8 ms·

This is something I've been curious/interested in for a long time, so its good to see that somewhere out there (random Pacific islands aside), there's communiti

This is something I've been curious/interested in for a long time, so its good to see that somewhere out there (random Pacific islands aside), there's communities making it work. Some rough numbers I did a month or two ago - Tesla offers a megapack that has 3.9 MWh at a cost of $2.4m. "In 2021, the average annual electricity consumption for a U.S. home was 10,632 kilowatt-hours (kWh). Or about 886 kWh per month." That's about 30 kWh per day; my community has 45 houses, so use of 1.35 MWh in total, so a megapack will provide power for 3 days for the community at a cost of ~50k per house. Probably not worth it and I'd expect 3 days to be overkill. But a community that was double our size will have a cost of about 25k per unit for 1.5 days of power - which doesn't sound too bad to me. Another thing I've found interesting is Anker seems to be getting into the home power business - https://www.anker.com/anker-solix/home-energy-solutions?ref=anker-solix-brand https://www.anker.com/anker-solix/home-energy-solutions?ref=... - which I'm hopeful about, since it doesn't seem like anyone except Tesla has been able to make something that feels simple/easy/attractive. Every time I've look at Powerwall alternatives I'm been unimpressed by the offerings; maybe Anker can deliver.

hkt 3y ago
It'd become much more sustainable to do what you're talking about if it was accompanied by energy saving measures. Do it well and you could easily aim for 5kWh per day per house by minimising heating and cooling choices.
momirlan 3y ago
anker, being a Chinese manufacturer, doesn't have much chance to penetrate the western markets. even assuming they can develop a dependable product. but I wouldn't trust more than a headphone, or a wall charger from them.
- vorpalhex 3y ago
  Anker knows batteries and their LiFePO4 batteries are solid stuff (as are their traditional lithium cells). Even if you prefer a US maker, competition will help lower prices.
- mschuster91 3y ago
  I agree on being careful with China goods in general, but Anker is one of the very few very trustworthy brands out there. IIRC, the only fuck-up regarding batteries they did was with the 535 power banks, and they handled that one very solidly [1]. [1] https://www.cnet.com/tech/computing/anker-recalls-some-535-power-banks-over-fire-risk/ https://www.cnet.com/tech/computing/anker-recalls-some-535-p...
  - mschild 3y ago
    Unfortunately, no they're not. Anker owns Eufy and they had some massive issues. https://www.digitaltrends.com/home/anker-admit-eufy-security-issues/ https://www.digitaltrends.com/home/anker-admit-eufy-security...
- croes 3y ago
  Pretty strange view, when you consider that China still is the workbench of the world.
  - momirlan 3y ago
    lol
s_tec 3y ago
I recently installed an Enphase home backup system as a DIY project (crazy, I know). The biggest problem with any home-backup system is moving the loads onto their own sub-panel. When the utility goes down, power needs to flow into the home, but not to the rest of the neighborhood. To do this, a switch needs to physically disconnect the utility meter from the main loads panel. If this isn't possible (such as when the meter is integrated into the panel), all the loads need to move to a sub-panel. This is the hard part. Once the meter and main panel are separate, the various backup solutions become pretty similar. The disconnect switch installs between the two, with the solar and battery attached. Sometimes the disconnect switch + solar + battery are all in one unit (like the Bluetti EP900), while sometimes the solar inverter, battery, and switch are all separate units (like Tesla or Enphase). The Tesla switch and battery are sleek & glossy, but the inverters are ugly. The Enphase stuff isn't quite as shiny, but at least the boxes look consistent. Performance-wise, the systems seem pretty similar as well. Most systems are around $10K for 10KWh of capacity, with somewhere around 6-9 KW of peak discharge rate. I imagine these prices will drop a lot over the next decades. If the battery becomes obsolete, just install a different system. Once the home is correctly wired, swapping the storage system should be pretty straightforward.
- rstupek 3y ago
  Why did you choose the Enphase system versus any of the others? How much capacity did you install and is it upgradeable?
  - s_tec 3y ago
    I like the distributed architecture. Each solar panel has its own inverter, as well as each battery. If I want more panels or batteries, I just add them in parallel with the existing panels or batteries. If a panel or battery goes down, the remaining ones keep working. Avoiding high-voltage DC also makes the project more DIY-friendly. The downside is that Enphase requires users to take online classes before they grant access to the installer app (easy but time-consuming). Right now I have 3.8KW of solar and a single 3.3KWh battery. We are producing more than we use most months, so the solar is good but the battery is undersized. If we have an extended grid-down scenario like what happened in Texas, the system will mainly provide daytime backup plus a few evening hours. This is still better than nothing, and we can easily add more batteries as we have the budget.
maliker 3y ago
