28 Jul Arctan Array
The array for the Stanford Solar Car Project’s 2015 World Solar Challenge Vehicle, Arctan, incorporates some of the most advanced photovoltaic and encapsulation technologies. The primary component is SunPower Maxeon® cells. These back contact cells increase functional area and avoid shading due to the metal paste from front contact soldering. Once the cells were aligned and soldered at our lab, we were lucky enough to travel to SunPower’s R&D lab to encapsulate our modules. The encapsulation stack was similar to that of the 2013 vehicle, Luminos, but used slightly different materials. With guidance from Robbie Coopernurse and Kat Han (founder of the Oregon State Solar Car Team) of SunPower, we used a vacuum lamination technique to bond the layers, instead of the vacuum bag compression in our standard industrial oven used for Luminos. The new array achieved a 50% weight reduction over the Luminos array, and features a smooth, ultra-dark appearance. We are yielding similar efficiency to Luminos, but the flat contour of Arctan and the off-center bubble should provide a noticeable increase in power over the course of a day.
We used a marine gap filler to fill the voids between modules, and are now very happy with the seamlessness of our car’s top surface. Additionally, the new array is significantly easier to clean and is fingerprint resistant.
The generosity of SunPower’s R&D team is a donation that was invaluable to our ability to produce such a high quality array for Arctan. We cannot thank them enough for the time they spent with us and the knowledge they imparted. We are all extremely proud to be using their cells on our 2015 car!
-Alex Lubkin and Matthew Matera