I think flash charging infra math is:

1500 kWh battery storage + 600kW grid draw + 30kW solar canopy (if weather allows).

@10m per car across 2 cables = ~36 cars over 3 hour rush hour throughput (comparable to 2 gas pump) = need ~4000 kWh, 1500 kWh from battery 1800 kWh from grid = 3300 kWh. This worst case all cars 0-97% charge, realistically mixture so 3300 kWh should cover typical peak scenarios. Then midday lull for grid to refill batteries for evening rush, after again overnight charge from grid. Basically 1x2cable station can service 100-150 cars/day comparable to high-density gas pump.

In terms of physical size, battery storage smaller than gas in terms of physical infra = doesn't need to be underground (assuming long term blade safety ensured). Gas needs storage for multiple days / week so need to scale underground tank accordingly. 1500kWh scaled for rush hour = battery storage (recycled) realistically ~30 recycled blade1s slapped into racks, a couple parking spaces worth, and can be stacked vertically. It's much more space efficient (and cost efficient) than gas.

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ZeroGravitas 2 days ago | parent | next [-]

I don't think it's that big a deal.

Even older supercharger sites in crumbling post-collapse USA are 1MW (4x 250KW stalls).

I think Tesla has an off grid(!) supercharger site in California with 168x 500kW peak v4 chargers.

It seems pretty doable to just spread the chargers around to meet the same throughput without causing any hot spots on the grid. The cars already have internet connected navigation systems that can react to how busy a site is and direct you to the next one.

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maxglute 2 days ago | parent | next [-]

Big deal for ubiquitous charge and moving away from charge hub model. Stop by any local convenience store and getting topped up in 10 min, no need to even consider detour time, i.e. BYD parterning up with KFC china to add flash charge - KFCs everywhere in PRC. The bigger deal is infra play, battery buffer mitigates grid hotspots (supercharger sites), so drop station in box in more places with less regulatory drama / capex in grid rework. Combining short charge time + ubiquitous/dropin charger combo that makes it work. Removes friction for drivers and much more economical for builders, can replace 60 spot supercharger site with 10 flash chargers. Instead of building out a charging hub, slap a few chargers in some existing retail lots, i.e. charge where you fastfood with minimal of permitting and construction - the hardware are cabinets on concrete ground pad- it's closer to modular appliance like industrial hvac than infra. Potential for proliferation very fast. IMO it's intermodal container moment for charging.

	▲	close04 2 days ago \| parent [-]
		> The bigger deal is infra play, battery buffer mitigates grid hotspots That's exactly where I flagged the challenge earlier to which you replied that the math is easy. >> 1500 kWh battery storage + 600kW grid draw + 30kW solar canopy Just for 2 stalls you need to provide 2MW peak power (e.g. 1MW from the grid and 1MW from the battery), and you need probably at least 2MWh local storage to make sure you can always buffer the load. Add the large solar installation to "trickle charge" that battery. Every KFC needs upgrade works for the grid, the battery, and the solar panels. That's technically possible but financially not too attractive. Transformers are in short supply, construction work to upgrade every one of the lines isn't fast or cheap, and the production capacity isn't there yet to feed to the upgraded grid. That's why I said decades. China might pull it off because they can steamroll objections and focus on individual topics to push them according to the plan. Can many other countries afford this?

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close04 2 days ago | parent | prev [-]

> I don't think it's that big a deal.

Nothing ever is when you just have to type about it.

> 1MW (4x 250KW stalls)

Flash charging is 1MW per stall. You can lower the speed but then you're not flash charging.

The challenge isn't whether you can build a 1MW charger, BYD literally did it already [0] and is planning to build 4000 of them across China. The big deal is to do what OP proposed, to convert many small convenience store parking lots to flash charging type sites. The technology for a 1MW charger is there, scaling this to "many small parking lots" [1] is damn hard. It needs rebuilding the power grid for the increased capacity, and having enough local storage. Neither is cheap and fast to get.

[0] https://www.byd.com/mea/news-list/byd-unveils-super-e-platfo...

[1] https://news.ycombinator.com/item?id=47932032

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close04 2 days ago | parent | prev [-]

>> convert many small lots, i.e. convenience stores into recharge stations like gas stations

> 1500 kWh battery storage + 600kW grid draw + 30kW solar canopy

The math doesn't work for converting "many small lots" unless you get creative about what "many" and "small" mean. Every one of those lots needs the 1500 kWh battery storage + 600kW grid draw + 30kW solar installation. It's not a problem of whether the technology exists, but scaling it in an economically feasible manner.

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maxglute 2 days ago | parent [-]

It's moving power requirement from industrial scale to commercial scale, not even large commercial. See BYD partnering with 10000s of PRC KFCs, if the grid can support KFCs it can support flash charge, which makes it more or less ubiquitous anywhere with reliable grid.

The modularization + battery is what makes variable scaling feasible, do not even need full 1500 kWh + 600kW grid power depending on throughput, that's based on max utilization parity with gas pumps, most systems can be smaller. System is also inherently variable mix match grid draw and battery % according to need. i.e. 500kHw battery storage and 300kWh draw for low utility areas. More battery for high utility area which going to have good grid anyway (at least in PRC). The scaling is easy because as mentioned in another comment, the system is almost drop in, commercial HVAC / applicate installation.