Pair the storage with some solar, and you could probably reduce the storage size or increase the survival duration (or both). Here's a fun tool that lets you play around with the balance of these things and see the expected cost: https://reopt.nrel.gov/tool https://reopt.nrel.gov/tool
adql 3y ago
> Probably not worth it and I'd expect 3 days to be overkill. But a community that was double our size will have a cost of about 25k per unit for 1.5 days of power - which doesn't sound too bad to me. If you're not looking to go completely off-grid, I think you want to double it again. At basic level, battery pack is there to soak solar power during a day and give it off when the solar is down. 16 hours is enough to cover most or all of that.. I think the model could work if the local community basically "sold" the battery storage capacity to the users. Pay few cents for kWh to store it for 24 hours, anything in excess can be sold back to residents at slightly lower than market price, producing some money for maintenance and upgrades.
nuancebydefault 3y ago
I never stop to be amazed how average consumption figures in the US are often at least 100 per cent bigger than in Europe. At least for water and electricity, let alone fuel. Just a thought that naturally pops up... : If you take the reasoning one step back, wouldn't it be easier to optimize the consumption side (low hanging fruit) in favour if optimizing the cost per unit of energy? The latter seems a lot of effort, at least for the devs.
- cultofmetatron 3y ago
  its pretty easy to understand when you spend significant time in both. european cities: typically built for density. I'm never more than a 10 minuite walk to a grocery store. I can hop on a train or tram to get to work and I can usually stop to get groceries for the day on the way. if you're in a city like athens, you can get fresh fish and meat. was probably dreaming of finding a mate or eating fresh acorns on the other side of the pasture barely a day ago. USA: Its a hellish landscape of urban sprawl. want to get sone milk or eggs? its illegal in most place for there to exist a grocery store within walking distance. be prepared to walk along the side of a busy road to get to a convenience store which might have what you are looking for. maybe there's a sidewalk if you're lucky. Every damn trip requires a car. your work place is probably 30 min drive minimum. there is no other way to get to work. since getting to the store requires effort, you're going to go get a week's worth of groceries to save time. fresh meat? nah, killed weeks ago in a centralized slaughter house and shipped accross the country after a life of being fed corn farmed with chemical fertilizers and shipped to the animals in temperature controlled facilities. better keep a large fridge to hold it all. wouldn't want it to spoil before you eat it. you literally can't live in the USA without increasing your consumption. its built into the dna of our infrastructure.
  - zamfi 3y ago
    Neither Europe nor the USA are a monolith in this regard. Live in NYC or even S.F. and you can 100% walk to the store and take transit to work. Live in rural or suburban Germany and you’re driving everywhere.
oh_sigh 3y ago
Realistically you could get that number 6x smaller, because people could voluntarily cut their usage from 30kwh to 15 when the power is out, and 1.5 days of power is probably overkill when 12 hours would get you through 99% of power out scenarios in America. On top of that, when the grid is functioning normally, you could use the batteries to get cheaper electric rates with time of use pricing.
pests 3y ago
Surely doubling the households would only half the cost or the duration available, not both?
- HeyImAlex 3y ago
  I don’t think so? Household Cost = Total Cost / Households, Household Duration = Capacity / (Household Usage * Households), Houshold*2 would half both.
  - pests 3y ago
    Oh duh, right. Thanks.
mshenfield 3y ago
25k per unit, assuming the battery lasts 5 years, is uneconomically high at $5k/year per home. A 100kw generator can produce enough power for 100 homes, costs ~$50k all in, and ~$1k per day in fuel costs to run during an outage. Assuming the generator also lasts 5 years, that's only $100/year per home, 50x less than the battery solution. Batteries are for the foreseeable future way too expensive.
tzs 3y ago
You probably should divide all those number of days estimates by at least 2 or 3, because in many (most?) places the times when power failures are most likely are also the times when households need the most electricity. For example here in western Washington outages are most likely during winter, which is also when we are using the most electricity. My daily winter use is 3.5-4 times my daily summer use, perhaps even more on those years when we get a week of near record cold.
totetsu 3y ago
>"random Pacific islands aside" kind of dismissive..
- myself248 3y ago
  Islands tend to have good sun exposure, minimal cloud cover, and little in the way of alternatives. Of course they do solar there. Doing solar in places that perhaps aren't as sunny, and which could easily connect to a grid, is newsworthy.
conductr 3y ago
Some of the Bluetti home power stuff looks nice to me as an individual and not requiring any community cooperation. It’s not as sleek as a power wall but I have space for it https://www.bluettipower.com/collections/home-battery-backup https://www.bluettipower.com/collections/home-battery-backup
- antisthenes 3y ago
  Things like that are incredibly overpriced, you're paying almost $1000 per KWH of capacity.
xbmcuser 3y ago
The price of 50k per house will probably be 25-30k in 5 years.

