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Discussion Starter · #22 ·
Will this unit actually work for whoever buys it, though? I'm not familiar with it, but if it needs connectivity and an account to work, then isn't there a possibility that it may be worthless to whoever buys it?
Very possible, and best answered by @Mike Schooling .
 

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Discussion Starter · #23 ·
I'd rather have the three grand and not cause my car battery to deteriorate.
Each to their own. For those who lease and hand back their car battery condition is less of an issue. But will their next car have a CHAdeMO?
 

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Discussion Starter · #24 ·
Purely out of technical interest, does anyone know if these units discharged at a fixed rate or whether they could be used to balance import to zero?
 

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Not the first unit to have been sold on.

This one is actually relisted. first cropped up a few weeks ago.

We haven't got a process setup yet for how we support customers and devices after the trial but the intention is to offer support as a manufacturer. We have already shipped parts to one trial participant who's 2 years were up.

We're building a V2H optimisation at the moment which will be part of our new app. I think the most likely scenario is we'd ask for a subscription fee (think ring doorbell style) for those that aren't the original purchaser, after warranty, etc.

I have no idea if Kaluza will let you use their app or if OVO would offer the V2G tariff.

£3k is taking the **** though, I'm aware for others selling at £1k. we sell them new for not much more than £3k...

Installation involves a G98 or G99 application (we can software lock to 3.68kW export). With all of the documentation etc an install is around £1k from one of the approved installers like The Phoenix Works or ChargedEV.

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If you're just looking for ways of getting power out of a vehicle's battery pack, there's probably cheaper ways of doing it, but it's not a user-friendly or polished solution, or even safe for those who aren't power electronics engineers. Don't try this at home:

Connect ChaDeMo, stand clear, signal the car's PDU contactors to close via a microcontroller using CAN bus.
Ideally monitor state of charge with Chademo protocol.
Connect DC lines of Chademo to a suitable solar inverter (grid-tie or off-grid as required) that can take the voltage range from it's string input. Actually, don't go connecting live HVDC cables. You should have done that first.
Get microcontroller to open car's contactors again if SOC falls below a threshold.
Use existing car on-board charger to charge car when power is green / free / cheaper.

This almost certainly wouldn't pass any wiring regulations or even meet with DNO approval without a large amount of safety features (fuses, earthing, etc) that I haven't described here, but it would just about work. It might be possible to do something similar with CCS, but I have no idea what the vehicle's CCS protocol controllers would think of the vehicle's battery pack SOC going down when it was expecting it to charge ,and the vehicle may decide not to close the contactors if the SOC is already at a high enough level (fully charged). With CCS you may need to somehow spoof an input DC voltage during precharge that approximately matches the pack voltage, even if you only offer a very low current.

Safe, Cheap, Usable. Choose two.
Please, if anyone reads this...

First, dont do it.

Second, if you do, please precharge the DC before it goes into the solar inverter!

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Purely out of technical interest, does anyone know if these units discharged at a fixed rate or whether they could be used to balance import to zero?
The unit is capable of exactly this (V2H) but the OVO V2G trial was grid focused so ignored the house requirements. I've been running my own unit like this for about a year, charging overnight and load match through the day.

Here is one of our units on a sunny September day, LEAF 62 doing loadmatch with 5kW of solar. Near zero grid import.



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I'd like to know why.
Because it's a forum that generally populated by people that haven't opted for the cheapest up-front option, but instead have tried to justify more expensive purchases (BEV, Solar, Battery) on tenuous medium to long-term return on investment.

And FYI, using a vehicle battery for V2G has very little impact on battery health. You're more often than not pulling only a few kWh in a session to avoid peak charges, or to utilise excess solar after sunset. It registers as only a small fraction of a charge/discharge cycle on a BMS.
 

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Please, if anyone reads this...

First, dont do it.

Second, if you do, please precharge the DC before it goes into the solar inverter!

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My first ever EV build taught me the hard lesson that the current inrush when switching reasonably high DC from the battery pack to the controller, with its bank of high value, low ESR, commutation capacitors results in an impressive bang . . .

Second, and every subsequent, controller included a pre-charge resistor and relay. Lesson learned!
 

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I'd rather have the three grand and not cause my car battery to deteriorate.
False assumption.

One of the key outputs from our 400+ car trial over 2 years is that V2G causes marginally less battery health degradation compared to traditional charging.

Full cenex report below:


We were able to prove the theory from this WMG paper:


Super high level, you are trading time at high SOC for more throughput. The additional throughput is 'less bad' for the battery that sitting at high SOC.

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Super high level, you are trading time at high SOC for more throughput. The additional throughput is 'less bad' for the battery that sitting at high SOC.
But that assumes someone would normally be charging their car up to 100%. Therefore, the inference is that V2G will be worse for long term battery health, if previously you avoided charging up to 100% every time.
 

