9 ms·

I don't have any specific wear numbers, but a system like this is going to be designed for maximum lifespan not for limited cases where you want every possible

I don't have any specific wear numbers, but a system like this is going to be designed for maximum lifespan not for limited cases where you want every possible drop of energy that can be put into or out of the battery. I suspect that the cells are never charged above about 75-80% of capacity and probably are never discharged below 20-30% of capacity. Avoiding both extremes should greatly extend the number of available cycles from hundreds to thousands or more.

ksec 8y ago
But even 1000 cycles... assuming 0.5 cycles per day gives you ~6 years life span? Sounds a little too low.
- agumonkey 8y ago
  yeah indeed
- deleted 8y ago
  [deleted]
- Retric 8y ago
  The payback period is ~18 months so lasting less than 10 years is mostly irrelevant. On top of that these systems are still useful well below their original capacity, so they can rather than a sudden huge bill you simply add more capacity as the original battery’s degrade in a fairly predictable fashion. Over time you end up with a much smaller annual investment than your saving every year.
  - agumonkey 8y ago
    payback is not the goal though, it's about avoiding sucking earth resources
    - tankenmate 8y ago
      You can always recycle the batteries and use it to create new batteries.
      - adrianN 8y ago
        Recycling uses resources too.
        Retric 8y ago
        But grid batteries directly save resources, in this case money saved is a good proxy for less resources used.
    - dsfyu404ed 8y ago
      Payback is a prerequisite to people to actually buying your less earth sucking technology so while it might not be the end goal it's a goal nonetheless.
- manicdee 8y ago
  3000 cycles “lifespan” but most of the degradation happens in the first couple of years with the rate of degradation about 3% a year, capacity still remains and the product will still have significant capacity in 20 years. As opposed to say a synchronous converter which requires annual downtime and continual replacement of parts, and (being limited by inertia) can’t provide the same stability and support that a battery can.
Someone 8y ago
”but a system like this is going to be designed for maximum lifespan” I don’t know what this system was designed for, but a product that costs $66M and saves $40M in its first year need not be designed for a long lifespan. It seems scrapping this after 3 years still would net you a nice profit margin. So, depending on how much designing for a long lifespan costs, that may be a thing of the past.
- blattimwind 8y ago
  > It seems scrapping this after 3 years still would net you a nice profit margin. 110% eco.
  - Tharkun 8y ago
    AFAIK these things can be recycled with relative ease. I wonder at which point it would make sense to include a small battery recycling plant with large installations like this. "Cell XYZ is damaged, remove, replace and recycle"

ksec 8y ago

But even 1000 cycles... assuming 0.5 cycles per day gives you ~6 years life span? Sounds a little too low.

agumonkey 8y ago
yeah indeed
deleted 8y ago
[deleted]
Retric 8y ago
The payback period is ~18 months so lasting less than 10 years is mostly irrelevant. On top of that these systems are still useful well below their original capacity, so they can rather than a sudden huge bill you simply add more capacity as the original battery’s degrade in a fairly predictable fashion. Over time you end up with a much smaller annual investment than your saving every year.
- agumonkey 8y ago
  payback is not the goal though, it's about avoiding sucking earth resources
  - tankenmate 8y ago
    You can always recycle the batteries and use it to create new batteries.
    - adrianN 8y ago
      Recycling uses resources too.
      - Retric 8y ago
        But grid batteries directly save resources, in this case money saved is a good proxy for less resources used.
  - dsfyu404ed 8y ago
    Payback is a prerequisite to people to actually buying your less earth sucking technology so while it might not be the end goal it's a goal nonetheless.
manicdee 8y ago
3000 cycles “lifespan” but most of the degradation happens in the first couple of years with the rate of degradation about 3% a year, capacity still remains and the product will still have significant capacity in 20 years. As opposed to say a synchronous converter which requires annual downtime and continual replacement of parts, and (being limited by inertia) can’t provide the same stability and support that a battery can.

Someone 8y ago

”but a system like this is going to be designed for maximum lifespan” I don’t know what this system was designed for, but a product that costs $66M and saves $40M in its first year need not be designed for a long lifespan. It seems scrapping this after 3 years still would net you a nice profit margin. So, depending on how much designing for a long lifespan costs, that may be a thing of the past.

blattimwind 8y ago
> It seems scrapping this after 3 years still would net you a nice profit margin. 110% eco.
- Tharkun 8y ago
  AFAIK these things can be recycled with relative ease. I wonder at which point it would make sense to include a small battery recycling plant with large installations like this. "Cell XYZ is damaged, remove, replace and recycle"