hkt 3y ago

It'd become much more sustainable to do what you're talking about if it was accompanied by energy saving measures. Do it well and you could easily aim for 5kWh per day per house by minimising heating and cooling choices.

momirlan 3y ago

anker, being a Chinese manufacturer, doesn't have much chance to penetrate the western markets. even assuming they can develop a dependable product. but I wouldn't trust more than a headphone, or a wall charger from them.

vorpalhex 3y ago
Anker knows batteries and their LiFePO4 batteries are solid stuff (as are their traditional lithium cells). Even if you prefer a US maker, competition will help lower prices.
mschuster91 3y ago
I agree on being careful with China goods in general, but Anker is one of the very few very trustworthy brands out there. IIRC, the only fuck-up regarding batteries they did was with the 535 power banks, and they handled that one very solidly [1]. [1] https://www.cnet.com/tech/computing/anker-recalls-some-535-power-banks-over-fire-risk/ https://www.cnet.com/tech/computing/anker-recalls-some-535-p...
- mschild 3y ago
  Unfortunately, no they're not. Anker owns Eufy and they had some massive issues. https://www.digitaltrends.com/home/anker-admit-eufy-security-issues/ https://www.digitaltrends.com/home/anker-admit-eufy-security...
croes 3y ago
Pretty strange view, when you consider that China still is the workbench of the world.
- momirlan 3y ago
  lol

s_tec 3y ago

I recently installed an Enphase home backup system as a DIY project (crazy, I know). The biggest problem with any home-backup system is moving the loads onto their own sub-panel. When the utility goes down, power needs to flow into the home, but not to the rest of the neighborhood. To do this, a switch needs to physically disconnect the utility meter from the main loads panel. If this isn't possible (such as when the meter is integrated into the panel), all the loads need to move to a sub-panel. This is the hard part. Once the meter and main panel are separate, the various backup solutions become pretty similar. The disconnect switch installs between the two, with the solar and battery attached. Sometimes the disconnect switch + solar + battery are all in one unit (like the Bluetti EP900), while sometimes the solar inverter, battery, and switch are all separate units (like Tesla or Enphase). The Tesla switch and battery are sleek & glossy, but the inverters are ugly. The Enphase stuff isn't quite as shiny, but at least the boxes look consistent. Performance-wise, the systems seem pretty similar as well. Most systems are around $10K for 10KWh of capacity, with somewhere around 6-9 KW of peak discharge rate. I imagine these prices will drop a lot over the next decades. If the battery becomes obsolete, just install a different system. Once the home is correctly wired, swapping the storage system should be pretty straightforward.

rstupek 3y ago
Why did you choose the Enphase system versus any of the others? How much capacity did you install and is it upgradeable?
- s_tec 3y ago
  I like the distributed architecture. Each solar panel has its own inverter, as well as each battery. If I want more panels or batteries, I just add them in parallel with the existing panels or batteries. If a panel or battery goes down, the remaining ones keep working. Avoiding high-voltage DC also makes the project more DIY-friendly. The downside is that Enphase requires users to take online classes before they grant access to the installer app (easy but time-consuming). Right now I have 3.8KW of solar and a single 3.3KWh battery. We are producing more than we use most months, so the solar is good but the battery is undersized. If we have an extended grid-down scenario like what happened in Texas, the system will mainly provide daytime backup plus a few evening hours. This is still better than nothing, and we can easily add more batteries as we have the budget.

