It feels like a drug deal. Dense packets of merchandise are stacked up on the table. There’s a guy in the back room wearing latex gloves in front of a machine, testing and packing new goods. Across the table from us, Mr. Fujimoto and Ms. Wu are watching us expectantly. Mr. Fujimoto is leading the charge. He’s about fifty, with a shock of whitening hair and an earnest face. He speaks English in measured syllables, his tone is even and his eyes expressive as he speaks.
The room is small, with scuffed walls, torn carpet, with many of the styrofoam tiles missing from the ceiling, exposing the wires and pipes above. The center of the room is dominated by a large card table stacked high with taped cardboard packets, plastic chairs crammed in along the walls. In the back room, the man’s gloved hands never stop moving. The rest of the office is empty, the back hallways dark. Outside, rain is pouring down on Shenzhen.
Mr Fujimoto holds out his hand, and Ms. Wu casually places a knife into it, blade facing away from Fujimoto. The movement is silent, rehearsed. They’ve done this countless times. Fujimoto slides the blade under the tape of one of the cardboard packets, slicing the cover free. He places the knife to the side, reaches into the packet and draws out a silicon wafer.
I’ve never seen solar cells packed for distribution before. The first thing that strikes me is how incredibly dense the stuff is. A box containing 400W of silicon is about the size of a box of hot pockets. The table is stacked with boxes. Leaning back in his chair, Fujimoto describes a hidden world in solar.
These solar cells all come from semiconductor foundries in Taiwan. The foundries make silicon crystals, slice them into wafers, dope them with semiconductors and print conductive traces onto the wafers. The production process is pretty good, and 99% of the cells come out perfect. These are called grade A cells, and they go straight to the automated solar production lines that crank out the modules for rooftops and solar power plants. These cells go for $.65/watt. But one percent of the cells have a small flaw. Perhaps there’s a chip, or an uneven coloration, or a burn mark from the processing. These are called grade B cells, and they can’t go into the automated production lines. They’re not total scrap–they still produce 4W of power per cell, but there’s enough variation between cells that they wouldn’t be perfectly matched. They’re functional, but they can’t be sold through traditional channels, and this is where people like Mr. Fujimoto come in.
Fujimoto runs a clearinghouse for grade B cells. The world produces 30GW of solar a year, and the ~1% defect rate means that 300MW of solar cells get sold through clearinghouses to people who don’t care about the cosmetic defects. That small defect knocks 50% off the price of the panel, dropping it down to an incredible $.32/W. That’s not quite the cheapest solar in the world–the really beat-up stuff, with big dings, goes for ~$.25/W. All of these numbers feel surreal compared to the Solyndra-tinted world of US solar, where companies strive to reach the holy grail of $1/W silicon cells. On the other end of the world, we couldn’t feel farther removed from American’s automation and venture-capital-laden solar ecosystem. Instead of a world dominated by a few domineering (and hard-falling) giants, Asian solar production feels like a thriving ecosystem, full of companies of different shapes and sizes squeezing out a living for themselves anywhere they can fit. A rejected cell is a boon, a resource. Like a carcass in the African savanna–no part of the animal goes to waste. The dinged up solar gets cut up, the bad bits sliced out, and the good pieces turned into picosolar modules. Life finds a way.
Mr Fujimoto assures us that he has 200KW of solar in the office at all times, ready to ship out at a moment’s notice. I get that drug-deal feeling, again. If the need is urgent, Fujimoto says, he will hand-deliver whatever quantity of solar is needed within twenty-four hours. We ask him about international shipping and customs. Ms. Wu titters quietly behind her hand. 10KW of solar, Mr. Fujimoto says, is very small. He can fit 10KW of solar cells into my backpack. His customers run picosolar factories all around the world, and they fly in with a duffel bag, check the merchandise on the spot, pay in cash, and walk out an hour later with all the solar they need for the next six months. It shouldn’t be so surprising to us–like everything else we’re finding in the world of picosolar production, it’s shady, ad-hoc, and there’s a thriving industry flying well below the radar.
We ask about quality, and Fujimoto says it’s time for a demo. He grabs a shrink-wrapped package of solar cells and we head to the backroom, where a man is testing wafer after wafer on a semi-automatic wafer testing machine. Fujimoto whispers a few words in Mandarin, and the man pops open the package and slides a wafer into the tester. There’s a flash, and the I-V curve of that wafer pops up on a screen. Rows and rows of statistics follow, showing the power output, voltage, current, input flux levels, grid resistance and a million other factors I never even thought existed. They guarantee all their cells, Fujimoto explains, to a minimum output of 4W. Meanwhile, the worker keeps loading more and more cells into the tester. Test, FLASH, test. Fujimoto points out that the cell is producing at least 4W. Test, FLASH, test. He does it again. After ten cells or so, we say we’ve seen enough. Fujimoto keeps the man testing cells for another couple minutes, until he’s sure the point of the demonstration has sunk in. It has. Picosolar is an under-the-radar, ad-hoc world, but Fujimoto is no crook. His product might be someone else’s waste, but businesses run on these waste cells, and he’s serious about providing the best rejected cells he can. It’s not a scam and it’s not glamorous–it’s just business. It’s the business of pico solar, and it all takes place out of the light of day.