What to Look for in a Microinverter Supplier — And 6 Other Questions B2B Solar Buyers Keep Asking

Quick answers to the questions that keep coming up

I review inverter specs, distributor quotes, and warranty language before anything gets signed — roughly 200 line items a year across residential and small commercial projects. These are the questions I get asked most, usually in the same order, and usually right before someone's about to sign a PO they'll regret. Here's what I tell them.

What should I actually look for in a microinverter supplier?

The datasheet is the last thing I check. What matters is warranty transferability when the homeowner sells in year 7, disclosed annualized failure rates (not "<1%" marketing copy), rapid shutdown compliance that's actually certifiable on site, and — this is the big one — who answers the phone when a unit fails in year 6. I ran a blind comparison of two suppliers' RMA processes last year: same failure rate claimed, wildly different timelines. One shipped a replacement in 4 days. The other took 11 (and blamed "logistics"). Failure response is the real product. The spec sheet is just the entry fee.

SolarEdge shipped 12.6 GW of inverters in 2023 — does that number matter to a distributor?

It matters, but not for the reason most people think. Scale is a proxy for three things a distributor actually cares about: depth of spare-parts inventory, solvency over a 12–25 year warranty horizon, and whether field service exists in your region. A 12.6 GW shipment year (verify current figures — SolarEdge publishes them in quarterly filings, and 2024 numbers are already out) tells me the company can absorb a bad quarter without disappearing. What it doesn't tell me is how well they support your specific SKU mix. I've seen large vendors with terrible regional coverage and small ones with surgical response. Scale is a floor, not a ceiling.

Hybrid inverter or separate components — which is actually better?

Depends entirely on the application, and anyone who gives you one answer for both residential and C&I is selling something. For residential with storage, a hybrid inverter is usually the right call — one monitoring platform, one warranty contact, one firmware update cycle. For commercial and industrial, separation often wins: you can swap an inverter without touching the storage system, you're not locked into one vendor's battery ecosystem, and downtime on one leg doesn't kill the whole site. The mistake I see is people buying hybrid because it sounds more integrated. Integration is only a benefit when you actually want the components integrated.

What do I need to know about the SolarEdge EV charger before I spec it?

The honest answer: its value depends on whether you're already in the SolarEdge ecosystem. The charger itself is competent hardware. What people pay for is the single-pane monitoring — inverter, storage, and EV charging all on one dashboard, one app, one support line. If you're not running SolarEdge inverters, you're paying ecosystem pricing for standalone-charger performance. I'd rather tell a customer that plainly than oversell a compatibility story they'll resent in year 3. There's a version of this sales pitch that works and a version that doesn't — the one that works starts with "here's when this makes sense for you."

How do I vet a PV inverter distributor without wasting three months?

Ask them what they don't stock. A distributor who claims full coverage of the inverter market is either lying or spread so thin they can't negotiate real pricing. The ones worth working with will tell you their sweet spot fast: "We're strong on string inverters up to 100 kW, we don't play in microinverters, and we're honest about lead times." What most people don't realize is that a distributor's stated product breadth is often just a catalog they can order from — not inventory they hold or service they can support. Ask for their last three RMA cases by SKU. Their answer tells you everything.

What's the one question most buyers forget to ask?

"Walk me through what happens when a unit fails in month 14." Not the warranty document. The actual process. Who pays return freight? What's the diagnosis turnaround? Do they ship a replacement first, or wait for the returned unit? I don't have hard data on how many buyers actually ask this — but based on the warranty disputes I've cleaned up over four years, my sense is it's under 20%. That single question filters out about half the vendors I'd otherwise have to say no to later.

Isn't a one-stop shop better than working with specialists?

Not usually, and this one took me a while to accept. For years I assumed a vendor who could do "everything" was more efficient. What I've learned — painfully, on a $40k project that got delayed six weeks — is that "everything" usually means "a bit of everything, well." The vendor who told me "that's not our strength, here's who does it better" earned my trust for the ten things they were great at. I'd rather work with three specialists who each know their limit than one generalist who won't admit theirs. The 'one-stop shop' thinking comes from an era when coordination costs were brutal. Today, with modern logistics and shared monitoring platforms, the coordination tax is much lower — and the cost of a vendor overreaching their competence hasn't gone down at all.

No tidy summary here. If you're evaluating a supplier and they haven't told you what they're not good at yet, keep asking.