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A few sites I've stumbled across recently....

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businesses whose "money-back guarantee" has proved worthless when they have gone insolvent as the claims started rolling in

... funnily enough, the company that springs instantly to mind there (I've mentioned them previously) is Pirelli Cables - they offered iirc, 25 year warranties on their undersea high voltage cable joints .... - and were inundated with failures and in a flash, the smoking ruins of Pirelli were vacated and Prysmian arose ....

As far as Tesla are concerned I reckon that Musk's experience with the original Roadster's battery and electronics shortcomings drove him to look very closely indeed at the engineering issues. I wouldn't be surprised to hear about some kind of highly finessed reporting of battery state where the drivers see one set of figures and Tesla, internally have another set... and that the relationship between the two is a flexible one - but I am cynical and paranoid when it comes to rechargeable batteries...

IDAU

well, I'm confident I can see the distribution circuit I'm on .... it's one of a dozen at my location that are exposed on the data portal... All I have to do is, I guess, devise an on / off signal that can be filtered (correlated) to show little old me ...

Apr 12, 2024 at 5:08 PM | Registered Commentertomo

DaveS,
Well spotted. I hadn't noticed that both links involved Fenix*. Fully agree that the cause of the fire is not that important. When it comes to fires, EV batteries really can turn molehills into mountains. Also agree with your "tangent". The Scottish government wanted power: downwards, or upwards, anywhere they could get it. They're not alone.

(*)Fenix is presumably based on the phoenix, whose link with fire seems appropriate.


It doesn't add up...,
By "grid synchronisation authority" I had in mind a body whose sole purpose was to dictate the phase of the sine wave around the country in a suitably bureaucratic manner. They might come up with something linked to a well-regulated concept like UTC (until they get blindsided by a leap second). There's nobody does that at the moment because it'd be a very stupid idea. And that's why I half expect somebody's going to try to make it happen.

Certainly there needs to be somebody looking after the grid, keeping the waveform as clean as possible, and the lines below power limits, but the waveform necessarily fluctuates in frequency as load varies, so synchronisation comes down to synchronising with what's already on the line. No central authority needed.

When I worked at the NSW Electricity Commission, I recall their key rule for frequency was that the *average* should be 50Hz because so many devices relied on the AC waveform to keep their clocks accurate. I think they typically tweaked overnight generation to compensate for any drift through the previous day. (I wasn't in generation, so may be talking through my hat)


tomo,
I've been interested reading about optimal charge/discharge strategies too. Optimal longevity strategies seem to be holding (roughly) between 50 and 75% capacity. That is only 25% of the whole range, so your 200 mile battery is best recharged (to 75%) after only 50 miles. Or, alternatively, your 200 mile battery really has enough oomph for 800 miles, but a conservative charge management system only makes 200 miles available. Either seems pretty extravagant.

We'll see in due course how Tesla goes with its warranties. There are plenty of businesses whose "money-back guarantee" has proved worthless when they have gone insolvent as the claims started rolling in. It'll set quite a high-water mark if that happens with Tesla!

Apr 12, 2024 at 12:20 AM | Unregistered CommenterRobert Swan

Robert

my understanding is that Tesla Inc. are positively anal about the BMS and environmental readings for their cell packs - *far more so* than any of the competition that I've heard about.

The wins from managing mild under charging and under discharging are, as I understand it (crude) of a very high order, more than compensating for what might seem a generous warranty.... I daresay that in particular BYD are paying close attention to Tesla's battery strategies.

Sandy Munro, EEVBlog and The Limiting Factor are all useful resources in an absolute shitshow of fanboys.

idau

thanks for the monitoring link - will try to see if I can see a fan heater on my feeder!

Apr 11, 2024 at 1:38 PM | Registered Commentertomo

All grids have a grid synchronisation authority, usually known as a TSO - Transmission System Operator. They all have their mechanisms for charging out their costs to consumers. In GB these are classified as TNUoS, DNUoS and BSUoS, for high voltage transmission, lower voltage distribution and system balancing respectively. That is in addition to the allocation of billing for electricity supplied which gets refined as meter readings come in. Things like V2G and "Demand Flexibility" depend on aggregated smart meter readings made by retailers at half hour resolution. Some of the local distribution outfits now have quite detailed power flow information across their networks, and some are beginning to make information available publicly to help decide on possible new connections for demand or batteries and generation.

https://www.ssen.co.uk/our-services/tools-and-maps/near-real-time-data-access-nerda-portal/

With talk of locational marginal pricing in future such information becomes essential. So far the government has been scared to go the whole hog on LMP , which could lead to some extreme local prices (both positive and negative), talking of just regional pricing - and ToU pricing.

