I've been spending more time thinking about the cabin's energy use: how to reduce it and how to supply it. The new solar panels are working great, despite not really having a sunny day since I put them up. And the second battery means I have enough energy stored, if the sun doesn't shine for a day or few.
Lighting is one of my major power needs, and so I've installed two 12 volt lighting fixtures wired directly to the battery. Going directly to the battery means no inverter is needed just for light, which is more efficient.
Initially I purchased a pair of Chichin 3 watt bulbs (three!?!). As you can see in the photo, these drew a paltry 250 milliamps. I've got a pair of batteries totaling about 210 amh, so if the bulbs worked they would have run until about spring.
However.
The Chichin bulbs turned out to be a big waste of time, as they began flickering within two weeks. Despite their efficiency, not a good buy.
I'm now using a pair of 7 watt Sunthin bulbs. These are much brighter and still only draw 450 milliamps. They definitely appear more than twice as bright as the 3w bulbs, only need 80% more energy, and have continued.
The Sunthin bulbs have a soft, warm color to them so it doesn't feel like you're hanging out in the emergency room or a police interrogation cell. Would recommend.