On 14/06/2015 09:13, Brian-Gaff wrote:
One assumes full sun at the equator might be more powerful than full sun
at 4 in the afternoon in the winter in the uk.

Not much. a bit, because it's going through more air. The big thing on
an installation is that it won't be pointed at the sun, which presumably
a mobile phone charger will be.

The catch is of course it won't often be sunny in the winter in the UK!

Andy