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I'd say home storage is about $750 a kWh in the UK. Plus installation. What do you think, is the future a domestic 50kwh battery in every house or will they be

I'd say home storage is about $750 a kWh in the UK. Plus installation. What do you think, is the future a domestic 50kwh battery in every house or will they be fewer giant ones owned and run by the power company out of sight?

ksec 6y ago
I still think it is far better to have a sort of semi centralise place for these Battery just for safety concern. Rather than having a massive battery in every flat. I would guess battery for house in rural area would work. But definitely not for cities.
marvin 6y ago
Well, Tesla currently sells a 50kWh battery that also happens to have a really nice car attached to it for $35000. That’s $700 per kWh. It stands to reason that home charging systems will soon come down in price, even if they don’t end up largely being eaten by BEVs with bidirectional charging ;)
- briffle 6y ago
  They sell a 13Kwh powerwall for $6500. That is down to $500 per kWh. Still not great.
Someone 6y ago
Third option: a mid size one in every neighborhood, charged by the neighborhood’s solar and wind (could be either owned by a power company or by the neighborhood) That gives some economies of scale, and keeps the amount of wiring lower.
pjc50 6y ago
I can't see a good case for the domestic batteries. Space is expensive. It exacerbates fire risks. It requires maintenance and replacement. Extra complications for renting. And the grid is already there. The smaller the "unit" of storage, the more you need. Doing it at grid level makes it easier to be incorporated into grid stability systems too, collecting payments for "fast frequency response". (Possible exceptions for crofters and islanders)
- mschuster91 6y ago
  The "good case" is for home owners with solar, as they can go down to 0% grid usage with adequately sized packs. As long as the price you get for feeding back to the grid is lower than the price of receiving from the grid, each kWh that got produced during the day using solar and consumed in the evening saves the homeowner money. Plus in the case of a grid failure the batteries can last quite a while if you restrict wasteful usage.
  - pjc50 6y ago
    The arbitrage on that has to be pretty thin? If the pack cost X and had to be replaced after Y years, can you recover that from each day's electricity? Personally I'm on the old feed in tarriff scheme which gives me a fixed price for generation, regardless of export or usage ...
    - bluGill 6y ago
      Depends solar with storage is one of the better deals for utility if the system is utility controlled: since you have storage they can decide when to take your power. The big problem with wind and solar alone is when it is on it is on with no care about who wants power. If they can take your power when people want it not when you generate it that is big for them. Of course the above requires a large amount of management. Right now it isn't worth their while to take your power that way. However this is an opening, an standard system so that the utility can automatically take power from little guys opens up a lot of opportunities that don't exists. Note that you should expect to pay about $10 a month for the above even if you are self sufficient. It should be worth that to you just to have the peace of mind that comes from utility backup when something fails. You can get that down, but probably at the expense of more equipment than you should reasonably buy and so your equipment costs are subsidizing someone else who doesn't spend as much on equipment.
      - pjc50 6y ago
        > pay about $10 a month for the above even if you are self sufficient This arbitrage is looking worse all the time? Given that power cuts happen only for an hour or so every few years, I'm happy to buy a couple of LED torches and deal with it. There seems to be an ideological bias to getting off the grid for no good reason? While remaining on the water, sewage and gas grids.
rootusrootus 6y ago
I think it will have to get much cheaper. Powerwalls are pretty awesome, but still quite a lot more expensive than a good quality lead acid setup, and if lead acid home battery systems haven't become popular yet, it's probably due to price.
madaxe_again 6y ago
If you’re doing lithium. With lead acid, you can get much, much better bang for your buck - as low as €85/kWh, no problem - and big OPzS cells will last for decades. I just put in 42kwh of storage last autumn for €6500. More like €155/kWh with vent caps, interconnects, longer life rather than the cheapest cells, etc. If you’re purely doing grid storage, a 5kva inverter/charger would set you back €1800 or so - and that’s basically it.
- snovv_crash 6y ago
  If you want the same cycle life as LFP cells you can only discharge to 50% though. Pb based cells are advertised in an extremely misleading manner IMO.
  - madaxe_again 6y ago
    Eh? Lithium will last 5-10 years doing full cycles. Lead will last 15-25 doing 80% DoD.
    - snovv_crash 6y ago
      Lead only gets the cycle count it advertises if you don't go below 50% on discharge.
      - madaxe_again 6y ago
        That really depends on the cell type. With OPzS they’re rated to 80% DoD, with C100 as the standard capacity rating used. You’re right that plenty of traction and gel cells get pretty tired pretty quickly with moderately deep cycles - I’ve just educated a friend on exactly this, as he killed two 12v batteries inside of six months by undersizing his storage and drawing too deep - 70% DoD daily on AGM batteries is murder. In our application, we rarely go below 20% DoD - but we could take them much, much deeper without unexpected implications for their life. The other nice thing about OPzS is they they’re each a single 2V cell. Means you can monitor for and track down individual duff cells, rather than having a whole battery fail. After 9 months, ours are still perfectly balanced, gravities all identical when charged to when they were new, literally zero problems.
_ph_ 6y ago
I think there is a place of both - and that is the beauty of a free market. In general, larger batteries run by the power company should be more efficient. However there are a few reasons why you also want your own home battery. - you become less vulnerable to short power outages - the power companies can't ask much more for electricity than solar plus battery would cost you - the grid might become more stable, as the battery can smoothe of sudden power demands, also grid fluctuations shouldn't affect you any more - on the one side, you probably can shave off a few dollars of your energy costs by not storing surplus solar vs. sending it to the grid - on the other side, home battery companies can't sell at prices higher than what the grid offers So I think there will be a combination for both, working together to get the costs down and supply more reliable. The number and the size of batteries installed at home in a region depends on the parameters of that region.

ksec 6y ago

I still think it is far better to have a sort of semi centralise place for these Battery just for safety concern. Rather than having a massive battery in every flat. I would guess battery for house in rural area would work. But definitely not for cities.

marvin 6y ago

Well, Tesla currently sells a 50kWh battery that also happens to have a really nice car attached to it for $35000. That’s $700 per kWh. It stands to reason that home charging systems will soon come down in price, even if they don’t end up largely being eaten by BEVs with bidirectional charging ;)

briffle 6y ago
They sell a 13Kwh powerwall for $6500. That is down to $500 per kWh. Still not great.

