11 ms·

Battery-swap networks are preventing emergency blackouts

136 points by belter 2y ago

neallindsay 2y ago
There's lots of talk about grid-scale batteries to shift cheap electricity from solar panels into the night time. But batteries at the periphery can also help a lot because they can just stop charging (like the example in this article) or even feed energy back into the grid. Electric cars mostly don't have the circuitry to do this yet, but they're becoming a huge resource that will be tappable this way. Most of them are massively over-provisioned for the way that they're used 350 days out of the year.
- t_tsonev 2y ago
  On-demand charging is very much happening today. All chargers communicate the available charging current with the vehicle and some can adjust it dynamically. As for control, there are proprietary and OSS solutions (shout out to https://evcc.io/en/ https://evcc.io/en/) that allow you to control the charging process based on price, grid load, local PV generation, etc.
  - ckdarby 2y ago
    I see the basic version of this already with the Tesla vehicles where if you plug in another appliance on the same breaker the car will decrease its draw to prevent triggering the breaker.
    - cesarb 2y ago
      > where if you plug in another appliance on the same breaker the car will decrease its draw to prevent triggering the breaker. That's alarming. There's no way the car can know that there's another appliance on the same breaker. The only way it can know it should decrease its power draw, is by detecting that the voltage decreased on the circuit, but that voltage decrease will only be noticeable if the wiring is undersized for the load (in fact, that feature is probably designed to protect against overheating undersized wiring on the circuit feeding the car). That circuit is probably severely overloaded, which can be a fire risk.
      - jeffbee 2y ago
        This feature doesn't exist. The Tesla home charger can share current with other Tesla chargers on the same branch. It can't share current with an electric water heater or some other non-Tesla load
        Retric 2y ago
        I think the OP was just confusing a feature used by someone with a Tesla from a Tesla specific feature. They might be using one of these: https://www.chargedfuture.com/240v-outlet-smart-splitter/ https://www.chargedfuture.com/240v-outlet-smart-splitter/ There’s also smart breaker boxes that again have nothing to do with Tesla specifically. The breaker box will preferentially shed EV charging first when someone would otherwise trip their whole homes’s connection to the grid. It’s not a perfect solution, but sometimes your local utility doesn’t want to upgrade your connection to the grid because their substation is fully provisioned or whatnot.
- rthomas6 2y ago
  I wish it were standard practice to have some kind of house battery (what Tesla calls "Powerwall") for new construction homes. They could smooth out peak usage in this exact way, in addition to making individual homes more resilient to occasional power outages.
  - practicemaths 2y ago
    It might happen! There's a fair bit of active research into repurposing batteries from cars into such a purpose or similar. This both extends the usefulness of the manufactured good (the battery) while also hopefully lowering the upfront costs of new electric cars.
  - adgjlsfhk1 2y ago
    IMO this isn't the direction we're going. I'd bet that in 20 years, there will be some form of grid-scale specific battery that is 2-3x cheaper than lithium iron (per joule), but with much worse energy density. Many of the batteries of this type are unsuitable for home installation (because they get more efficient with scale). Some of the potential options for this are things like iron sulfur batteries which require pretty high temps, or some designs for batteries that basically involve physical pumps to pump liquid anodes and cathodes around.
    - szvsw 2y ago
      > some designs for batteries that basically involve physical pumps to pump liquid anodes and cathodes around Yeah in addition to flow batteries there are also grid scale thermal batteries, though these are targeted more towards long duration energy storage: run electricity through a large carbon block in a shipping container form factor to heat it up, then use infrared photovoltaics to convert back to electricity when desired.
      - Teever 2y ago
        I'd be interested in learning more about this carbon block battery that you're describing. I'm also curious how it compares in cost effectiveness to this battery that's based on sand. https://tambaynews.blogspot.com/2022/07/worlds-first-commercial-sand-battery.html https://tambaynews.blogspot.com/2022/07/worlds-first-commerc...
- mauvehaus 2y ago
  Green Mountain Power does exactly this in Vermont: they have a program that'll install a pair of powerwall batteries at customer homes and charge them off peak to draw on them on peak, particularly to avoid GMP having to buy peak-rate power from their upstream suppliers. In return, they leave the batteries charges when the weather is turning bad and the customer has battery backup. The deal is structured as a 10 year lease, and the total cost is vastly less than that of owning the batteries outright. Their installation allowance is pretty good too; it didn't cover splitting our panel, but it covered everything else. Not affiliated other than being a very happy GMP customer.
  - onionisafruit 2y ago
    You say they leave the batteries charged when the power is turning bad. Do you have a benefit of hosting the batteries at other times? For instance if the power goes out when the weather isn’t bad, do you typically have enough charge to make it through the outage? I’m also curious if your neighbors benefit from your battery during outages.
    - mauvehaus 2y ago
      De jure, I think they're pretty free to do with them what they want. De facto they leave the batteries pretty fully charged most of the time. AIUI, they'd have to have a disconnect somewhere upstream of us to let us back feed the grid during an outage, otherwise they couldn't safely work on the lines. And they'd need a way to enable and disable back feeding remotely[0] to allow them to work on anything between that hypothetical disconnect and us. At the moment, none of that exists, so only we benefit from the powerwalls. It's also 34kwh in the pair of batteries. That wouldn't add up to too many household-days if you started adding households. You'd have to do some fancy switching to not overwhelm the relatively few powerwalls in an outage. For context, based on our usage, we're at about three days of backup just for us [1]. It doesn't take much imagination to come up with a scenario where that happens where we are. We are the very last pole. [0] Which in turn requires connectivity. The cell network here is sparse, to put it mildly. We just got fiber, but that's hanging on the same poles as the power. The fail-safe mode for no grid and no connectivity is to not backfeed, but at that point, you're back where you are today. [1] It's the fridge, mostly.
- pfdietz 2y ago
  Even lower hanging fruit would be increasing the dispatchability of demand in homes. Simply allowing heating and cooling to be dispatched would be very helpful. In the past this was done with bespoke add-ons to furnaces and AC compressors, but now it's done with smart thermostats.
  - smileysteve 2y ago
    Dispatched versus random dither are similar; For most smart thermostats, one of the lesser known quality improvements is the 5 minute + dither time for startup. This is designed for compressor health - but prevents repeat cascading brownouts - where programmable thermostats or manual thermostats would have either a strict 5 minute wait time or none at all. Other features like time of use, humidity correction, and fan circulation also drastically reduce energy usage.
