In article ,
wrote:
The OP said solar powered ideally, which means mains is available. You
could supplement the solar - or replace it if running on PIR only - with
a small mains 12-15v PSU sending charge current down a long thin wire.

Under the worse conditions - mid winter - the batteries will be on charge
for a shorter period than the lights are running. So not quite sure how
you work out the power supply cable can be smaller than the light one?
Unless of course it is at 240v.

--
*If I agreed with you, we'd both be wrong.

Dave Plowman London SW
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