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But that assumes someone would normally be charging their car up to 100%. Therefore, the inference is that V2G will be worse for long term battery health, if previously you avoided charging up to 100% every time.
Read the paper and the report

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Discussion Starter · #32 ·
Mike
Thanks for all of the helpful information.
(y)
 

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@Mike Schooling Are you able to offer an opinion on whether the V2L offered by Hyundai/KIA/MG will be able to work as V2H at all in the future? A constant 2kW or so from off-peak electricity would certainly help run a heat pump, etc
 

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@Mike Schooling Are you able to offer an opinion on whether the V2L offered by Hyundai/KIA/MG will be able to work as V2H at all in the future? A constant 2kW or so from off-peak electricity would certainly help run a heat pump, etc
No. V2L is very differnt tech to V2G, V2H, etc.

essentially one is grid tied, one is islanded and unable to synchronise frequency.

The intelligence to manage the grid connection simply has to live at the installation.

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False assumption.

One of the key outputs from our 400+ car trial over 2 years is that V2G causes marginally less battery health degradation compared to traditional charging.

Full cenex report below:


We were able to prove the theory from this WMG paper:


Super high level, you are trading time at high SOC for more throughput. The additional throughput is 'less bad' for the battery that sitting at high SOC.

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Busy so yet to read the report but staying at the 'super high level' would additional throughtput also be less bad than sitting at very low SOC?

Would I be right to assume @Mike Schooling that Indra is working towards a package of exV2G (i.e. second life ex traction battery)?

It could be economic for running a household only on cheap rate electricity or cheap rate plus Solar PV.

I found that the current UK domestic consumption is an average of 7.9 kWh per 24 hours for a non-electrically heated home.

A demounted 24kWh LEAF battery as part of an exV2G might be very cost effective. (exV2G is a term I have made up as shorthand - I wait to see if it gains traction. This the post where it was first used. :) )

A larger battery from a car and bi-directional inverter might even be able to cope with most of a daily heat pump load as well in a well insulated and fairly airtight domestic building.
 

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@Mike Schooling Are you able to offer an opinion on whether the V2L offered by Hyundai/KIA/MG will be able to work as V2H at all in the future? A constant 2kW or so from off-peak electricity would certainly help...
No. V2L is very different tech to V2G, V2H, etc. Essentially one is grid tied, one is islanded and unable to synchronise frequency. The intelligence to manage the grid connection simply has to live at the installation.
Nothing stopping someone with V2L output from their car connecting up to a transformer reducing the 250V AC to say 50V AC, then rectify that and feed into a solar-panel self-synchronising inverter. Eg could use a bank of 250W micro-inverters, and simply switch these in one-at-a-time to get multiples of 250W increments fed into the house. Wouldn't be a cheap or as efficient as a proper V2H setup of course, but do-able I reckon.
 

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Because it's a forum that generally populated by people that haven't opted for the cheapest up-front option, but instead have tried to justify more expensive purchases (BEV, Solar, Battery) on tenuous medium to long-term return on investment.

And FYI, using a vehicle battery for V2G has very little impact on battery health. You're more often than not pulling only a few kWh in a session to avoid peak charges, or to utilise excess solar after sunset. It registers as only a small fraction of a charge/discharge cycle on a BMS.
You need to ask who benefits from encouraging V2G. If it was such a good idea, the power generating companies would buy and operate the batteries themselves; but why bother when you can get the public to pay for them.
I don't hold any truck with investing money in something with only a tenuous likelihood of generating a return on investment. You might as well say you'll invest in some domestic water treatment equipment so the water company can save money.
This forum is populated by a wide spectrum of EV owners and those interested in EVs, but I doubt that the majority have or will have V2G. Not that being in the majority really matters. Opinions may vary.
 

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£3,000 does seem a little steep!


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You need to ask who benefits from encouraging V2G.
The consumer if they're on an Agile tariff (that isn't at max the rest of the day.
The grid because it doesn't need additional capacity for peak periods.
The environment because that additional peak demand isn't being met by OCGT Gas, gas reciprocating and diesel generators. Also, these are often hidden in plain view of residential areas, so not just global but also local environment.

If it was such a good idea, the power generating companies would buy and operate the batteries themselves; but why bother when you can get the public to pay for them.
You've missed the point, again.

The primary purpose of the battery is to power the car. The secondary use is to support V2G. What is an energy company going to do with a bunch of cars for 23 hours a day?

I don't hold any truck with investing money in something with only a tenuous likelihood of generating a return on investment.
So I assume you only buy essential goods at the minimum expense. Can I ask what device you're using to access this website?
 

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Read the paper and the report
I had done, but couldn't see any reference to improving battery health. The only oblique reference to battery usage was the fact that 75% of the participants in the trial were (before they started in the trial) used to plugging in as soon as they got home.
 
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