    - hedora 2y ago
      Our thermostat seems to apply the delay even when you manually turn it on. It drives me nuts. (After a power failure or during scheduled transitions make sense; after I push the button: not so much.)
  - immibis 2y ago
    ISTR they did this somewhere (getting a discount on power in return for letting them decrease your cooling remotely at peak times) and the political right threw a national hissyfit.
    - pfdietz 2y ago
      I signed up for this in Illinois and never heard a single peep of complaint about it (nor did I ever notice it when it kicked in.)
  - Workaccount2 2y ago
    If you don't have a smart thermostat, check whoever your utility is for discounts. I got a 50% discount buying it through them.
- cogman10 2y ago
  > Electric cars mostly don't have the circuitry to do this yet Electric cars do have the circuitry to do this. It's built into the CCS protocol which nearly every EV speaks (US and EU). And it's not hard to imagine how this would work. Two big connectors on EVs can ultimately be hooked pretty much directly to the battery. When you plug in, you'll hear a giant "cachunck" which is the relay switching to DC charging. If you want to turn that into a vehicle providing power, the action is exactly the same, "cachunk" the relay which completes the circuit and have the charging station convert that DC power to AC. That's where the actual equipment gap exists. AFAIK, it's basically only ford that's producing a V2H charger. Enphase has one announced since last year, but I've not really seen anything about it since the announcement.
  - shiftpgdn 2y ago
    Tesla has a V2H/V2G (Powershare is the name Tesla uses) available for Cybertruck owners included as part of the vehicle purchase. I am still waiting on mine, despite receiving my Cybertruck almost 6 months ago. I also have the Ford equipment from when I got my Lightning, however finding a competent installer has been impossible. Right now it's collecting spiders in the corner of my garage.
    - cogman10 2y ago
      Do you have anyone that does home battery installations? It should be pretty much the exact same process to install one of these. It may be somewhat new tech, but ultimately it should look identical to battery controller install.
    - mensetmanusman 2y ago
      Don’t forget about airplanes, you can fly in competent installers, some may enjoy the trip :)
    - tnel77 2y ago
      A Lightning and a CyberTruck? Have either touched dirt? :)
- jogjayr 2y ago
  Wouldn't you want to reduce the number of charge/discharge cycles on your EV battery? Using it for household needs outside of an emergency seems wasteful.
  - moooo99 2y ago
    A modern battery far outlives the rest of the vehicle when you look at the charging cycles. So you can afford to use some of it for home electricity storage. AFAIK some cells types easily last 3,000 cycles at >80% capacity. Assume 400km/charge you’d be looking at 1.2mil kilometers of driving just based on the battery. Also, there is a a natural limit to how much you’re using, considering you also want to use your vehicle for driving as well.
  - neallindsay 2y ago
    Not every charge/discharge wears on the battery the same. Staying at 0% or 100% is worse than staying around the middle. Charging and discharging extremely quickly wears more than slow charges/discharges. And high temperatures are bad for battery health in general. Electric car batteries are tuned much more conservatively than phone batteries and are massively over-provisioned because US consumers are nervous about exactly the thing you're talking about. That's not too surprising because to a large degree the car IS the battery, but battery wear is generally very well mitigated (with the exception of the Nissan Leaf).
    - hedora 2y ago
      Early Nissan Leafs. At this point, the newer used ones include battery health management, and should be similar to other used EVs. Note that getting an old one with a dead battery makes even less sense than you'd guess: It'll burn out any replacement battery just as fast, assuming you can actually get one.
  - MostlyStable 2y ago
    If I was able to use my EV as an external battery for my home, I could potentially save ~$100 per month on my power bill, and that would represent <1/2 additional charge cycle per day. I'm pretty sure that would be worth it. This is going to depend on the power rates in ones particular area though.
- jeffbee 2y ago
  I think it's appealing to nerds to believe that a long-tail disaggregated phenomenon like EV V2G is going to save the grid, but the apparent truth is that the grid will be saved by central planning and top-down command and control. We see this in California. We have a million EVs registered in the state, but our grid-scale, CPUC-regulated battery stations are still larger in terms of energy storage, and unlike the EV fleet the availability and responsiveness of battery energy storage stations is assured. Load shedding like that in the article is a vanilla feature of electric grids everywhere. Large consumers get discounted power in exchange for agreeing to disconnect during grid emergencies. Because the number of such customers is small, that feature is easy to regulate and you can ignore the game theoretic shenanigans that would emerge from widespread V2G with millions of individual participants.
  - applied_heat 2y ago
    Tesla will come to the utility and say we can offer you 3000 MW of demand response in any granularity you want for $x/hr. $x is usually not very big since the modus operandi for the bulk electric system in North America has been everyone can use as much power as they want whenever they want, so we have had lots of supply. But a couple of times per year $x could be thousands of dollars per MW per hour, for a few hours. So not worth the effort really. Maybe Tesla will offer the demand response more geographically so distribution utilities can also use it for peak shaving on their substations. But that is pretty brave area to be operating in for a utility, depending on Tesla to avoid overloading transformers or risk a localized black out. There would have to be a serious penalty for bidding in the demand response but then not performing as well. I agree it does seem far fetched at this time. Edit: price signals to consumers is probably a better mechanism
  - szvsw 2y ago
    > appealing to nerds to believe that a long-tail disaggregated phenomenon like EV V2G is going to save the grid, but the apparent truth is that the grid will be saved by central planning and top-down command and control. I think this sentiment applies to a lot of facets of the energy transition/preventing climate collapse - perhaps sadly? A lot of the cooler distributed solutions and demand-side solutions could have been our saviors had we started on them in earnest 10-15 years ago. They should still be pursued as part of a robust and resilient system (everything from re-insulating homes to V2G to cutting out dairy and meat from diets to dispatchable home heating/cooling-appliances etc etc) but the truth is that we are spiraling towards climate collapse and those sorts of solutions are simply put more difficult to implement and maintain, especially because they often involve massive social buy in; at the same time, those solutions don’t tend to address the source energy question in any meaningful way (besides rooftop PV which is not enough even for low energy homes in many climates), so supply-side solutions will always still be needed, and like you said, there are economies of scale in both thermodynamic/physics efficiencies and in management and planning. It would be awesome if everyone stopped