This battery uses a safer type of lithium chemistry that is less prone to overheating, though no large battery is risk-free. Water is used by firefighters to cool battery fires (they can reignite tho).
Install it outdoors or in a detached garage, away from anything flammable. Never in a bedroom, hallway, or escape route.
There are newer batteries tech that can't inflame.
Most modern batteries like this are weatherproof and can be mounted outside the home. Most modern batteries use LiFePO4 chemistry, which while not perfect, is much less risky in terms of thermal runaway than older lithium ion batteries.
The Tesla Powerwall is only slightly larger than a pizza box and can be mounted directly on the wall. Most of the below images are outside the house, but some are also in the garage.
I have two Powerwalls mounted on my house and while I think they're fantastic and pretty compact for what they are, I would not describe them as anywhere near the size of a pizza box (unless you mean one of these things [1]).
> Create a battery birthday club. Buy each friend a battery on their birthday until everyone has one.
At that point, wouldn't it be easier if everyone just bought their own? And then whoever has the latest birthday doesn't have to wait a year to get theirs.
It is like an energy storage cost cutting rotating potluck. blitzar mentions bulk buying in a comment, which is a great idea to drive down cost. Not sure what the EU version of that looks like, the US versions are:
Europe has quote a bit of renewable generation currently that is curtailing or otherwise going unused, and needs all of the battery energy storage it can get (residential, commercial, utility scale) to convert curtailment into realized clean energy offsetting potential fossil energy usage (fossil gas in most of Europe, coal in Germany and Poland, as Portugal, Spain, Ireland, and the UK have already phased coal out).
> Hundreds of millions of solar panels have been installed in Europe, turning solar into the region's biggest source of power during summer months, but the system around it hasn't kept up. A record amount of electricity is being wasted because grids can't handle the surge in output, with about 40 terawatt-hours of electricity expected to go to waste in the coming months. The glut of solar power is pushing power prices deep below zero during peak solar hours, eroding returns for producers and forcing them to shut down plants, with consumers potentially paying twice for the subsidies and compensation.
Yes, but I think the missing ingredient is that building societies "bid" to decide who gets to go first. Whoever is willing to take the smallest loan/pay back fastest gets preference.
Reinventing building societies seems very cool to me -- it's a little more nuanced than the birthday thing, but it's a system that can work with assets that generate value.
I've heard of people doing this kind of rotating "Everyone pays $X in each week/month, a different person decides how to spend it each week/month" thing. It's mostly for building social connection/community.
In Germany you can use a "Balkonkraftwerk" that just plugs into any outlet and contributes up to 800W. You can also hook up solar panels to it up to 2000W (makes most sense with batteries). No need for the landlord to agree.
You're getting downvoted, but for real this is so disconnected from what I'd say is feasible for most people. I and most of the people I know live squarely paycheck to paycheck, I can't afford to buy my friends birthday presents at all, let alone set aside that much per month just to put batteries in other peoples' houses. This feels like one of those things where the author doesn't grasp the privilege he lives with.
Surely not for _most_ people, but for people on Hacker News, in the correct age range to have a house, putting 100e aside really does not seem out of whack.
Maybe the author is privileged and it's fine, it's not because you personally can't afford any gift that the author is disconnected, he might not just be talking to everyone on earth.
I think the people that can easily put aside €100 for the birthdays of a dozen or more friends could also just pay the €1600 and buy the battery for themselves outright without having to wait for a birthday "surprise"
Yeah, strip away all the decor and it's trying to convince every person to lend €1600 (~$1850 USD) that year to a loose circle of friends in the hope that they'll get a €1600 battery back somehow.
Why can't renters plug a battery into their socket, too? As long as the electric house grid is rated for the specified power (might not be the case on some countries, or in extremely old homes).
I'm not an expert. But a Tesla Powerwall type battery is a big thing to install for a renter, is it not? I would argue it's more than installing, say, a washer or window AC; probably more like installing a wall heat pump?
You would certainly need the owner's permission, and investing in the kind of adaptations needed might not be something most renters are interested in when it's not their own place. A battery has to be integrated into the whole electrical feed, and a responsible owner might insist that this is a permanent installation and something you can just take with you when you leave. Or if you do, undoing the install will be similarly costly. And who knows if your next place will allow you to install a battery as well.
