wattmatters
Solar Wizard
Just for clarity, what's your definition of shallow discharge?if the 4 tenets mentioned in the first post are followed.
Just for clarity, what's your definition of shallow discharge?if the 4 tenets mentioned in the first post are followed.
I wouldn’t beYou'd be amazed at how much more life you can get out of even consumer-level lead-acid if the 4 tenets mentioned in the first post are followed.
If the power stays on and my generator works correctly the batteries will be on discharge less than 2 hours per year. So very shallow depth of discharge.Just for clarity, what's your definition of shallow discharge?
Fun fact:... and I live in a country with a life expectancy of around 83. But then, it was obviously about quality of life ;·)
Actually, I semi-panicked more at 29. By 49, I had got used to the idea. At 59, 'What, still around? Can't be too bad'. At 69... haven't got there yet. And I don't think it's very likely I will (well, hopefully :·)
OK, that's not a lot! Such a cool pic.If the power stays on and my generator works correctly the batteries will be on discharge less than 2 hours per year. So very shallow depth of discharge.
I hadn't really noticed. All my cars have had them in the engine bay, including the latest one. Keeps the high current cable to the starter motor short.I think temperature controll is a big factor. Have you noticed than many new cars have the battery in the trunk, out of the hot engine compartment.
Long (long) ago when I was an apprentice we visited one of the last Strouger exchanges in the UK (Bath IIRC).It's a telephone office DC power plant.
It's why your phone and data still work when the power goes out.
Try to keep the temps below below 80f if possible. Heat kills lead acid batteries.OK, that's not a lot! Such a cool pic.
I hadn't really noticed. All my cars have had them in the engine bay, including the latest one. Keeps the high current cable to the starter motor short.
My own battery bank will be subject to environmental temperature fluctuation. They are inside a timber housing which is under the wide eave of my home. We are a mild to warm climate. I kept an eye on temps in the housing this Winter and lowest in the housing would be ~15°C. Not sure what Summer temps will reach in there (it can get hot here) but I'm not looking to get 30 years out of them!
Discharge won't be a lot but definitely more than your telco centre batteries. A typical grid outage will draw about 10% of (nominal) capacity and we average 10-12 of those/year. Occasionally we'll get a longer outage so 50% of capacity ~= 15 hours, not including supplemental energy from solar PV. I can plug a generator in to boost charge if we have a particularly long outage (we've had a 2 day outage before).
Charging / float energy is normally supplied by solar PV on a typical daily cycle and there is a small constant load so they will draw perhaps 1% of capacity each night before solar PV tops up/floats them the next day. It's also programmed to supplement charging from the grid if required and the parameters for triggering grid charging vary depending on time of day (lower state of charge trigger early in the morning, higher state of charge trigger at end of day and variable trigger in between). The other thing they do is provide some electrical ballast as I have a pool pump which is supplied energy from the off-grid solar PV.
It's all an experiment really. I wasn't looking for a deeper daily cycling, just backup and ballast and the Powersys units seemed pretty capable and were not particularly expensive. Way cheaper than a 48V lithium option.
What I'm hoping for is that they received similar treatment to yours. The typical city based data/telco centres here would have pretty reliable grid supply, and would also have generators to manage the bulk of backup energy needs, so the batteries would be a fill in. I'm guessing they have a routine replacement period for their batteries. I load tested the first bank and it performed really well. Not load tested the second bank yet but they came from same supplier/batch.
Thanks. I'll keep an eye on it.Try to keep the temps below below 80f if possible. Heat kills lead acid batteries.
How can lead last that long? I have always been told they will only last about 5 years!
thanks! that was like a throwbackI thought some of you might find this interesting.
Here are a few pictures from work.
Just for clarity, what's your definition of shallow discharge?
Disharging anything less than about 5 percent of rated capacity is considered "short cycling". (if you are actually cycling, and not standby)
What short-cycling does is not allow for an overall smooth layer of sulfate to form nicely over the plate surfaces. The natural process of sulfation during discharge that is - not neglectful sulfation.
Instead, without a deep enough discharge of at least 5%, tracks and channels can form instead of a smooth surface during initial discharge and cause issues with parts of a plate and it's active material doing all the work initially in a repetetive shallow discharge environment.
So it's application dependent. The extreme would be purchasing a 100ah pure-lead agm and use it for charging your cell-phone and charging the agm back up again every time. (silly extreme).
There must be another piece of equipment in the field that isn't backed-up. The DSL signal has a limited range so there is probably a piece of equipment in your neighborhood that has also lost power.Must not be what the phone company backs DSL with, if the power goes out my DSL goes out about 5 minutes later.
I work from home and put my whole house through an inverter with PV and a battery, and was disappointed to find out the phone company only has about 5 minutes of power backup on their end.