Another very informative article by FastCompany, but this time detailing the struggles of getting the the Buffalo gigafactory online:
To reach the 100-megawatt goal, sources indicate that the pilot production line in Fremont would eventually need to yield between 800 to 1,000 high-efficiency Whitney panels per day. But the team was not able to automate the process consistently enough to produce more than dozens of Whitney panels per day, according to people familiar with the matter. Most of the production resulted in “scrap,” they say. “The big problem was simply that they couldn’t scale up the technology to the point where you could run it in a factory,” a source familiar with the development explains. A spokesperson for SolarCity acknowledges that the company ran into issues with some of its automation equipment, but says this was “not necessarily” due to its cell technology. Multiple sources also claim that even the Whitney panels that did make it through the automation process in Fremont were not reliable enough for the market. Normally, solar panels are designed to last several decades on rooftops, but according to these sources, in early 2016, the Whitney panels failed internal tests that determined whether they met industry-standard longevity. SolarCity decided to go ahead with installing trials on around 70 customer roofs. But in many cases, the Whitney panels lasted just weeks before malfunctioning, and later needed to be removed, according to two sources familiar with the matter.