I don't think you can realistically install it in an apartment, due to fire regulations, and it needs a lot of space. Personally, I live in a 74 m2 apartment, and there's simply no room anywhere. Wiring is another matter; electricity comes through shared risers I don't control.
I'm not an expert here, but I don't think you're supposed to backfeed electricity into your panel while you're connected to the grid. Doing something like this (historically at-home solar) you'd need a way to disconnect from the grid physically, at least if you wanted to reuse your home wiring.
Now, you could use the battery as a pass through power source, but then you'd have to change all the wiring in your home.
And everyone makes enough money that something going wrong with their €1600 payment/expectation isn't going to ruin relationships.
It might not actually be "buy one-another new cars" territory, it's closer to that than paying for your friend's coffee or buying an appetizer for the whole table.
> You are also safer during a power outage. The STREAM 5000 provides up to 3 kW of off-grid output. Keep essential devices on its backup output and reserve some battery capacity, and your refrigerator, lights, router, and laptop can keep running when the grid goes down. An ordinary grid connection does not back up the whole house automatically; the backup output must be configured correctly.
Being able to cut over your entire house from grid power to a battery is an incredibly invasive, expensive procedure. I wish people would stop breathlessly promoting batteries (which are good! we need decentralized storage!) because "you can use them to run your fridge, router, etc". Yes you can, but for almost all consumers it's an order of magnitude more effort and cash compared to just buying and plugging in a battery.
I disagree. During an outage, you need your fridge and a few other essential items. A novice can plug into the back. The device tells you the load and whether you are exceeding. And you can test it at any time. For $600 you can get started without an electrician.
it's the easiest, safest , most affordable and most reliable emergency solution ever available.
I really get where you're coming from, but I'm approaching this from the ~$1500, 5 kWh battery in TFA, which weights 50-60 kg, should be installed somewhere out of the way in a non-fire-hazardous manner. They're great, they can load-shift a meaningful chunk of daily consumption for most european homes don't just move these around to your freezer. They don't magically make you independent in case of grid failures, it's just not what they're for. And to get the average consumer to adopt these, the messaging about what they can and can't do should be crystal clear.
Not necessarily the point. If it provides a normal wall outlet I'm happy to plug essentials around for the one time per 1-2 decades this happens for longer than 4 hours and the fridge/freezer/laptop needs a boost
As long as you're not opening the fridge / freezer during the outage (and you have sufficient thermal mass of food in it) you don't need to worry about "boosting" it during a power outage of only 4 hours. I don't recall the rule of thumb off the top of my head, but for at least 6 hours I'd expect the contents of normal fridge / freezer to be just fine (as long as there's thermal mass there).
Yes, thanks, indeed I'd start doing this *after* 4h if I have such a battery since fridge, freezer, and laptop are all in different places and they'll run for 90 minutes to cool or charge and it's probably not bad to get around to all towards the end of the first day with no stress. It was just an arbitrary starting point really. Freezer contents are also all fine after 24h but maybe some edges got towards the thawing point. I've not tried it out and simply wouldn't care to find out
The issue there is the plug would be on the battery which you're unlikely to have mounted in a convenient location for things like your main fridge, router, and computer. For me all 3 of those are pretty far away from the most likely places I'd put a battery bank.
Ah, right I was picturing an oversized car battery that you can lug around. Extension cord then? Not sure but this seems surmountable without having to rewire the house and get a permit or licensed unit for feeding the grid
The size the article is talking about are usually around 100 pounds or ~50kg at least. My solution is the much smaller Anker Solix C1000 and it's outboard battery extension. It can output up to 1800W sustained with a 2.4 KW peak and the two units together have about 2100 Wh of capacity. They're small enough to move around by hand when disconnected but can't do the kind of peak shifting the OP article was talking about so they're purely backup or car camping power. I used them to power my WFH setup while my electrical service was being upgraded a while ago though and it worked well enough.
I dunno. TBH I'd rather just let the food go bad than bother with the expense and hassle of having a battery and keeping it charged. I guess other locations may have less reliable grids than I do, but I've only experienced one power outage that lasted so long[1] that our food went off in my entire 40 years living in the Twin Cities area.