eating steak, but the realist in me knows that expecting that to happen at a scale which moves the needle just does not seem realistic. It’s sad to me in that the “distributed” solutions tend to actually address root causes of climate catastrophe - addiction to energy consumption, “capitalism” writ large, being good denizens of the planet, etc etc in one way or another - and would entail a real improvement to how we understand the fabric of society and modern civilization (I’m speaking broadly here of course, but I think it holds water), whereas the centralized solutions feel in some sense like bandaids that obfuscate our collective responsibility and engagement with the issue (besides tax dollars and utility rates going towards the solutions I guess), but at the timescale of the crisis we are dealing with the size of that lever and its effectiveness is kind of unarguable I think. Build big solar and wind farms, lots of batteries, start using cleaner steel and cement manufacturing processes, hope that super deep geothermal or micro-reactors progress, hope that we find a better way to sequester carbon coming from either direct air capture or post-combustion carbon capture. Everything else is just (important) gravy. And I say this as someone mostly focused on the demand side, not supply side! (I’m a building scientist)
- rtkwe 2y ago
  There are a number of industries that also do this where they'll be voluntarily shut off or pulled back during times where the grid nears brownout/blackout because their processes are interruptible with minimal cost which for battery charging stations is pretty true unless they're entire stock is at a very low charge.
- adrianmonk 2y ago
  I wouldn't want to participate during emergencies, though. If a hurricane or a winter storm is coming, I want my car at 100% in case I need to evacuate, drive around to get food, etc. On top of that, who knows when I'll be able to charge the car again. If we rely on cars to help stabilize the grid, it's not ideal that people will opt out just when it's needed the most.
ggm 2y ago
Demand management is fantastic, batteries are just amazing and can sink power, provide power, manage reactive power and frequency and do it in milliseconds.
- gorbypark 2y ago
  Once upon a time (~15 years ago!), I worked at a ski resort in New Zealand that had a fancy new "automated" snowmaking system. When all 200 (give or take) snow guns were running, along with the required water pumps/air compressors, the system could draw megawatts of power. Generally it didn't get below zero very often in the closest city to the resort (Queenstown), but when it did, people would turn on their electric heaters, and demand would go through the roof. The way it was explained to me is that the power company actually sent a signal through the power supply which would trigger our snowmaking system to shut itself off. It was pretty cool to see and also infuriating, because of course you can make much more snow when it's cold. Being a giant nerd I of course asked if this was really happening via some network connection, but I was told they actually modulated the frequency of the entire grid in a very small, but predictable way. Some sort of device sat there and when it picked up the pattern in the frequency changes it would then trigger the shutdown. I've spent a while doing some searches about such a system but couldn't find any information. Anyways, your comment about demand management made me think of this and how it's been possible in one way or another for a long time (albeit not milliseconds!).
  - flakeoil 2y ago
    Are you sure they modulated the frequency of the actual AC power (typically 50 or 60 Hz) and didn't overlay it with a high frequency signal? It's very common with power line communication or power line modems. You modulate a data signal on top.
    - immibis 2y ago
      It's a data signal on top. The system is called "ripple control".
    - ZeroGravitas 2y ago
robocop_legacy 2y ago
“ According to numbers provided by the company, 590 Gogoro battery-swap locations (some of which have more than one swap station) stopped drawing electricity from the grid, lowering local demand by a total six megawatts—enough to power thousands of homes.” From the title I thought the batteries would stabilize the grid by discharging back into it but apparently that capability is not implemented yet. Still interesting that the stations increase demand enough that grid stabilization can occur by simply disabling battery charging.
- cesarb 2y ago
  > Still interesting that the stations increase demand enough that grid stabilization can occur by simply disabling battery charging. That trick is not limited to battery stations. Another thing which is done in some places (at least my country does that), is to have some circuits from substations configured so that they cut power when the frequency drops too low and/or too fast, preventing a generalized blackout at the cost of temporarily losing power to parts of the system (the circuits to be powered down in each step are chosen so that important loads like hospitals do not lose power). In the country-wide blackout last year (https://en.wikipedia.org/wiki/2023_Brazil_blackout https://en.wikipedia.org/wiki/2023_Brazil_blackout), that mechanism stabilized power in the southern part of the country, allowing it to recover quickly (the northern part, where the disturbance originated, unfortunately lost too much transmission and generation, and needed a black start).
- redleader55 2y ago
  I'm bivalent on this topic. On one hand 6MW is very little, compared to 3,200 MW lost power during the earthquake, especially when spread over 580 stations. It's likely the feature to disconnect when frequency drops is designed to protect the station, rather than the grid. In general, this sounds like a feel-good story rather than a something real. That being said, I see this as a huge opportunity to stabilize the grid by having large-ish battery stations discharging their stored power when frequency drops. It's likely this will need to be grid controlled rather than individual and decentralized completely. It's hard (for me) to say what needs to be built first: an automatic way to reduce power draw from the grid by large consumers that are non-essential (eg. industry) or battery stations that can keep the frequency stable in case of brownouts.
EGreg 2y ago
Can't we just charge our electric cars during the DAY, when they are PARKED, and therefore THOSE batteries can be used? Seems like a good use of electricity. Sell it back to the grid during the night so electric cars can charge during the day. Arbitrage the fact that people with panels sell cheaply during the day. It seems to me that anyone could start an electric car parking garage, that 1. receives excess electricity from solar panels around the city and suburbs during the day 2. cheaply charges the electric cars during the day 3. subsidizes powering the homes at night, for those same credits Or probably a better entity to do that would be the public subway system Storing electronic credits instead of energy hehe
- thesis 2y ago
  Sell it back at night when there's already a surplus of electricity? This is exactly why they want EV's charging at night, because there's less demand.
  - jandrese 2y ago
    Typically the sell back time is in the evening, after solar production is done but before people go to bed. Also some in the early morning, albeit to a smaller degree.
  - rtkwe 2y ago
