a crew on site.

Are STCs a rebate I get from my supplier?

No. STCs are tradeable certificates created from an eligible system’s deemed generation, which the customer typically assigns to you in exchange for an up-front discount, which is why it feels like a rebate to them. They are surrendered by liable entities under the Renewable Energy Target, and their price floats with the market. Using approved products and keeping clean documentation is what lets the certificates be created without hold-ups (Clean Energy Regulator, n.d.).

How many preferred suppliers should I have?

At least two that can each cover your core product set. One supplier is a single point of failure for stock, pricing leverage and your rep walking out the door. Two qualified preferred suppliers gives you a second door to knock on without spreading your volume so thin that you lose standing with either.