@James Wilson yeah you're right that supercaps generally outperform lithium in the cold, but the capacitance drop is real and worth planning around — most EDLC supercaps will lose somewhere in the 10-20% capacitance range at -15°C compared to room temp, and ESR climbs at the same time, which means your effective runtime shrinks from both ends simultaneously.
The 24-hour runtime spec on the Power Kit is rated under normal conditions, so for a -15°C worst case I'd honestly budget for maybe 18-20 hours on a full stack and see how it performs in practice before committing to a deployment schedule. The good news is the 5-minute recharge characteristic stays pretty stable in the cold compared to what you'd deal with trying to charge a LiPo at sub-zero — that part of the supercap advantage holds up well.
For a farm equipment mount specifically, if you can get any thermal mass around the unit or even just orient it to catch some solar warming during the day, that'll help more than any firmware tuning will. Definitely worth reaching out directly through the Club if you want Moamen to weigh in on specifics — he's done field testing in some harsh conditions and may have more concrete numbers on the actual cells used in the kit.