[1] About 96 hours, major storm took down a ton of trees through the whole metro area that took days to clear.
I can't even remember the last power outage we had that was not self-inflicted (a year ago our old microwave oven permanently tripped the residual current device).
Also, according to the article, it seems to pay itself back in 11-12 years. I'd rather pay the little extra to not have a huge lithium battery in our appartment that cannot be extinguished with a normal fire extinguisher if it decides to ignite itself.
The device's primary use would be using excess solar power from during the day, or excess wind on rare occasions. This would just be a nice benefit and I just meant that it doesn't have to keep up with the whole house during an outage to still help out in a pinch
Must be nice. I live in Virginia, outside Richmond. For the past 8 years, the power company has failed to provide me with even 3 nines of power availability (that means at least 9 hours of outage every year for the past 8 years. Just had a 17 hour outage as of last night, lost everything in my fridge. Again.)
And the proposed battery solution only works at up to 3kW. My electric range uses more than that, and my water heater, clothes dryer, and aircon each come close.
And, sure: I can get by very well with refrigeration, networking, computing and/or TV, and lights during a power outage. But those loads need to be segregated, or it just doesn't work. That adds more expense.
And since those segregated loads don't even come anywhere near 3kW, it isn't clear to me how I'm to be maximizing my local use of surplus power events.
There are grid-interactive battery solutions from companies like from EG4 that can go betwixt the entire house and its grid connection, but this isn't it.
The cost/invasiveness of cutover is dropping. There is a relatively new category called "plug in solar" where the inverter/battery is smart enought to detect, sync and use grid power.
The Stream system: Connect the device to the grid to enable it to feed power into the grid or draw power from it when solar energy is insufficient. This can be done via a standard home outlet (if permitted), or through a circuit breaker. [0]
I mean, yes and no. Switching your whole house over automatically? Yeah, ok, that can get invasive and expensive. Running an extension cord from a battery/inverter or generator a multiport plug then to to your fridge, router and a couple of lights? That's about 5-10 minutes of effort.
There's a pretty massive middle ground between "plug in a battery" and "rewire the house.
Switching the whole house is cheap compared to the generator or battery needed to run everything in the house. Of you can't run everything then you may as well have nothing. The important things need a lot of power.
I'd imagine most electric car batteries aren't fully charging and discharging every day. That makes quite a bit of difference in wear!
Tons of EVs these days are being made with what, 200-300mi range of battery pack with some internal buffer as well so they're never really going 0-100%? So what, we'll be generous here about the 20-80% and think 160mi of range used every day. That's 58,400mi of driving per car! The average US car does closer to 14,000mi. Being generous, that's 4x the wear cycles of a normal US automobile.
Eh, there’s a tension there, becuase on the other hand as more renewable power is added to the grid, you’d expect divergence. Especially in countries which are letting people buy at spot price; that can be horribly expensive, or go _negative_.
You don't necessarily need to export power, especially for a small battery like tihs. Charge it up when power is cheap, and then configure it to discharge when power is expensive but only to match your current usage. You will need a CT on your main feed for it to balance against, but it can be done.
Call me old fashioned, but I just bring a can of gasoline and a pile of super soakers.
While I do like the idea in theory, I don't love the inherent nudge towards off the shelf productized energy storage that will be placed somewhere without much of a plan, and then basically invites rewiring with extension cords. I get how those things are appealing for camping or determined apartment DIYers at the like, but moving them from a seek-them-out "pull" dynamic to a here-you-go "push" dynamic seems like asking for problems from people not thinking too much about storing 5kWh.
You don't really need this, if you have an EV with V2X technology. There's already charging products that work seamlessly: https://www.youtube.com/watch?v=H0WGl_U5azs and you have 100kWh of capacity, so you could sit out an outage for a long time. You can also configure the % cut off for the EV, so you still have enough left to drive if you need to leave.
EV battery degradation from this use case is irrelevant. EVs are consistently hitting 300,000 miles with 90% capacity, so let's not belabor this point.
The thing about the EcoFlow Stream is that has things like phase alignment which allows it to be plugged directly into a household outlet without transfer switches to segregate grid phase from the phase of power created by the V2X inverter's phase. It also handles solar input.
