With its acquisition by Tesla confirmed yesterday, SolarCity has today shown us just what its tech can be capable of. The solar power firm has provided details of a solar panel and battery storage microgrid it rolled out on Ta'u in American Samoa, which is powering the island almost entirely.
SolarCity describes the deployment as "one of the world's most advanced microgrids." It features a 5,328 solar panel array that covers 3.5 ac (1.4 ha) and has an output of 1.4 MW. The array is coupled to 60 Tesla Powerpacks that provide 6 MWh of battery storage. These can be fully recharged by seven hours of sunlight and can keep the island powered for three full days without sun.
Prior to the microgrid, Ta'u had been using diesel generators for power, the diesel for which has to shipped to the island. Not only were both aspects of this environmentally-unfriendly, but it meant that the island was at the mercy of shipping deliveries.
"I recall a time they weren't able to get the boat out here for two months," island resident and shop owner Keith Ahsoon is quoted as saying in a blog post. "We rely on that boat for everything, including importing diesel for the generators for all of our electricity. Once diesel gets low, we try to save it by using it only for mornings and afternoons. Water systems here also use pumps, everyone in the village uses and depends on that."
Not only has the microgrid improved the energy security of Ta'u, it is also expected to save in the region of 109,500 gal (498,000 l) of diesel a year. This makes energy more affordable for the 600 residents of the island, as well as making energy generation cleaner and safer.
The project, which was funded by the American Samoa Economic Development Authority, the Environmental Protection Agency, and the Department of Interior, took one year to implement. It began in November last year was completed earlier this month.
The video below provides an overview of the project.