In high lattitudes, during the winter months, days are short, and the sun doesn't appear far above the horizon. To make things worse, there's often a lot of cloud cover.
But winter is exactly the season when outdoor lighting is most useful..............
Now, you can banish those long winter nights
with the BorgCo seasonally-aware solar light.
It looks just like any other solar light, except it sits on a large, very heavy insulated box containing four high-capacity rechargeable batteries, Lead-acid or NiFe (It needs to have a very low self-discharge rate). Incorporated into the system is a low power microcontroller and a GPS system.
Once every 24 hours or so, the microcontroller powers up the GPS and checks its location and corrects its internal clock.
When it goes dark, the lamp activates. At a preset time, maybe midnight, the lamp is switched off.
During the day, the photovolatic harvests whatever energy it can; but the bulk of the stored energy comes from those long, bright summer days.