I suppose that future V2X systems will incorporate direct plug-in tech, but note the transfer switch used by the system in the video.
11-13yr payback on something that is going to degrade ~3-4%/yr for 10 years (and limited terminal value) doesn't seem like the greatest investment unless you think the arb is going to widen a ton.
And any arbitrage is also trivially exploited by the electricity company, who has a much greater financial incentive and scale, so there's really no reason to think that it's going to widen in the future either.
You could exploit it yourself, but only if you have several million to invest, less than that and it isn't worth the bother for the electric company to talk to you. Even at ten million invested you really need to have this is round one in your proposal with the understanding you intend to invest a lot more when it proves in the real world to work like you expect.
Until grid-scale batteries are more established, you're helping the electric company, and that's why they're exposing the arbitrage. They're providing the incentives to nudge demand, so a home battery is doing exactly what they want (use more at time X, use less at time Y). Otherwise they'd just have the 24/7 price be whatever it currently costs when the supply and demand curves are tightest for them (when demand is highest and/or supply is lowest).
Let's assume the calculation is correct and you actually earn back in 11-13 years. You are better off investing the money in something like the S&P 500 where you'd double your investment in about a decade without the hassle.
Things will start to get interesting where €1600 don't buy you 5kWh but double or triple the amount.
I can imagine most people are better off either investing like I said or in insulation.
Alternative systems are closer to 5 years payback if you have access to off peak energy. 3-4%/year degradation is very high, battery packs available in the UK from Fogstar are rated at 8,000 cycles with a 95% depth of discharge.
FWIW my high voltage battery pack has almost 365 cycles and is still at 100% state of health.
Add in that my freezer probably contains over $500 of food (and the fridge has less, but not none.)
Usually you can buy ice, but when I had a ~36 hour outage a couple years ago, I couldn't. Most stuff was fine for that long, but 2-3 days would've meant tossing pretty much the entire contents.
(Plus, I don't have cell service where I live, so being able to power my router is pretty useful.)
This is probably a bad move if you live in a city. It makes more sense in rural areas.
At my mother's workplace, there was a group of coworkers who each donated an amount of money per paycheck. Each paycheck, one coworker would get the lump sum that was collected for that paycheck. Similar concept to the one described here. They called it "susu" or something to that effect. If I remember correctly, it got messy when people would leave the workplace or when, occasionally, someone would get robbed on the way home.
I read the book Poor Economics[0] around when it came out, and it described something similar.
For people who don't have access to banks, they form "savings clubs" where there will be, say, 12 people who put in $100 per month, and one person takes the pot every month. The idea is that if you keep the money yourself, then you're socially pressured to spend it when there are holidays or guests, but if it's locked up in the savings club, you can't spend it, and then you get a big lump sum to spend on a large purchase that would be otherwise hard to save for.
People don't tend to buy people large furniture because it's rude to assume that theyll want to keep something large and relatively permanent, much less something that requires an electrician to install.
So I could buy a battery for ~$1,850 today that won't even break even in a decade (and hope everything goes well with this plan, not guaranteed in the slightest), or I can buy a 10 year US treasury bond that'll give me another $1,000+ in profit at the end of the decade.
Remind me why I should buy the battery? It clearly can't be because it makes financial sense to just have the battery.
I don't think installing this kind of system at home is a good idea, especially considering the risk of fire. The amount of energy contained in a 5 kWh lithium battery is terrifing.
There are numerous systems available for this type of system that are professionally designed and built, and satisfy all kinds of local codes.
Many are in use all over the world in off-grid cabins and similar.
You do need to take care that they are installed correctly, and maintained properly, but that isn't much different than a natural gas connection, or even normal everyday electricity.
Strange article, even though the idea is nice. $200 birthday presents might be a thing in America in some circles, but for German standards that is ludicrous (even 50 bucks is quite a lot, and then you need 32 people).
I also don't get his example calculation. He mentions that average price in Germany is 38c/kWh, but in the table it's suddenly 4c min vs 13c max (or 40 vs 133?). That doesn't compute.
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[ 0.28 ms ] story [ 6.8 ms ] threadWhere do people store these things? They're very dangerous once afire! Worse than a can of petrol by far and can't be extinguished with water.
