Hacker News Reader

Comment by spywaregorilla | Hacker News Reader

Using electric vehicles as batteries seems like a good way to run extra cycles through your car and need a replacement battery. It would seem to be a useful emergency feature, but not a steady state part of the grid.

View on HN

I'm very skeptical it will ever take off: the wear and tear of your high performance, high density, mobility optimized battery that has a unique vendor that tightly controls the spare parts market for maximum profit would be much more expensive then intra-day price differentials of the energy market.

On the long run you are effectively competing against industrial scale storage operations that use exceptionally large infrastructure, optimized for low cost, lower density chemistries (Sodium instead of Lithium), with charge profiles optimized for very high number of daily cycles, or even multiples per day etc.

So even if grid battery storage becomes the main thing stabilizing the renewable grid, it still makes little sense to use your car for that, except in emergencies, a "virtual energy supplier", you are paid for the availability, not the actual delivery.

It can be a simple free market thing: you earn enough from renting your battery to make it worth the extra cycles. Or if the grid operator can build enough cheaper energy storage themselves, then they won't use your v2l capability.

If there's going to be an increased demand for grid-stabilizing storage, it will price the supply accordingly.

If its a simple free market thing, then you won't use your car battery to supply the grid, because the economics wouldn't work out. So the issue remains.

In the Tesla virtual grid test in California currently they're paying 50 cents per kWh. That causes 2 cents worth of degradation to the battery, but only if that's a 100% to 0% to 100% cycle. If instead it's a 80% to 20% to 80% cycle, it's about 0.2 cents worth of degradation.

I think OP made the point that in the free market the companies could pay you a certain fee per charge used or something, so that you get remunerated for your battery being used.

Yes and the value you provide to the grid is less than the cost of cycling your car battery. So it wouldn't work out.

You could also pay people to turn magnet wheels for power at night. But it wouldn't work out.

You've provided very little support for your position. To be fair, I don't think you are claiming that the idea of using batteries in such a way doesn't make sense as we already know that there are successful deployments of batteries doing exactly this (I mean, you could argue that those deployments aren't actually successful and that they aren't properly taking into account the replacement costs of their batteries, but I don't think there's evidence of that). So then the argument comes down to, why would a power supplier pay individual owners of relatively small batteries to do this when they could just deploy batteries at scale. That then is the more interesting consideration and I don't think it's actually clear that the economics don't work out. Private batteries have some benefits to power companies, for example the infrastructure to support them is almost free (as it's otherwise already required), there's no long-term risk of building out too much (i mean, there is, but the power company doesn't have that risk), etc. All in, it could be that the power company is better served by building out batteries themselves, but that their own battery storage ends up always under-provisioned and that it is economically beneficial to everyone that they then use private distributed battery storage to shore that up.

This afternoon, in Kansas, the electric company paid us to run our farm off a diesel generator for 3 hours to reduce the load on the grid.

Even though fuel price is high, and a 80kw generator isn't nearly as efficient as the utility company's generators, they still pay enough to make it easily worth it. Including the cost of the generator, which we need anyways.

The electric company could pay enough to more than cover the battery cycle expense.

Plus, if Li-ion are at all similar in this to lead-acid, a deep cycle is many many times more destructive than a shallow cycle.

Really depends on depth of discharge.

A 5x time 20% drain to help the grid isn't anywhere as harmful as a full 100% discharge in emergency mode trying to get to a charging station and not get stranded.

Besides, we could have methods of compensating people for helping stabilize the grid. And of course no one is forcing you to participate in this scheme anyway.

> Besides, we could have methods of compensating people for helping stabilize the grid. And of course no one is forcing you to participate in this scheme anyway.

We don't have profitable methods, so it's moot.

Do we even know the battery pack replacement cost ? Has any customer paid for it yet or are we still in the honeymoon phase where the manufacturer covers the cost to lure more customers?

Of course the prices are available, for every car model. It's not US healthcare :D

There's also long-term battery health data available now from Teslas and Leaf. Tesla batteries degrade 1%-2% per year on average.

