(Updated) While a 50MW PV module line may seem like a drop in the capacity bucket of a firm with some 2GW of production capability, the importance of Suntech’s Goodyear, AZ, goes beyond the modest percentage of the enterprise-wide nameplate it represents. In addition to being the company’s first major facility outside of China, the site will be a prime example of the concept of distributed manufacturing—the idea of making panels close to where they will be deployed—when the US plant starts shipping its products 30 miles (~50km) west to the Mesquite Solar 1 project for installation in the initial 150MW of the utility-scale solar power farm. For the parent company, the Goodyear plant also will be a testbed of sorts, since it features a higher level of automation than the more manually oriented modcos operating back on the company’s Middle Kingdom campuses.
Housed in a 117,000 sq ft (10,869 sq m) building outside of Phoenix a few miles south of Interstate 10 on the edge of open desert, the Suntech factory officially opened in October. The company just added a third shift and increased the workforce to more than 100, which will increase the production line utilization and boost capacity to around 50MW.
There’s plenty of room for a second production line to be brought in, and that’s the plan. With some process optimization and a fully staffed 24/7 schedule, the factory will eventually reach the neighborhood of at least 120MW capacity in a few years, the company believes.
Solar parking canopies will eventually be installed as well, with the power system providing juice to the plant as well as shade to the vehicles. Onsite side-by-side test arrays of the company’s modules versus competitive units are also planned.
While the shopfloor contains a significant amount of automated gear, it’s not what one would call a “lights out factory.” The human element still has a important role to play, especially in the areas of quality inspection, rework, and loading/unloading. But key production steps often done by hand on a more labor-intensive line—such as stringing, soldering, framing, and microcrack inspection—rest in the robotic realm in the Arizona works.
The automation system is not without its learning curve, as I witnessed from the catwalk overlooking the production floor. At one point, the red light came on as several cells dropped from the robot arm’s grip in the stringing area, apparently because the tool may have run out of ribboning material. Production stopped for a few minutes, then resumed with the twinned pair of robots continuing their techno dance, relentlessly placing the 12-celled strings on the glass substrates.
The global supply chain feeding the factory’s bill of materials includes links from Florida (EVA from STR), China (tempered low-iron patterned glass, aluminum frames, Tonsan sealants, and Suntech’s own PV cells), Japan (specialized materials), Austria (Isovoltaic backsheets), and Switzerland (Meyer Burger group production equipment). Patrick Lasswell told me there was an ongoing effort to source more North American suppliers of glass, frames, and other materials.
The Suntech team works “very closely” with the equipment vendors from MB, “on a lot of different levels,” according to the industry vet. He sees some areas for improvement.
“I’ve been in this business a long time, and I’m not the least bit shy—I think there are things that they can seriously improve about the way they handle this kind of project,” the engineering manager said without going into the juicy details. “So I’m working with more senior people at 3S Modultec to improve their project management skills.” He wasn’t involved in the vendor selection process, joking that “I didn’t cook this soup, but I have to eat it.”
There are a few nonstandard aspects of Goodyear’s production line. Because of the very low humidity of the southwestern US climate, some materials won’t cure properly without additional treatment. For Suntech, after the framing step, the adhesive used to make the edge seal or “cushion” must go through a “humidity soak” on a tool specially built by a Suntech subsidiary.
“In Arizona, it’s so dry here, we can’t get the silicone to cure as fast as need it to, so we have a mechanical process for curing where it adds 50% humidity to the module at 25°C, and the module stays in the chambers for two hours to do a final cure,” explained my tour guide and communications manager, Krystal Book.
Once the soak is completed, the panels proceed to the final test area, where a robot flips them “sunnyside up” for a run through the Pasan solar simulator. After testing, they are then sorted by amperage into three groups, which helps customers reduce string mismatch errors and enhance their system outputs, according to Suntech.
The humidity curing tools are big, capable of holding and processing many stacks of incoming modules, with a steady inflow and outflow over the course of a workshift. But the added production step adds a bit of complexity to the line-balancing calculation, since one could envision potential bottlenecks, especially on the incoming side.
Another unusual facet of the Goodyear plant is the lack of cleaning systems for incoming glass. The materials are cleaned at the glass manufacturer’s house, and then placed in hermetically sealed packaging and shipped to the modco.
“This is the first time I’ve ever seen a plant that didn’t have a wash-up, but the glass is pretty clean,” said Lasswell, who has eyeballed and worked in many PV factories during his more than 30 years in the business. “There has been some dust on the glass a few times, and we have some small vacuum cleaners to clean that up.”
Equipment changes were also happening on the shop floor during my early April visit, with automated framing tools recently installed to replace the semiautomated gear, which had stood in on the line until the new, higher productivity tools (which had been delivered behind schedule by the OEM, according to Book) arrived to take their rightful place.
Several megawatts of stacked product were staged in the current warehouse area, the boxes stacked up, each with 21 of the 280W Vd series modules (almost 6KW per container) inside waiting for shipment. Incoming materials also took up their fair share of space, with tubs of silicone, boxes of cells, and pallets of packaged glass ready to enter the flow.
The factory’s 120MW-ish production capacity target isn’t etched in stone, according to Lasswell. The final number could actually be double that or more.
“We have in the budget enough for a doubling of the capacity of this line,” he explained. “I’m looking at that from a couple different points of view because we’re not really sure how big we want to make it. I’ve also been asked to look at squeezing as much capacity as I can out of the available space. There’s a whole section of the building that’s not occupied, and we have the first right of refusal . We are in discussion to take that part of the building, so we could push the warehouse down there, and put in more production lines.”
For now, the factory runs one product—the large, 2- x 1-meter 72-cell, 280MW Vd series commercial and utility-scale polycrystalline module—but the equipment is designed to handle different panel configuration and cell types. But Lasswell cautioned that “it runs about the same number of units per hour, no matter what kind of panel is running, so if you drop the size of the panel down to something more appropriate for the residential market, your cost per watt goes up.”
While there’s no sign that the company plans to vertically expand its manufacturing presence in the US, the Suntech brain trust “is very interested in our experience with this equipment,” he said, “but whether or not they would plan on replicating this line [for future moduling plants], I don’t know.”
One of those future plants could even be built within spitting distance of the Goodyear site’s Cotton Lane address, if North American market demand were to go ballistic in a few years. Lasswell said there are many suitable buildings in the area, noting in particular an old Rubbermaid factory, a large, empty building loaded with utility infrastructure. “It would hold a lot of module assembly lines,” he smiled.
(Update: The Goodyear plant is not strictly speaking Suntech's first manufacturing facility outside of China. Walker Frost, a communications manager for the company, reminded me in an email that it has a small module plant in Saku, Nagano prefecture, Japan. Although the factory, bought in the MSK deal and now called Suntech Nagano, has a nameplate capacity of 100MW, Frost told me that it only produces small-volume special orders these days, averaging <10MW of annualized run rate. He also said the facility was undamaged by the recent earthquake in Japan.)