Install it outdoors or in a detached garage, away from anything flammable. Never in a bedroom, hallway, or escape route.
There are newer batteries tech that can't inflame.
https://duckduckgo.com/?q=tesla+powerwall&ia=images&iax=imag...
[1] https://www.scottspizzatours.com/blog/worlds-largest-deliver...
At that point, wouldn't it be easier if everyone just bought their own? And then whoever has the latest birthday doesn't have to wait a year to get theirs.
https://solarunitedneighbors.org/
https://www.brightsaver.org/
Europe has quote a bit of renewable generation currently that is curtailing or otherwise going unused, and needs all of the battery energy storage it can get (residential, commercial, utility scale) to convert curtailment into realized clean energy offsetting potential fossil energy usage (fossil gas in most of Europe, coal in Germany and Poland, as Portugal, Spain, Ireland, and the UK have already phased coal out).
https://beyondfossilfuels.org/europes-coal-exit/
Solar Power Is So Big in Europe That Electricity Is Being Wasted - https://www.bloomberg.com/news/articles/2026-05-13/europe-so... | https://archive.today/nAdiA - May 12th, 2026
> Hundreds of millions of solar panels have been installed in Europe, turning solar into the region's biggest source of power during summer months, but the system around it hasn't kept up. A record amount of electricity is being wasted because grids can't handle the surge in output, with about 40 terawatt-hours of electricity expected to go to waste in the coming months. The glut of solar power is pushing power prices deep below zero during peak solar hours, eroding returns for producers and forcing them to shut down plants, with consumers potentially paying twice for the subsidies and compensation.
You may not have £100,000 but if you get 1000 people with £100 then you can buy a house.
Obviously the birthday system doesnt address the interest, but I'm sure your friends would be ok paying interest right?
Reinventing building societies seems very cool to me -- it's a little more nuanced than the birthday thing, but it's a system that can work with assets that generate value.
yeah sure everyone has 100€ to spend on friends, at least once a month.
What kind of reality does he live in ?
Maybe the author is privileged and it's fine, it's not because you personally can't afford any gift that the author is disconnected, he might not just be talking to everyone on earth.
You would certainly need the owner's permission, and investing in the kind of adaptations needed might not be something most renters are interested in when it's not their own place. A battery has to be integrated into the whole electrical feed, and a responsible owner might insist that this is a permanent installation and something you can just take with you when you leave. Or if you do, undoing the install will be similarly costly. And who knows if your next place will allow you to install a battery as well.
I don't think you can realistically install it in an apartment, due to fire regulations, and it needs a lot of space. Personally, I live in a 74 m2 apartment, and there's simply no room anywhere. Wiring is another matter; electricity comes through shared risers I don't control.
Now, you could use the battery as a pass through power source, but then you'd have to change all the wiring in your home.
It might not actually be "buy one-another new cars" territory, it's closer to that than paying for your friend's coffee or buying an appetizer for the whole table.
Being able to cut over your entire house from grid power to a battery is an incredibly invasive, expensive procedure. I wish people would stop breathlessly promoting batteries (which are good! we need decentralized storage!) because "you can use them to run your fridge, router, etc". Yes you can, but for almost all consumers it's an order of magnitude more effort and cash compared to just buying and plugging in a battery.
https://duckduckgo.com/?q=Uninterruptible+power+supply+refri...
it's the easiest, safest , most affordable and most reliable emergency solution ever available.
[1] About 96 hours, major storm took down a ton of trees through the whole metro area that took days to clear.
Also, according to the article, it seems to pay itself back in 11-12 years. I'd rather pay the little extra to not have a huge lithium battery in our appartment that cannot be extinguished with a normal fire extinguisher if it decides to ignite itself.
Winter storms tend to come in cold stretch’s that can cause major freeze havoc.
And, sure: I can get by very well with refrigeration, networking, computing and/or TV, and lights during a power outage. But those loads need to be segregated, or it just doesn't work. That adds more expense.
And since those segregated loads don't even come anywhere near 3kW, it isn't clear to me how I'm to be maximizing my local use of surplus power events.
