Solar deck lights with other uses

[papaof2]

tools.woot.com/offers/16-pack-solar-waterproof-led-deck-lights-4?ref=w_cnt_cdet_tool_dly_wobtn $19.99 + tax + ship

16 solar-charged deck lights - two screws hold them to the rail and the lights shine in/down on the deck. Probably useful anywhere you have a place to mount them - corner of wood building, swing frame, firewood rack, on fascia for downlights, top of fence to light inside the fence, limited only by your imagination. Use clear double-stick mounting tape (3M makes one wide enough) with the solar cell against the inside of a South- or West-facing window and have after sunset lighting daily without touching anything.

Until midnite tonight 2 June 2023.

[feralferret]

I just wish they would give a bit more detail in the specifications as to lumens, operating time, etc. Woot is rather bad in that department on most of their listings.

[papaof2]

True. Most of the "packaged" solar devices seem to come with near-zero information. As they make the lights smaller, they're moving to AAA NiMH cells which are too small to have much AH capacity. Previous generations of solar walkway lights and the like used AA cells and the 300maH or 600maH cells could be replaced with 1500 or 2000maH cells and have lights that worked all night most of the year.

Now most of my outside solar lighting (other than the walkway lights) have some flavor of rechargeable lithium cell in them so I'm not replacing dead NiCad or NiMH cells in a couple of years.

Speaking of replacing batteries, the 420AH AGM bank for the backup power system is more than 4 years old and when I disassembled the bank to test the AH capacity of each battery yesterday (yearly maintenance task), I was disappointed to find that the rated 420AH of batteries now has a total capacity of 138.9AH. Typical AGM life is 3-5 years, so I'm not surprised, just unhappy that it's already happening :-( The battery shop 30-odd miles from me does have good prices on large (230AH and up) LiFePO4 cells, with an additional discount when you buy 16 or more cells. The EVE 230AH Grade A cells are $120 each in less than 16 so 16 * $120 = $1920 plus state and local tax or just a bit over $2000. 16 cells would make four "12 volt" batteries with a total capacity of 4 * 230 = 920AH. Still needs a BMS per battery and some circuit breakers but I have almost everything except the batteries and some hardware (BMS, fuses, circuit breakers). That would power fridge, some LED lighting, freezer on 2 hours every 8 hours, 5000 BTU window A/C running at full cooling 8 hours/day for 30 hours with no solar or generator input. That would get us through one full 24 hour day. If we have sun, 600 watts of solar panels would take that out to just over 2 days or 1100 watts of solar would take it out to 6.5 days. Or I could run the inverter generator to recharge the battery bank. I could sharecropper 1100 watts of solar panels on the roof of the equipment shed out back in a matter of hours and run some small plastic irrigation pipe to have waterproof "conduit" for the wiring from the solar panels to the house. As the longest power outage we've had here was 16 hours, the LiFePO4 battery bank would provide a long "cushion" for the next outage. Just need to see where some $$$ can be moved from other things to "household maintenance" :-) Since I have an adequate vehicle, it's cheaper to drive the ~70 mile roundtrip than to pay truck shipping for UN3480-class cargo (lithium-based batteries).

I'm s-l-o-w-l-y recovering from the spinal fusion last September and I could probably do the solar work with a little help. I did get the 420AH battery bank apart yesterday, get each battery tested and get it back together today - given that the battery bank is on one of the lower shelves of a heavy duty shelving unit and it requires working with your body in odd positions to open and restore connections, that's a large degree of progress. Our somewhat younger neighbors to the West have always been helpful (sometimes moving downed limbs to their area of "woods" before I get out to move those limbs) - but they're out early every morning to walk their dog and that's much earlier than I need to be up ;-)

I need to do some $$ math...

[feralferret]

"Since I have an adequate vehicle, it's cheaper to drive the ~70 mile roundtrip than to pay truck shipping for UN3480-class cargo (lithium-based batteries)."

You got that right! The regulations and surcharges for shipping lithium batteries are a pain.

Glad your back is continuing to progress.

[papaof2]

The little truck does 18MPG in town and 20-22 on the highway. ~70 miles is 3.5 to 4 gallons at $3.299/gallon or $11.55 to $13.20. Shipping of one 2lb battery from PA was $12. 9lb/cell is almost 150lb for 16 cells so driving is probably a LOT cheaper ;-)