AND because it's functionally drop in, low footprint, there is no minimal # of piles, you can spread 1-2 piles in any lot with a couple spots to spare because you don't have high fixed capex of digging a big ass underground oil tank or permitting / earthworks for charging hub with many piles. The system scales to smallest possible increment, ~1-2 parking spots for pile charger + recycled battery. Everything on paper makes this stack MORE economical and easier to proliferate in more spatial configurations than gas / hub charging infra assuming there is grid. i.e. this won't work in off grid stations.

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close04 2 days ago | parent [-]

I'm sorry to say it but a lot of your assumptions are not accurate. Nothing is impossible but it's a lot harder than your assumptions make it look.

> if the grid can support KFCs it can support flash charge

A large KFC probably peaks at 200kW. Stoves, HVAC, lighting. A single flash charging stall could power 10 average KFCs. I hope this puts things in context.

> See BYD partnering with 10000s of PRC KFCs

BYD said they'll build 4000 charging stations [0]. China can pull it off because they can afford to "stick to the plan" no matter what and because they're able to manufacture the necessary grid components to keep up [1]. Can many other countries?

> do not even need full 1500 kWh + 600kW grid power depending on throughput

You keep doing the math that ignores one term: per stall. You either have the capacity to flash charge at every stall, or you don't and you have to find excuses for your customer and move the goalposts in this conversation. If you want to guarantee that capacity then you need no less than 1MW/stall. How you supply it doesn't matter but grid+battery have to supply it. No matter how you mix and match and balance, you'll need to install one and upgrade the other.

> the system is almost drop in, commercial HVAC / applicate installation.

Except you don't replace an existing installation, you add something that needs 10+ times the electrical capacity of everything else put together. That increase needs to be accounted for somewhere.

> you can spread 1-2 piles in any lot with a couple spots to spare because you don't have high fixed capex of digging a big ass underground oil tank or permitting / earthworks for charging hub with many piles.

You literally have to do all that work but for the grid, transformers, panels. KFCs aren't built with 2MW overhead just in case.

[0] https://www.byd.com/mea/news-list/byd-unveils-super-e-platfo...

[1] https://news.ycombinator.com/item?id=47604887

	▲	maxglute 7 hours ago \| parent [-]
		You're only assuming max utility installation, yes would have to do grid upgrade to sustain continuous utilization in those scenarios. I highlight 1500+600+ all flash/blade2 10m throughput to show system is parity with most heavy utility gas model. But for many installations, 100-200kwh grid + 1500kwh battery peak shaving enough to decouple from grid / not require immediate grid upgrade. 1500kwh storage + whatever commercial local grid plugin (i.e. 100-200kW drip) with battery peak will suffice in many current market scenarios. Have to factor in actually blade2 adoption timeline and charging habit etc, i.e. 1500kwh+100kwh/200kwh = 4000-6000kwh which is enough for 40-100 cars (not all going from 0-100, avg ~50-60kwh topup charge). For most markets this is gas pump speed for blade2s + flash, or ubiquitous charging without major grid overhaul for legacy. Will take years for blade2 saturation so that is years of infra/leadtime buffer, or alternatively just slap more piles + battery to simply reduce grid contribution, but under CURRENT market conditions, this is drop in installation for immediate value, with multi year lead time to upgrade grid if required. THE MARKET REALITY for years is 2x1MW/stall all the time is going to be edge case, and something software (i.e. PRC already have energy rate arbitrage queueing) will have to address as they become more common / battery buffer cannot keep up with. Until then the important infra consideration is installation is 100-200kwh spread over multiple likely preexisting commercial level transformers (which is months leadtime hack vs years utility for less infra competent regions). Napkin math is ~10 (i.e. 20 hoses) of these will match typical western neighbourhood gas station throughput. This not considering markets where home/residential BESS will shift even more charging to night curve, i.e. we should expect less 0-97 behavior and more topup demand. Yes execution difference is PRC transformer / utility lead times is in months to hook up the full 600kWh+, but for everyone else the system allows them to hedge with battery in lieu of immediate utility scale grid upgrades. The battery buffer realistically defers major upgrades to enable installation now, because even if upgrade required, it would be commercial vs utility scale in terms of paperwork and leadtime. When I bring up KFC, I'm not saying they're using KFC power, I'm emphasising system works on commercial level power hookup not utility level, i.e. commercial power during night/lulls + battery peak shaving + small spatial requirements + drop in WITHOUT upgrade opens up much more micro charging sites, instead of a charge hub with utility hookup, can spread piles over dozen restaurants with local grid without major upgrades for years until blade2 or more hungry packs reaches saturation. KFC doesn't need 2MW to spare, the immediate commercial grid just needs 100-200kwh to spare, i.e. enough spare capacity for another walk in freezer, most commercial sites have that overhead and battery peak shaves / recharges / balance typically synergize with with business activity.