Apr 11, 2024 at 12:30 PM | Unregistered CommenterIt doesn't add up...

@Robert

I can't help noticing that the Ayrshire battery recycling plant that had the fire you linked to on Apr 9 is owned by Fenix Battery Recycling Ltd, the subject of one of your links provided on Apr 11. That article was dated 2021. So we know that Fenix is still operating, but can conjecture that they haven't sorted all the problems out yet. Of course, the actual cause of the fire might have had nothing to do with the EV batteries stored on site awaiting processing, but clearly the presence of these batteries in a blazing building caused big problems for the fire fighters.

Going off on a tangent, I was unaware that there is now a Scottish Fire & Rescue Service, which has apparently existed since 2013. It's funny how in Scotland, since 'devolution' services that were once devolved to regional level have systematically been centralised.

Apr 11, 2024 at 12:30 PM | Unregistered CommenterDaveS

tomo,
I wonder how it's going to go with Tesla and their 8 year battery warranty with a promise of still having 70% capacity. That's just the headlines I've read about their warranty. Perhaps there's some fine print about how many miles have been clocked up, or how many recharge cycles.

Agreed on the synch mechanism, but in these days of engineering by government edict, I wouldn't be surprised if some minister somewhere wasn't thinking of creating a "Grid Synchronisation Authority".

I looked at that battery recycler's site. Only read one article (on the challenges of EV battery recycling). A bit arm-wavy about the problems, and their plan was basically we'll work with clever people from Birmingham Uni to sort it all out. They did have an interesting factoid in there that 99% of lead-acid batteries get recycled. They claimed: that recycling rates for lithium-ion batteries could be as low as 5%. I suspect they could be substantially lower than that...

Thanks for the link to the hydro plant catastrophe. Interesting to hear what they were up to when electricity was at peak pricing. Still, what's the point of a margin of safety if you can't abuse it from time to time? (I mean the warp drive always took it in spite of Mr Scott's protestations that it couldnae)


MikeHig,
If V2G were ever to get going, there'd be a question of who pays the grid operator. Even when doing the neighbourly siphoning thing, the wires are providing a service and somebody should be paying. It would seem fair that I pay to put my power onto the grid, and my neighbour pays to receive it from the grid. I suppose this is kind of built into the low feed-in tariffs paid for rooftop solar.


DaveS,
The generators were painted green. Doesn't that take the curse off it?


On a completely different topic, here's a very good video on what exactly is going on under the covers of ChatGPT. It's by 3Blue1Brown, who does brilliant mathematical videos. I remember his earlier introduction to neural nets was very good. The new one gives an insight to the staggering amount of computation going on in ChatGPT.

Anyone who thinks this has anything to do with cognition, or the computer understanding what it's doing, might need their own thought processes looked into.

Apr 11, 2024 at 12:38 AM | Unregistered CommenterRobert Swan

Robert

I came across this hydroelectric power incident....

https://en.wikipedia.org/wiki/Sayano-Shushenskaya_power_station_accident

Quite a mess!

Apr 10, 2024 at 10:04 PM | Registered Commentertomo

MikeHig

yep, V2G is at best, merely moving the load in time. The fanboys don't see that batteries have to be recharged in a sane amount of time so that the battery's primary purpose as traction energy storage can be utilised.

I'm presently assisting with a new build eco-house and the quality of advice from eco experts and planning people has me routinely exasperated...

Man with a Porsche Taycan and a couple of acres of solar raving about how cheap his motoring is has me unimpressed....

Apr 10, 2024 at 9:47 PM | Registered Commentertomo

EVs are great for the environment!

https://www.youtube.com/watch?v=48Khw8H7c8c

Apr 10, 2024 at 6:11 PM | Unregistered CommenterDaveS

tomo; Robert: thanks for those videos - tricky business!
It's going to be interesting to see how the whole V2G thing pans out as it's nowhere at the moment, afaics.
It's often touted as part of the solution to backing up wind and solar but there's a scale problem. If we take some silly numbers, say 5m EVs each able to supply 30 kWh to the grid, that's 150 GWh. Spread over just 24 hours of a hypothetical dunkelflaute that equates to a little more than 6 GW. Yet, without gas and with almost no nuclear, the grid shortfall could easily reach 20+ GW.
Imho, V2G is a mirage.

Apr 10, 2024 at 4:57 PM | Unregistered CommenterMikeHig

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