There are grid-interactive battery solutions from companies like from EG4 that can go betwixt the entire house and its grid connection, but this isn't it.
The Stream system: Connect the device to the grid to enable it to feed power into the grid or draw power from it when solar energy is insufficient. This can be done via a standard home outlet (if permitted), or through a circuit breaker. [0]
0. https://manuals.ecoflow.com/us/product/stream-ultra?lang=en_...
There's a pretty massive middle ground between "plug in a battery" and "rewire the house.
Who says? Say I need my fridge, freezer, router and a light or two. That's $4k. Whole house? $25-35k.
Also, I have a wood burning stove and piles of firewood).
It seems australia has very low friction
and US with our power companies, significantly more
- where you going to find an electrician?
- do you need someone to design your grid-tie plan?
- when will the power company approve your connection?
I've had friends wire their house, have to really work to plan the setup, and be stuck with a working system offline while PG&E approves slowly
Another point: People might be better served NOT buying a battery, instead getting an EV and wiring it into their house.
for example: https://www.tesla.com/powershare/
or just "bidirectional charging" for other brands
If you only cycle then in the 20-80% range, they'll last much longer (at least for NMC cells, not sure how LFP works).
Tons of EVs these days are being made with what, 200-300mi range of battery pack with some internal buffer as well so they're never really going 0-100%? So what, we'll be generous here about the 20-80% and think 160mi of range used every day. That's 58,400mi of driving per car! The average US car does closer to 14,000mi. Being generous, that's 4x the wear cycles of a normal US automobile.
This seems like the hardest step. The costs of "just a battery" are much lower by comparison.
(plug-in batteries aren’t actually legal here yet, but likely to become so next year!)
While I do like the idea in theory, I don't love the inherent nudge towards off the shelf productized energy storage that will be placed somewhere without much of a plan, and then basically invites rewiring with extension cords. I get how those things are appealing for camping or determined apartment DIYers at the like, but moving them from a seek-them-out "pull" dynamic to a here-you-go "push" dynamic seems like asking for problems from people not thinking too much about storing 5kWh.
Those prices are high. You can get 2.56kWh for 270€ on Aliexpress, delivered locally from Germany.
What could possibly go wrong? The things that people do.
Personally, I'd like the company to be in the EU so that I can at least sue them if it burns down the house.
There are even cheaper ways of starting a fire.
EV battery degradation from this use case is irrelevant. EVs are consistently hitting 300,000 miles with 90% capacity, so let's not belabor this point.
Nope.
I suppose that future V2X systems will incorporate direct plug-in tech, but note the transfer switch used by the system in the video.
Gift should be ... gifts
Things will start to get interesting where €1600 don't buy you 5kWh but double or triple the amount.
I can imagine most people are better off either investing like I said or in insulation.
The investment point still stands, though you could argue both come with risk/reward, energy prices aren't guaranteed to be stable.
FWIW my high voltage battery pack has almost 365 cycles and is still at 100% state of health.
Usually you can buy ice, but when I had a ~36 hour outage a couple years ago, I couldn't. Most stuff was fine for that long, but 2-3 days would've meant tossing pretty much the entire contents.
(Plus, I don't have cell service where I live, so being able to power my router is pretty useful.)
This is probably a bad move if you live in a city. It makes more sense in rural areas.
For people who don't have access to banks, they form "savings clubs" where there will be, say, 12 people who put in $100 per month, and one person takes the pot every month. The idea is that if you keep the money yourself, then you're socially pressured to spend it when there are holidays or guests, but if it's locked up in the savings club, you can't spend it, and then you get a big lump sum to spend on a large purchase that would be otherwise hard to save for.
[0] https://en.wikipedia.org/wiki/Poor_Economics
The whole system is.. not great, but it's even cheaper to have a battery than this post makes it sound.
Remind me why I should buy the battery? It clearly can't be because it makes financial sense to just have the battery.
Many are in use all over the world in off-grid cabins and similar.
You do need to take care that they are installed correctly, and maintained properly, but that isn't much different than a natural gas connection, or even normal everyday electricity.
I also don't get his example calculation. He mentions that average price in Germany is 38c/kWh, but in the table it's suddenly 4c min vs 13c max (or 40 vs 133?). That doesn't compute.