Here are UK battery prices (this is the priciest component of an EV, the upside is that motors and transmission may last car's lifetime):

    Audi e-tron - £6,194.40 (71.2)
    Audi e-tron GT - £8,125.80 (93.4)
    Audi e-tron Sportback - £6,177 (71)
    Audi Q4 e-tron - £4,524 (55)
    BMW i3 - £3,297.30 (37.9)
    BMW i4 - £7,020.90 (80.7)
    BMW iX3 - £6,423.21 (73.83)
    BMW iX - £6,177 (71)
    Citroën ë-Berlingo - £4,350 (50)
    Citroën ë-C4 - £4,350 (50)
    Citroën ë-Spacetourer - £4,350 (50)
    Cupra e-Born - £5,394 (62)
    DS 3 Crossback E-Tense - £4,350 (50)
    Fiat 500e - £2,088 (24)
    Ford Mustang Mach-E - £6,585.90 (75.7)
    Honda e - £3,088.50 (35.5)
    Hyundai Ioniq 5 - £5,063.40 (58.2)
    Hyundai Ioniq Electric - £3,332.10 (38.3)
    Hyundai Kona Electric - £3,410.40 (39.2)
    Jaguar I-Pace - £7,830 (90)
    Kia EV6 - £6,733.80 (77.4)
    Kia e-Niro - £5,568 (64)
    Kia Soul EV - £5,568 (64)
    Lexus UX300e - £4,724.10 (54.3)
    Mazda MX-30 - £3,088.50 (35.5)
    Mercedes-Benz EQA - £5,785.50 (66.5)
    Mercedes-Benz EQB - £5,785.50 (66.5)
    Mercedes-Benz EQC - £6,960 (80)
    Mercedes-Benz EQE - £7,830 (90)
    Mercedes-Benz EQS - £9,378.60 (107.8)
    Mercedes-Benz EQV - £8,700 (100 kWh)
    MG5 EV - £5,315.70 (61.1 kWh)
    MG ZS EV - £4,445.70 (51.1)
    MINI Electric - £2,836.20 (32.6)
    Nissan E-NV200 COMBI - £3,480 (40)
    Nissan Leaf - £3,393 (39)
    Peugeot e-208 - £4,350 (50)
    Peugeot e-2008 - £4,350 (50)
    Peugeot e-Rifter - £4,350 (50)
    Peugeot e-Traveller - £4,350 (50)
    Polestar 2 - £6,003 (69)
    Porsche Taycan - £6,890.40 (79.2)
    Renault Zoe - £4,524 (52)
    Škoda ENYAQ iV - £6,699 (77)
    Škoda ENYAQ Coupe - £6,699 (77)
    Smart fortwo EQ - £1,531.20 (17.6)
    Tesla Model 3 - £5,420.10 (62.3)
    Tesla Model S - £8,700 (100)
    Tesla Model X - £8,700 (100)
    Tesla Model Y - £6,525 (75)
    Vauxhall Combo-e Life - £4,350 (50)
    Vauxhall Corsa-e - £4,350 (50)
    Vauxhall Mokka-e - £4,350 (50)
    Vauxhall Vivaro-e Life - £4,350 (50)
    Volkswagen ID.3 - £5,046 (58)
    Volkswagen ID.4 - £4,524 (52)
    Volkswagen ID.5 - £6,699 (77)
    Volvo C40 Recharge - £6,787 (78)
    Volvo XC40 Recharge - £6,787 (78)

This is the price to replace the entire battery pack for these cars?

These seem _dramatically_ cheaper than I expected. In my mind, I was thinking more like 3-5x this, though that was incl VAT/tax

Post says "battery prices" so I assume that is for the material costs only. I expect labor costs to be a significant adder. It seems replacing an EV's battery would be similar in scope to replacing an ICE car's engine.

Not even close to the same amount of work. Replacing the battery pack in my PHEV, should it ever need replacing, which I doubt, involves removing 20 bolts and unplugging it. It drops right out the bottom of the car.

Ok, so stories like the guy who blew up his Model S because he was told a new battery would be $22,000 leave me not knowing what to think.[0]

Our official car dealer would happily try and charge $50 to refill the windscreen washer fluid during a routine service :) so maybe the actual cost of the battery unit is only part of the story here.

[0] https://electrek.co/2021/12/23/tesla-owner-blows-up-model-s-...

$22k for a Model S battery doesn't sound very wrong to me, but it's going to be almost all materials and not a lot of labor. The battery I mentioned lists for $5500 from Honda, and it is only 17 kW-h. A Tesla has a 50-100 kW-h pack, so I would expect the cost to be proportionately larger, with a slight discount given Tesla's large battery purchasing power.

Apart from that question, most of these are still more expensive than all repairs I've had on a gasoline car in 10 years.

These are not the MSRP prices. These are estimates based on the kWh of each battery.

I can estimate from parts that an iPhone costs $200, but it costs $1000.

So where can I buy EV batteries at those prices? Im interested in 20-30 to start with, Ill send my own lorries to pick them up.

Reply on news.ycombinator.com