    Depending on the renewables mix the grid settles on, selling some back during the night might make sense. Both solar (obviously) and wind (less obviously, at least to me) decrease during the night so we may find we need to supplement the generation with battery reserves during the night for demand peaks. Nuclear and traditional dammed hydro prefer to be setup to provide extremely consistent power too so there's a gap in the power generation if we completely eliminate fossil fuels. Even if we don't completely eliminate them, peaker plants are extremely expensive to operate because their base costs and ideally low usage means their cost per megawatt is pretty high.
  - EGreg 2y ago
    I there is a surplus of electricity at night, then why have batteries? There seems to be no problem at all with just spot market demand in that case! I thought the issue was that solar panels are generating electricity during the day only. So as someone with solar, you want to sell during the day and buy at night. No? My point is, rather than using batteries to store huge amounts of energy and lose much of it in the process, find efficiencies and use credits instead.
ck2 2y ago
Vaguely related reminder for the USA to buy your large lifepo4 battery backups and solar panels sometime soon in June before the tariffs kick in and double prices next month.
oliwarner 2y ago
Not the story I thought it was going to be. They turned off the chargers, releasing enough capacity for the grid to stabilise. Big woop. This is basic grid planning. Non critical circuits should cut out to stabilise the grid by design. With this sort of praise, I thought they'd returned power to the grid when it slumped.
- amelius 2y ago
  They could have momentarily raised the energy prices and a similar thing would have happened.
  - oliwarner 2y ago
    You can't guarantee industrial customers won't just increase their sales prices with supply. Consider normal EV chargers: They just spike the price for the user. And depending on the market, wholesale prices might be locked in for 24h or more so industry knows its day-to-day costs before it incurs them. Smashing up the prices for tomorrow can generate usage spikes today. Good controls for weather-based supply but not a feature in a national emergency. Above all of this you still need to be able to prioritise physical circuits for healthcare, security, groceries and homes, and be able to cut off others. That said, Gogoro seem to be more about overselling contracts so spiking price probably would make shut down themselves.
jillesvangurp 2y ago
There are multiple terawatt hours per year of committed battery factory investments for the next few years. Current yearly production is only about one twh. With production outstripping demand, we can look forward to prices coming down further. Committed of course does not mean these factories will get built. Quite a few of them will be a combination of redundant and obsolete before they are built. Bloomberg NEF is tracking close to 8 twh worth of battery manufacturing investments for 2025 with demand being estimated at only 1.6 twh. There's a battery bubble happening and this is good news. https://about.bnef.com/blog/china-already-makes-as-many-batteries-as-the-entire-world-wants/ https://about.bnef.com/blog/china-already-makes-as-many-batt... Also, most of these batteries are just sitting there are relatively high charge states (70-80%) not being utilized at all. The point here is that we won't have a battery shortage and a growing amount of potential energy locked up in charged batteries. Keeping these batteries charged is also not that big of a challenge because we're mostly not even discharging them. Cars on average only drive around 14K miles per year. That's only about 3.5 mwh of energy needed per year (at 4 mile/kwh). Or about 59 charging cycles for a 60kwh battery. Batteries also last quite long. So we have this builtup of tens and soon hundreds of twh of battery just sitting there in cars, trucks, grid storage, etc. So with all that happening in the background, swappable batteries are a bit redundant. Also when considering their potential to grid stabilization.
- burnished 2y ago
  Do you have an estimate for their stable life? I don't have an intuition for it and am curious
  - jillesvangurp 2y ago
    15-20 years depending on usage. Mostly, EV manufacturers are very comfortable offering 8 years or 100K miles on their batteries (whichever comes first). Meaning they don't anticipate failures to be a regular thing before that; or long after that. Most batteries should last a lot longer. Most EVs produced ever (i.e. in the last 15 years) are still driving with their original batteries. So that should build some confidence. Some early cars with relatively primitive battery management obviously are getting their batteries replaced. But even then, it's not going to break the bank and extends the lifetime of the vehicle by a decade+. A 4K battery replacement for a 12 year old Nissan Leaf to double its range doesn't sound like a horrible deal, for example. Replacing a 20kwh battery with a 40kwh one for that money is a good deal and extends the life of the vehicle by about 10+ years. Of course it all depends on battery chemistries and battery management. There has been a lot of improvement on both dimensions. Mostly I don't think there will be a lot of surprises on this front as this is a well studied thing.
kkfx 2y ago
Well... the long story short is that a smart-grid works better than a classic one. This example is a very limited kind of smartness, just "stop what you can stop on a strained grid to keep it up", for certain kind of loads in certain countries is a mandatory things: in France IVRE norms for domestic EV charging stations demand a device connected to the utility meter data port (2-wires system) to allow the grid stop (and potentially in the future just regulating the maximum allowed amps) a charge if needed, in some other countries I've read it's common to have connected thermostats the grid can tweak to lower heating/condition when there is too much energy demand. The issue of a smart grid though it's the fact that we need software from various actors, talking together, to regulate a DELICATE and CRITICAL infra. Just imaging if in a nation-wide smart-grid a bug or an attack tell all connected cars/chargers "please charge at maximum amps, we have a renewable production spike, we need load to lower the frequency" while the grid is definitively NOT in such situation or simply the potential cascading effects of some smart-grid demand that can't be immediately applied by all smart-connected customers, creating something we can see also in domestic p.v. with ac-coupled classic string inverters, where the battery inverter demand more energy to the p.v. inverter, while a small cloud reduce the p.v. output, the cloud go, the p.v. suddenly inject much more and the battery inverter flip "reduce, reduce, reduce", another cloud, another spike. IMVHO there is so far no tech safe enough for a PUBLIC smart-grid, we can at maximum have smart-grid-homes meaning local batteries (perhaps small + the EVs in V2H bi-directional direct DC-to-DC mode, since most cars use 400V batteries as most p.v. hybrid inverters on sale, there is no damn reason for a double DC-AC-DC conversion like Tesla PowerWall and others do) and local p.v. keeping a separate home grid, with the national grid directly powering only the main inverter or islandic device. The local system can just keep watching grid frequency shifting regulating the eventual p.v. surplus injection only if the grid frequency is a bit low, and using batteries to a certain SOC level if there is no p.v. and grid frequency is low and tend to trend lower in a certain timeframe. It's not smart, but at least it can't destabilize the grid much, an eventual attacker must been able to poison frequency shifting signals witch typically means having last mile physical access on the grid, something doable locally, but hard to do at a nation-wide or at least wide-enough areas to destabilize the grid.

