No idea, but I´ve just come back from staying with a family on an island in the San Blas, home of the Kuna Yala,(Did I mention you could walk round it in 3 minutes, it had a white sandy beach and we had the crystal clear water to ourselves?) and I was pleased to see that this was the most modern device on the entire Island.
A six foot solar panel...
Leading to a hefty battery...
That powered this one inch light bulb...