Clearly your site doesn't power itself by solar at night so I'm guessing a not inconsequential amount of batteries for power at night. I don't know what the power requirements of the site are but a 1000 watt electrical heater in a small space insulated could supply some very much needed heat. Most sites like this have a fallback power transmitting position if they need to reduce their power output because the battery reserve falls too low. I would think that would be acceptable to the company if you needed to "borrow" some juice for your heater to keep from losing some digits or dying.
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