136 points by belter 2y ago

There's lots of talk about grid-scale batteries to shift cheap electricity from solar panels into the night time. But batteries at the periphery can also help a lot because they can just stop charging (like the example in this article) or even feed energy back into the grid. Electric cars mostly don't have the circuitry to do this yet, but they're becoming a huge resource that will be tappable this way. Most of them are massively over-provisioned for the way that they're used 350 days out of the year.

t_tsonev 2y ago
On-demand charging is very much happening today. All chargers communicate the available charging current with the vehicle and some can adjust it dynamically. As for control, there are proprietary and OSS solutions (shout out to https://evcc.io/en/ https://evcc.io/en/) that allow you to control the charging process based on price, grid load, local PV generation, etc.
- ckdarby 2y ago
  I see the basic version of this already with the Tesla vehicles where if you plug in another appliance on the same breaker the car will decrease its draw to prevent triggering the breaker.
  - cesarb 2y ago
    > where if you plug in another appliance on the same breaker the car will decrease its draw to prevent triggering the breaker. That's alarming. There's no way the car can know that there's another appliance on the same breaker. The only way it can know it should decrease its power draw, is by detecting that the voltage decreased on the circuit, but that voltage decrease will only be noticeable if the wiring is undersized for the load (in fact, that feature is probably designed to protect against overheating undersized wiring on the circuit feeding the car). That circuit is probably severely overloaded, which can be a fire risk.
    - jeffbee 2y ago
      This feature doesn't exist. The Tesla home charger can share current with other Tesla chargers on the same branch. It can't share current with an electric water heater or some other non-Tesla load
      - Retric 2y ago
        I think the OP was just confusing a feature used by someone with a Tesla from a Tesla specific feature. They might be using one of these: https://www.chargedfuture.com/240v-outlet-smart-splitter/ https://www.chargedfuture.com/240v-outlet-smart-splitter/ There’s also smart breaker boxes that again have nothing to do with Tesla specifically. The breaker box will preferentially shed EV charging first when someone would otherwise trip their whole homes’s connection to the grid. It’s not a perfect solution, but sometimes your local utility doesn’t want to upgrade your connection to the grid because their substation is fully provisioned or whatnot.
rthomas6 2y ago
I wish it were standard practice to have some kind of house battery (what Tesla calls "Powerwall") for new construction homes. They could smooth out peak usage in this exact way, in addition to making individual homes more resilient to occasional power outages.
- practicemaths 2y ago
  It might happen! There's a fair bit of active research into repurposing batteries from cars into such a purpose or similar. This both extends the usefulness of the manufactured good (the battery) while also hopefully lowering the upfront costs of new electric cars.
- adgjlsfhk1 2y ago
  IMO this isn't the direction we're going. I'd bet that in 20 years, there will be some form of grid-scale specific battery that is 2-3x cheaper than lithium iron (per joule), but with much worse energy density. Many of the batteries of this type are unsuitable for home installation (because they get more efficient with scale). Some of the potential options for this are things like iron sulfur batteries which require pretty high temps, or some designs for batteries that basically involve physical pumps to pump liquid anodes and cathodes around.
  - szvsw 2y ago
    > some designs for batteries that basically involve physical pumps to pump liquid anodes and cathodes around Yeah in addition to flow batteries there are also grid scale thermal batteries, though these are targeted more towards long duration energy storage: run electricity through a large carbon block in a shipping container form factor to heat it up, then use infrared photovoltaics to convert back to electricity when desired.
    - Teever 2y ago
      I'd be interested in learning more about this carbon block battery that you're describing. I'm also curious how it compares in cost effectiveness to this battery that's based on sand. https://tambaynews.blogspot.com/2022/07/worlds-first-commercial-sand-battery.html https://tambaynews.blogspot.com/2022/07/worlds-first-commerc...
mauvehaus 2y ago
Green Mountain Power does exactly this in Vermont: they have a program that'll install a pair of powerwall batteries at customer homes and charge them off peak to draw on them on peak, particularly to avoid GMP having to buy peak-rate power from their upstream suppliers. In return, they leave the batteries charges when the weather is turning bad and the customer has battery backup. The deal is structured as a 10 year lease, and the total cost is vastly less than that of owning the batteries outright. Their installation allowance is pretty good too; it didn't cover splitting our panel, but it covered everything else. Not affiliated other than being a very happy GMP customer.
- onionisafruit 2y ago
  You say they leave the batteries charged when the power is turning bad. Do you have a benefit of hosting the batteries at other times? For instance if the power goes out when the weather isn’t bad, do you typically have enough charge to make it through the outage? I’m also curious if your neighbors benefit from your battery during outages.
  - mauvehaus 2y ago
    De jure, I think they're pretty free to do with them what they want. De facto they leave the batteries pretty fully charged most of the time. AIUI, they'd have to have a disconnect somewhere upstream of us to let us back feed the grid during an outage, otherwise they couldn't safely work on the lines. And they'd need a way to enable and disable back feeding remotely[0] to allow them to work on anything between that hypothetical disconnect and us. At the moment, none of that exists, so only we benefit from the powerwalls. It's also 34kwh in the pair of batteries. That wouldn't add up to too many household-days if you started adding households. You'd have to do some fancy switching to not overwhelm the relatively few powerwalls in an outage. For context, based on our usage, we're at about three days of backup just for us [1]. It doesn't take much imagination to come up with a scenario where that happens where we are. We are the very last pole. [0] Which in turn requires connectivity. The cell network here is sparse, to put it mildly. We just got fiber, but that's hanging on the same poles as the power. The fail-safe mode for no grid and no connectivity is to not backfeed, but at that point, you're back where you are today. [1] It's the fridge, mostly.
pfdietz 2y ago
Even lower hanging fruit would be increasing the dispatchability of demand in homes. Simply allowing heating and cooling to be dispatched would be very helpful. In the past this was done with bespoke add-ons to furnaces and AC compressors, but now it's done with smart thermostats.
- smileysteve 2y ago
  Dispatched versus random dither are similar; For most smart thermostats, one of the lesser known quality improvements is the 5 minute + dither time for startup. This is designed for compressor health - but prevents repeat cascading brownouts - where programmable thermostats or manual thermostats would have either a strict 5 minute wait time or none at all. Other features like time of use, humidity correction, and fan circulation also drastically reduce energy usage.
  - hedora 2y ago
    Our thermostat seems to apply the delay even when you manually turn it on. It drives me nuts. (After a power failure or during scheduled transitions make sense; after I push the button: not so much.)
- immibis 2y ago
  ISTR they did this somewhere (getting a discount on power in return for letting them decrease your cooling remotely at peak times) and the political right threw a national hissyfit.
  - pfdietz 2y ago
    I signed up for this in Illinois and never heard a single peep of complaint about it (nor did I ever notice it when it kicked in.)
- Workaccount2 2y ago
  If you don't have a smart thermostat, check whoever your utility is for discounts. I got a 50% discount buying it through them.
cogman10 2y ago
