I mentioned yesterday that Sun Surveyor said I should have sun 9a-5p at this site. To be fair, my check was cursory – a quick sweep across the sky to get the general idea. Even that turned out to be quite accurate.
But first, breakfast.
I got up at 7am. The sky was starting to light up and it was 45F inside the van. I’m guessing it was 35-36F outside.
Because it was chilly I opted to cook inside. At City Market (the pot pie supplier) I spotted a 1lb chub of something in the Manager’s Special fridge display. I was hoping for ground turkey or beef for meatloaf purposes.
Turns out it was Impossible Sausage, a soy/yeast/something vegetarian product. I’m not vegetarian but I am curious about things. The chub was $3.25, marked down 50% from $6.50 (!).
It looked a little weird in the pan but smelled vaguely sausage-like. I cooked it down as one might do pork sausage. After cooking it looked a bit more like regular sausage. I heated up some flour tortillas and made cheese and sausage breakfast burritos. If I gave you one you’d probably ID as a low-quality sausage burrito like you might find at a gas station.
Would I pay $3.25 for this product? Probably. Would I pay $6.50? No, but I can’t imagine paying that for a 1lb chub of beef, pork, or anything else. I assume the high cost is a function of scale and not of the process or ingredients.
By 9am dappled sun was starting to hit the van and the battery bank stabilized (even or slightly net-positive rather than draining). I forgot about it but by 9:30a most of the shade was gone and the panels were pulling 325w. A few minutes later at 9:33a the shade was gone and output jumped up to 408w. After handling background loads in the van it was putting ~21A into the bank.
FLA banks have fairly high internal resistance so voltage will rise much faster compared to Li or AGM; by 9:40a the system hit Vabs and solar yield started dropping accordingly. This fast voltage rise isn’t good or bad; it just is. The upside for PWM users is the system will be able to make more power earlier. The chief downside is that it will require longer Absorption duration, and most controllers have insufficient duration under the best of conditions. Bulk and Absorption durations are interchangeable to some degree so FLA’s quick Bulk requires long Absorption. I account for this by
- maxxing the Absorption duration on my controller (180mins)
- Floating at the higher end recommended by the battery mfg
- setting Vfloat to Vabs when needed
The flipside of rapid voltage when under charging is rapid voltage drop when discharging. The capacity of a FLA vs AGM will be the same but the observed voltage of FLA under load will be lower. This can trick newcomers into thinking the FLA’s state of charge is lower than it actually is. It’s a non-issue unless voltage sags low enough to trip the LVD of a device.
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