Someone 6y ago

Third option: a mid size one in every neighborhood, charged by the neighborhood’s solar and wind (could be either owned by a power company or by the neighborhood) That gives some economies of scale, and keeps the amount of wiring lower.

pjc50 6y ago

I can't see a good case for the domestic batteries. Space is expensive. It exacerbates fire risks. It requires maintenance and replacement. Extra complications for renting. And the grid is already there. The smaller the "unit" of storage, the more you need. Doing it at grid level makes it easier to be incorporated into grid stability systems too, collecting payments for "fast frequency response". (Possible exceptions for crofters and islanders)

mschuster91 6y ago
The "good case" is for home owners with solar, as they can go down to 0% grid usage with adequately sized packs. As long as the price you get for feeding back to the grid is lower than the price of receiving from the grid, each kWh that got produced during the day using solar and consumed in the evening saves the homeowner money. Plus in the case of a grid failure the batteries can last quite a while if you restrict wasteful usage.
- pjc50 6y ago
  The arbitrage on that has to be pretty thin? If the pack cost X and had to be replaced after Y years, can you recover that from each day's electricity? Personally I'm on the old feed in tarriff scheme which gives me a fixed price for generation, regardless of export or usage ...
  - bluGill 6y ago
    Depends solar with storage is one of the better deals for utility if the system is utility controlled: since you have storage they can decide when to take your power. The big problem with wind and solar alone is when it is on it is on with no care about who wants power. If they can take your power when people want it not when you generate it that is big for them. Of course the above requires a large amount of management. Right now it isn't worth their while to take your power that way. However this is an opening, an standard system so that the utility can automatically take power from little guys opens up a lot of opportunities that don't exists. Note that you should expect to pay about $10 a month for the above even if you are self sufficient. It should be worth that to you just to have the peace of mind that comes from utility backup when something fails. You can get that down, but probably at the expense of more equipment than you should reasonably buy and so your equipment costs are subsidizing someone else who doesn't spend as much on equipment.
    - pjc50 6y ago
      > pay about $10 a month for the above even if you are self sufficient This arbitrage is looking worse all the time? Given that power cuts happen only for an hour or so every few years, I'm happy to buy a couple of LED torches and deal with it. There seems to be an ideological bias to getting off the grid for no good reason? While remaining on the water, sewage and gas grids.

rootusrootus 6y ago

I think it will have to get much cheaper. Powerwalls are pretty awesome, but still quite a lot more expensive than a good quality lead acid setup, and if lead acid home battery systems haven't become popular yet, it's probably due to price.

madaxe_again 6y ago

If you’re doing lithium. With lead acid, you can get much, much better bang for your buck - as low as €85/kWh, no problem - and big OPzS cells will last for decades. I just put in 42kwh of storage last autumn for €6500. More like €155/kWh with vent caps, interconnects, longer life rather than the cheapest cells, etc. If you’re purely doing grid storage, a 5kva inverter/charger would set you back €1800 or so - and that’s basically it.

snovv_crash 6y ago
If you want the same cycle life as LFP cells you can only discharge to 50% though. Pb based cells are advertised in an extremely misleading manner IMO.
- madaxe_again 6y ago
  Eh? Lithium will last 5-10 years doing full cycles. Lead will last 15-25 doing 80% DoD.
  - snovv_crash 6y ago
    Lead only gets the cycle count it advertises if you don't go below 50% on discharge.
    - madaxe_again 6y ago
      That really depends on the cell type. With OPzS they’re rated to 80% DoD, with C100 as the standard capacity rating used. You’re right that plenty of traction and gel cells get pretty tired pretty quickly with moderately deep cycles - I’ve just educated a friend on exactly this, as he killed two 12v batteries inside of six months by undersizing his storage and drawing too deep - 70% DoD daily on AGM batteries is murder. In our application, we rarely go below 20% DoD - but we could take them much, much deeper without unexpected implications for their life. The other nice thing about OPzS is they they’re each a single 2V cell. Means you can monitor for and track down individual duff cells, rather than having a whole battery fail. After 9 months, ours are still perfectly balanced, gravities all identical when charged to when they were new, literally zero problems.

_ph_ 6y ago

I think there is a place of both - and that is the beauty of a free market. In general, larger batteries run by the power company should be more efficient. However there are a few reasons why you also want your own home battery. - you become less vulnerable to short power outages - the power companies can't ask much more for electricity than solar plus battery would cost you - the grid might become more stable, as the battery can smoothe of sudden power demands, also grid fluctuations shouldn't affect you any more - on the one side, you probably can shave off a few dollars of your energy costs by not storing surplus solar vs. sending it to the grid - on the other side, home battery companies can't sell at prices higher than what the grid offers So I think there will be a combination for both, working together to get the costs down and supply more reliable. The number and the size of batteries installed at home in a region depends on the parameters of that region.