> Electric cars mostly don't have the circuitry to do this yet Electric cars do have the circuitry to do this. It's built into the CCS protocol which nearly every EV speaks (US and EU). And it's not hard to imagine how this would work. Two big connectors on EVs can ultimately be hooked pretty much directly to the battery. When you plug in, you'll hear a giant "cachunck" which is the relay switching to DC charging. If you want to turn that into a vehicle providing power, the action is exactly the same, "cachunk" the relay which completes the circuit and have the charging station convert that DC power to AC. That's where the actual equipment gap exists. AFAIK, it's basically only ford that's producing a V2H charger. Enphase has one announced since last year, but I've not really seen anything about it since the announcement.
- shiftpgdn 2y ago
  Tesla has a V2H/V2G (Powershare is the name Tesla uses) available for Cybertruck owners included as part of the vehicle purchase. I am still waiting on mine, despite receiving my Cybertruck almost 6 months ago. I also have the Ford equipment from when I got my Lightning, however finding a competent installer has been impossible. Right now it's collecting spiders in the corner of my garage.
  - cogman10 2y ago
    Do you have anyone that does home battery installations? It should be pretty much the exact same process to install one of these. It may be somewhat new tech, but ultimately it should look identical to battery controller install.
  - mensetmanusman 2y ago
    Don’t forget about airplanes, you can fly in competent installers, some may enjoy the trip :)
  - tnel77 2y ago
    A Lightning and a CyberTruck? Have either touched dirt? :)
jogjayr 2y ago
Wouldn't you want to reduce the number of charge/discharge cycles on your EV battery? Using it for household needs outside of an emergency seems wasteful.
- moooo99 2y ago
  A modern battery far outlives the rest of the vehicle when you look at the charging cycles. So you can afford to use some of it for home electricity storage. AFAIK some cells types easily last 3,000 cycles at >80% capacity. Assume 400km/charge you’d be looking at 1.2mil kilometers of driving just based on the battery. Also, there is a a natural limit to how much you’re using, considering you also want to use your vehicle for driving as well.
- neallindsay 2y ago
  Not every charge/discharge wears on the battery the same. Staying at 0% or 100% is worse than staying around the middle. Charging and discharging extremely quickly wears more than slow charges/discharges. And high temperatures are bad for battery health in general. Electric car batteries are tuned much more conservatively than phone batteries and are massively over-provisioned because US consumers are nervous about exactly the thing you're talking about. That's not too surprising because to a large degree the car IS the battery, but battery wear is generally very well mitigated (with the exception of the Nissan Leaf).
  - hedora 2y ago
    Early Nissan Leafs. At this point, the newer used ones include battery health management, and should be similar to other used EVs. Note that getting an old one with a dead battery makes even less sense than you'd guess: It'll burn out any replacement battery just as fast, assuming you can actually get one.
- MostlyStable 2y ago
  If I was able to use my EV as an external battery for my home, I could potentially save ~$100 per month on my power bill, and that would represent <1/2 additional charge cycle per day. I'm pretty sure that would be worth it. This is going to depend on the power rates in ones particular area though.
jeffbee 2y ago
I think it's appealing to nerds to believe that a long-tail disaggregated phenomenon like EV V2G is going to save the grid, but the apparent truth is that the grid will be saved by central planning and top-down command and control. We see this in California. We have a million EVs registered in the state, but our grid-scale, CPUC-regulated battery stations are still larger in terms of energy storage, and unlike the EV fleet the availability and responsiveness of battery energy storage stations is assured. Load shedding like that in the article is a vanilla feature of electric grids everywhere. Large consumers get discounted power in exchange for agreeing to disconnect during grid emergencies. Because the number of such customers is small, that feature is easy to regulate and you can ignore the game theoretic shenanigans that would emerge from widespread V2G with millions of individual participants.
- applied_heat 2y ago
  Tesla will come to the utility and say we can offer you 3000 MW of demand response in any granularity you want for $x/hr. $x is usually not very big since the modus operandi for the bulk electric system in North America has been everyone can use as much power as they want whenever they want, so we have had lots of supply. But a couple of times per year $x could be thousands of dollars per MW per hour, for a few hours. So not worth the effort really. Maybe Tesla will offer the demand response more geographically so distribution utilities can also use it for peak shaving on their substations. But that is pretty brave area to be operating in for a utility, depending on Tesla to avoid overloading transformers or risk a localized black out. There would have to be a serious penalty for bidding in the demand response but then not performing as well. I agree it does seem far fetched at this time. Edit: price signals to consumers is probably a better mechanism
- szvsw 2y ago
  > appealing to nerds to believe that a long-tail disaggregated phenomenon like EV V2G is going to save the grid, but the apparent truth is that the grid will be saved by central planning and top-down command and control. I think this sentiment applies to a lot of facets of the energy transition/preventing climate collapse - perhaps sadly? A lot of the cooler distributed solutions and demand-side solutions could have been our saviors had we started on them in earnest 10-15 years ago. They should still be pursued as part of a robust and resilient system (everything from re-insulating homes to V2G to cutting out dairy and meat from diets to dispatchable home heating/cooling-appliances etc etc) but the truth is that we are spiraling towards climate collapse and those sorts of solutions are simply put more difficult to implement and maintain, especially because they often involve massive social buy in; at the same time, those solutions don’t tend to address the source energy question in any meaningful way (besides rooftop PV which is not enough even for low energy homes in many climates), so supply-side solutions will always still be needed, and like you said, there are economies of scale in both thermodynamic/physics efficiencies and in management and planning. It would be awesome if everyone stopped eating steak, but the realist in me knows that expecting that to happen at a scale which moves the needle just does not seem realistic. It’s sad to me in that the “distributed” solutions tend to actually address root causes of climate catastrophe - addiction to energy consumption, “capitalism” writ large, being good denizens of the planet, etc etc in one way or another - and would entail a real improvement to how we understand the fabric of society and modern civilization (I’m speaking broadly here of course, but I think it holds water), whereas the centralized solutions feel in some sense like bandaids that obfuscate our collective responsibility and engagement with the issue (besides tax dollars and utility rates going towards the solutions I guess), but at the timescale of the crisis we are dealing with the size of that lever and its effectiveness is kind of unarguable I think. Build big solar and wind farms, lots of batteries, start using cleaner steel and cement manufacturing processes, hope that super deep geothermal or micro-reactors progress, hope that we find a better way to sequester carbon coming from either direct air capture or post-combustion carbon capture. Everything else is just (important) gravy. And I say this as someone mostly focused on the demand side, not supply side! (I’m a building scientist)
rtkwe 2y ago
There are a number of industries that also do this where they'll be voluntarily shut off or pulled back during times where the grid nears brownout/blackout because their processes are interruptible with minimal cost which for battery charging stations is pretty true unless they're entire stock is at a very low charge.
adrianmonk 2y ago
I wouldn't want to participate during emergencies, though. If a hurricane or a winter storm is coming, I want my car at 100% in case I need to evacuate, drive around to get food, etc. On top of that, who knows when I'll be able to charge the car again. If we rely on cars to help stabilize the grid, it's not ideal that people will opt out just when it's needed the most.

