Most procurement teams evaluate First Solar panels in the wrong order. They open a photovoltaic module catalog, see lower efficiency numbers than the latest crystalline module, and move on. Or they see the price and say “that’s for projects with money to burn.” I think both reactions miss the point.
I’ve spent nine years in solar module procurement, and for the last four, I’ve specialized in orders that can’t wait. In my role coordinating expedited module supply for utility buyers, I’ve handled more than 200 rush orders. So when someone asks “are First Solar panels good?”, I answer differently than you’d expect: “good enough to show up, and wrong for the wrong project.” That’s not a marketing dodge. It’s how you should evaluate any module manufacturer.
And if you’ve ever typed “First Solar solar panels” into a search box, you probably noticed the lineup is narrow. That’s by design: Series 6 and Series 7, both thin-film cadmium telluride. It’s not a catalog of fifty SKUs. It’s a focused product line for utility-scale buyers.
The wrong question: “Which solar panel is best?”
Nobody asks “which forklift is best?” without first asking “what load, what floor, what shift?” Solar panels should work the same way. “Best” without a project context is meaningless. Yet almost every RFP I review says “we want high-efficiency PV modules” without saying what the site conditions are. Here’s the thing: nameplate efficiency is the least useful number in a photovoltaic module catalog. It tells you how one module compares to another at standard test temperatures. It doesn’t tell you how it behaves at 3 p.m. in July in Phoenix. It doesn’t tell you whether the module will be available when the transformer has already landed and the crew is standing by.
Start with delivery risk, not efficiency specs
When I’m triaging a rush order, my first question is never “what’s the module efficiency?” It’s “where is the factory, and what’s the realistic lead time?” A module can look excellent on paper and be completely worthless to you if it’s sitting on a ship outside a congested port.
I learned this in March 2024. A utility client called on a Thursday; their original module supplier had just notified them of a ten-week delay. That put the whole commissioning date at risk. We quoted seven manufacturers. Only two could deliver inside the window. One was First Solar, using U.S.-manufactured modules. The other was a crystalline module importer, but only if we accepted a smaller allocation and paid for air freight. We went with First Solar. The modules arrived six weeks later. So glad we checked lead time before price. Almost signed with the importer because the per-watt cost was slightly lower. That would have been false economy.
Oh, and I should add that we had already built a two-week buffer into the civil schedule. That made the six-week delivery comfortable instead of heroic. If we had waited another week to evaluate manufacturers, even First Solar would have been tight.
What I actually check when evaluating photovoltaic module manufacturers
After enough emergency orders, you develop a checklist. Not the checklist a manufacturer wants you to use—the one that ends with “please buy our product.” My checklist is simple, and it applies to First Solar or anyone else.
1. Manufacturing footprint and logistics. Where is the module made? For U.S. utility projects, that answer has legal consequences. The domestic content bonus under the IRA can change project economics more than the panel price. I’m not a tax attorney, so I can’t interpret every clause. But if a manufacturer can’t tell me the country of origin for the exact SKU they’re quoting, that’s a red flag.
2. Lead time versus the project schedule. A quoted lead time of “12–16 weeks” usually means 16. A quoted date of “arrives by May 30” is a promise, not a dream. First Solar’s domestic manufacturing footprint has made this easier for us, because we can allocate U.S.-built inventory without guessing about ship arrival dates.
3. Technology and real-world energy yield. First Solar panels are thin-film cadmium telluride, not crystalline silicon. People hear “thin film” and flash back to the old amorphous silicon days. That’s outdated. The company’s public Series 7 FT1 datasheet (2024) lists a module efficiency of up to 22.3% and a temperature coefficient of -0.29%/°C. The efficiency is lower than the best TOPCon modules, but the temperature coefficient is excellent. In hot climates, that difference narrows—and sometimes reverses—when you model energy yield instead of nameplate efficiency.
4. Warranty and bankability. A module warranty only matters if the manufacturer exists to honor it. When a project costs hundreds of millions, lenders’ engineers want to see long-term degradation assumptions backed by production data. First Solar’s 25-year linear warranty has always struck me as one of the more straightforward ones in any photovoltaic module catalog.
The honest limitation: who should not buy First Solar
Now the part where most manufacturer-focused articles get uncomfortable. Here’s my honest answer: First Solar is not the right answer for every project, and pretending otherwise would be stupid.
If you’re doing a residential rooftop with significant shading, you probably want a high-efficiency monocrystalline module. If you’re a small distributor with a dozen different project types, the narrow First Solar lineup won’t give you the catalog variety you need. If your project is outside the U.S. and your supply chain is built around lower-cost modules from other supply chains, you can find cheaper options. I’ve recommended alternatives in all these cases.
Look, I’m not saying First Solar is perfect. I’m saying that “not right for every project” is not the same as “bad.” It’s actually a filter: when a manufacturer is honest about where it doesn’t fit, I trust their “here’s what we’re good at” statements more. That’s a strange lesson, but it’s true.
Rebuttal: “But efficiency is still king”
“First Solar’s modules are bigger, heavier, and less efficient than a 600W crystalline module. How can you ignore that?”
I don’t ignore it. I just don’t put it first. If you’re building a utility-scale plant in the desert, you care about lifetime energy cost, not nameplate efficiency. Heavier modules add racking cost. But a lower temperature coefficient and a slower degradation rate can offset that. Run a model with your site’s actual climate, not a comparison table from a catalog.
Honestly, I’m not sure why the industry still treats nameplate efficiency as the headline metric. My best guess is that it’s the easiest number to put in a spec sheet. The assumption is that higher efficiency means more energy per acre. The reality is that real-world energy yield depends on irradiance, temperature, module orientation, and inverter design. Efficiency is an input to that calculation, not the answer.
Final opinion
So how should you evaluate photovoltaic module manufacturers? Start with delivery risk. Then look at technology and real-world performance. Then look at warranty, bankability, and the manufacturer’s financial stamina. Only after those steps does price become a meaningful comparison. When you run that process, First Solar panels will often make the shortlist for utility-scale U.S. projects—because they show up.
A solar panel that shows up on time is worth more than one that only exists on a spec sheet.
That’s my opinion, and it’s based on project schedules, not marketing brochures. If your project is different, you might make a different call. Just make it for the right reason—not because a catalog page looked better.