maliker 3y ago

Pair the storage with some solar, and you could probably reduce the storage size or increase the survival duration (or both). Here's a fun tool that lets you play around with the balance of these things and see the expected cost: https://reopt.nrel.gov/tool https://reopt.nrel.gov/tool

adql 3y ago

> Probably not worth it and I'd expect 3 days to be overkill. But a community that was double our size will have a cost of about 25k per unit for 1.5 days of power - which doesn't sound too bad to me. If you're not looking to go completely off-grid, I think you want to double it again. At basic level, battery pack is there to soak solar power during a day and give it off when the solar is down. 16 hours is enough to cover most or all of that.. I think the model could work if the local community basically "sold" the battery storage capacity to the users. Pay few cents for kWh to store it for 24 hours, anything in excess can be sold back to residents at slightly lower than market price, producing some money for maintenance and upgrades.

nuancebydefault 3y ago

I never stop to be amazed how average consumption figures in the US are often at least 100 per cent bigger than in Europe. At least for water and electricity, let alone fuel. Just a thought that naturally pops up... : If you take the reasoning one step back, wouldn't it be easier to optimize the consumption side (low hanging fruit) in favour if optimizing the cost per unit of energy? The latter seems a lot of effort, at least for the devs.

cultofmetatron 3y ago
its pretty easy to understand when you spend significant time in both. european cities: typically built for density. I'm never more than a 10 minuite walk to a grocery store. I can hop on a train or tram to get to work and I can usually stop to get groceries for the day on the way. if you're in a city like athens, you can get fresh fish and meat. was probably dreaming of finding a mate or eating fresh acorns on the other side of the pasture barely a day ago. USA: Its a hellish landscape of urban sprawl. want to get sone milk or eggs? its illegal in most place for there to exist a grocery store within walking distance. be prepared to walk along the side of a busy road to get to a convenience store which might have what you are looking for. maybe there's a sidewalk if you're lucky. Every damn trip requires a car. your work place is probably 30 min drive minimum. there is no other way to get to work. since getting to the store requires effort, you're going to go get a week's worth of groceries to save time. fresh meat? nah, killed weeks ago in a centralized slaughter house and shipped accross the country after a life of being fed corn farmed with chemical fertilizers and shipped to the animals in temperature controlled facilities. better keep a large fridge to hold it all. wouldn't want it to spoil before you eat it. you literally can't live in the USA without increasing your consumption. its built into the dna of our infrastructure.
- zamfi 3y ago
  Neither Europe nor the USA are a monolith in this regard. Live in NYC or even S.F. and you can 100% walk to the store and take transit to work. Live in rural or suburban Germany and you’re driving everywhere.

oh_sigh 3y ago

Realistically you could get that number 6x smaller, because people could voluntarily cut their usage from 30kwh to 15 when the power is out, and 1.5 days of power is probably overkill when 12 hours would get you through 99% of power out scenarios in America. On top of that, when the grid is functioning normally, you could use the batteries to get cheaper electric rates with time of use pricing.

pests 3y ago

Surely doubling the households would only half the cost or the duration available, not both?

HeyImAlex 3y ago
I don’t think so? Household Cost = Total Cost / Households, Household Duration = Capacity / (Household Usage * Households), Houshold*2 would half both.
- pests 3y ago
  Oh duh, right. Thanks.

mshenfield 3y ago

25k per unit, assuming the battery lasts 5 years, is uneconomically high at $5k/year per home. A 100kw generator can produce enough power for 100 homes, costs ~$50k all in, and ~$1k per day in fuel costs to run during an outage. Assuming the generator also lasts 5 years, that's only $100/year per home, 50x less than the battery solution. Batteries are for the foreseeable future way too expensive.

tzs 3y ago

You probably should divide all those number of days estimates by at least 2 or 3, because in many (most?) places the times when power failures are most likely are also the times when households need the most electricity. For example here in western Washington outages are most likely during winter, which is also when we are using the most electricity. My daily winter use is 3.5-4 times my daily summer use, perhaps even more on those years when we get a week of near record cold.

totetsu 3y ago

>"random Pacific islands aside" kind of dismissive..

myself248 3y ago
Islands tend to have good sun exposure, minimal cloud cover, and little in the way of alternatives. Of course they do solar there. Doing solar in places that perhaps aren't as sunny, and which could easily connect to a grid, is newsworthy.

conductr 3y ago

Some of the Bluetti home power stuff looks nice to me as an individual and not requiring any community cooperation. It’s not as sleek as a power wall but I have space for it https://www.bluettipower.com/collections/home-battery-backup https://www.bluettipower.com/collections/home-battery-backup

antisthenes 3y ago
Things like that are incredibly overpriced, you're paying almost $1000 per KWH of capacity.

xbmcuser 3y ago

The price of 50k per house will probably be 25-30k in 5 years.