ggm 2y ago

Demand management is fantastic, batteries are just amazing and can sink power, provide power, manage reactive power and frequency and do it in milliseconds.

gorbypark 2y ago
Once upon a time (~15 years ago!), I worked at a ski resort in New Zealand that had a fancy new "automated" snowmaking system. When all 200 (give or take) snow guns were running, along with the required water pumps/air compressors, the system could draw megawatts of power. Generally it didn't get below zero very often in the closest city to the resort (Queenstown), but when it did, people would turn on their electric heaters, and demand would go through the roof. The way it was explained to me is that the power company actually sent a signal through the power supply which would trigger our snowmaking system to shut itself off. It was pretty cool to see and also infuriating, because of course you can make much more snow when it's cold. Being a giant nerd I of course asked if this was really happening via some network connection, but I was told they actually modulated the frequency of the entire grid in a very small, but predictable way. Some sort of device sat there and when it picked up the pattern in the frequency changes it would then trigger the shutdown. I've spent a while doing some searches about such a system but couldn't find any information. Anyways, your comment about demand management made me think of this and how it's been possible in one way or another for a long time (albeit not milliseconds!).
- flakeoil 2y ago
  Are you sure they modulated the frequency of the actual AC power (typically 50 or 60 Hz) and didn't overlay it with a high frequency signal? It's very common with power line communication or power line modems. You modulate a data signal on top.
  - immibis 2y ago
    It's a data signal on top. The system is called "ripple control".
  - ZeroGravitas 2y ago

robocop_legacy 2y ago

“ According to numbers provided by the company, 590 Gogoro battery-swap locations (some of which have more than one swap station) stopped drawing electricity from the grid, lowering local demand by a total six megawatts—enough to power thousands of homes.” From the title I thought the batteries would stabilize the grid by discharging back into it but apparently that capability is not implemented yet. Still interesting that the stations increase demand enough that grid stabilization can occur by simply disabling battery charging.

cesarb 2y ago
> Still interesting that the stations increase demand enough that grid stabilization can occur by simply disabling battery charging. That trick is not limited to battery stations. Another thing which is done in some places (at least my country does that), is to have some circuits from substations configured so that they cut power when the frequency drops too low and/or too fast, preventing a generalized blackout at the cost of temporarily losing power to parts of the system (the circuits to be powered down in each step are chosen so that important loads like hospitals do not lose power). In the country-wide blackout last year (https://en.wikipedia.org/wiki/2023_Brazil_blackout https://en.wikipedia.org/wiki/2023_Brazil_blackout), that mechanism stabilized power in the southern part of the country, allowing it to recover quickly (the northern part, where the disturbance originated, unfortunately lost too much transmission and generation, and needed a black start).
redleader55 2y ago
I'm bivalent on this topic. On one hand 6MW is very little, compared to 3,200 MW lost power during the earthquake, especially when spread over 580 stations. It's likely the feature to disconnect when frequency drops is designed to protect the station, rather than the grid. In general, this sounds like a feel-good story rather than a something real. That being said, I see this as a huge opportunity to stabilize the grid by having large-ish battery stations discharging their stored power when frequency drops. It's likely this will need to be grid controlled rather than individual and decentralized completely. It's hard (for me) to say what needs to be built first: an automatic way to reduce power draw from the grid by large consumers that are non-essential (eg. industry) or battery stations that can keep the frequency stable in case of brownouts.

EGreg 2y ago

Can't we just charge our electric cars during the DAY, when they are PARKED, and therefore THOSE batteries can be used? Seems like a good use of electricity. Sell it back to the grid during the night so electric cars can charge during the day. Arbitrage the fact that people with panels sell cheaply during the day. It seems to me that anyone could start an electric car parking garage, that 1. receives excess electricity from solar panels around the city and suburbs during the day 2. cheaply charges the electric cars during the day 3. subsidizes powering the homes at night, for those same credits Or probably a better entity to do that would be the public subway system Storing electronic credits instead of energy hehe

thesis 2y ago
Sell it back at night when there's already a surplus of electricity? This is exactly why they want EV's charging at night, because there's less demand.
- jandrese 2y ago
  Typically the sell back time is in the evening, after solar production is done but before people go to bed. Also some in the early morning, albeit to a smaller degree.
- rtkwe 2y ago
  Depending on the renewables mix the grid settles on, selling some back during the night might make sense. Both solar (obviously) and wind (less obviously, at least to me) decrease during the night so we may find we need to supplement the generation with battery reserves during the night for demand peaks. Nuclear and traditional dammed hydro prefer to be setup to provide extremely consistent power too so there's a gap in the power generation if we completely eliminate fossil fuels. Even if we don't completely eliminate them, peaker plants are extremely expensive to operate because their base costs and ideally low usage means their cost per megawatt is pretty high.
- EGreg 2y ago
  I there is a surplus of electricity at night, then why have batteries? There seems to be no problem at all with just spot market demand in that case! I thought the issue was that solar panels are generating electricity during the day only. So as someone with solar, you want to sell during the day and buy at night. No? My point is, rather than using batteries to store huge amounts of energy and lose much of it in the process, find efficiencies and use credits instead.

ck2 2y ago

Vaguely related reminder for the USA to buy your large lifepo4 battery backups and solar panels sometime soon in June before the tariffs kick in and double prices next month.

oliwarner 2y ago

Not the story I thought it was going to be. They turned off the chargers, releasing enough capacity for the grid to stabilise. Big woop. This is basic grid planning. Non critical circuits should cut out to stabilise the grid by design. With this sort of praise, I thought they'd returned power to the grid when it slumped.

amelius 2y ago
They could have momentarily raised the energy prices and a similar thing would have happened.
- oliwarner 2y ago
  You can't guarantee industrial customers won't just increase their sales prices with supply. Consider normal EV chargers: They just spike the price for the user. And depending on the market, wholesale prices might be locked in for 24h or more so industry knows its day-to-day costs before it incurs them. Smashing up the prices for tomorrow can generate usage spikes today. Good controls for weather-based supply but not a feature in a national emergency. Above all of this you still need to be able to prioritise physical circuits for healthcare, security, groceries and homes, and be able to cut off others. That said, Gogoro seem to be more about overselling contracts so spiking price probably would make shut down themselves.

jillesvangurp 2y ago

There are multiple terawatt hours per year of committed battery factory investments for the next few years. Current yearly production is only about one twh. With production outstripping demand, we can look forward to prices coming down further. Committed of course does not mean these factories will get built. Quite a few of them will be a combination of redundant and obsolete before they are built. Bloomberg NEF is tracking close to 8 twh worth of battery manufacturing investments for 2025 with demand being estimated at only 1.6 twh. There's a battery bubble happening and this is good news. https://about.bnef.com/blog/china-already-makes-as-many-batteries-as-the-entire-world-wants/ https://about.bnef.com/blog/china-already-makes-as-many-batt... Also, most of these batteries are just sitting there are relatively high charge states (70-80%) not being utilized at all. The point here is that we won't have a battery shortage and a growing amount of potential energy locked up in charged batteries. Keeping these batteries charged is also not that big of a challenge because we're mostly not even discharging them. Cars on average only drive around 14K miles per year. That's only about 3.5 mwh of energy needed per year (at 4 mile/kwh). Or about 59 charging cycles for a 60kwh battery. Batteries also last quite long. So we have this builtup of tens and soon hundreds of twh of battery just sitting there in cars, trucks, grid storage, etc. So with all that happening in the background, swappable batteries are a bit redundant. Also when considering their potential to grid stabilization.

burnished 2y ago
Do you have an estimate for their stable life? I don't have an intuition for it and am curious
- jillesvangurp 2y ago
  15-20 years depending on usage. Mostly, EV manufacturers are very comfortable offering 8 years or 100K miles on their batteries (whichever comes first). Meaning they don't anticipate failures to be a regular thing before that; or long after that. Most batteries should last a lot longer. Most EVs produced ever (i.e. in the last 15 years) are still driving with their original batteries. So that should build some confidence. Some early cars with relatively primitive battery management obviously are getting their batteries replaced. But even then, it's not going to break the bank and extends the lifetime of the vehicle by a decade+. A 4K battery replacement for a 12 year old Nissan Leaf to double its range doesn't sound like a horrible deal, for example. Replacing a 20kwh battery with a 40kwh one for that money is a good deal and extends the life of the vehicle by about 10+ years. Of course it all depends on battery chemistries and battery management. There has been a lot of improvement on both dimensions. Mostly I don't think there will be a lot of surprises on this front as this is a well studied thing.

kkfx 2y ago

Well... the long story short is that a smart-grid works better than a classic one. This example is a very limited kind of smartness, just "stop what you can stop on a strained grid to keep it up", for certain kind of loads in certain countries is a mandatory things: in France IVRE norms for domestic EV charging stations demand a device connected to the utility meter data port (2-wires system) to allow the grid stop (and potentially in the future just regulating the maximum allowed amps) a charge if needed, in some other countries I've read it's common to have connected thermostats the grid can tweak to lower heating/condition when there is too much energy demand. The issue of a smart grid though it's the fact that we need software from various actors, talking together, to regulate a DELICATE and CRITICAL infra. Just imaging if in a nation-wide smart-grid a bug or an attack tell all connected cars/chargers "please charge at maximum amps, we have a renewable production spike, we need load to lower the frequency" while the grid is definitively NOT in such situation or simply the potential cascading effects of some smart-grid demand that can't be immediately applied by all smart-connected customers, creating something we can see also in domestic p.v. with ac-coupled classic string inverters, where the battery inverter demand more energy to the p.v. inverter, while a small cloud reduce the p.v. output, the cloud go, the p.v. suddenly inject much more and the battery inverter flip "reduce, reduce, reduce", another cloud, another spike. IMVHO there is so far no tech safe enough for a PUBLIC smart-grid, we can at maximum have smart-grid-homes meaning local batteries (perhaps small + the EVs in V2H bi-directional direct DC-to-DC mode, since most cars use 400V batteries as most p.v. hybrid inverters on sale, there is no damn reason for a double DC-AC-DC conversion like Tesla PowerWall and others do) and local p.v. keeping a separate home grid, with the national grid directly powering only the main inverter or islandic device. The local system can just keep watching grid frequency shifting regulating the eventual p.v. surplus injection only if the grid frequency is a bit low, and using batteries to a certain SOC level if there is no p.v. and grid frequency is low and tend to trend lower in a certain timeframe. It's not smart, but at least it can't destabilize the grid much, an eventual attacker must been able to poison frequency shifting signals witch typically means having last mile physical access on the grid, something doable locally, but hard to do at a nation-wide or at least wide-enough areas to destabilize the grid.