Using EV batteries to power your home etc V2H and V2G

[soupdragon1]

Anyone with their finger on the pulse know when we might see this in the UK?

I know VW were trialing this, where you plug your car in at home and the solar panels or indeed, the cheap night time tariff, charged the car, and then you used that to power your home from the car when electric was expensive, or when your solar wasn't generating.

VW announced that their 77kwh cars with software 3.5 or higher are capable of doing this but that's as far as I know. I got solar earlier this year, got a hybrid inverter installed so that my system is 'battery ready' but I'm reluctant to buy batteries to put in my loft. I would much rather use a car.

Anyone know if the UK is going to be supporting this type of bi-directional battery management via the car?

[mikey_b]

I hope so. Would be very useful in powercuts too, especially if it can be made seamless (like a big whole-house UPS).

I would have thought the power industry would be quite keen on it too, with things moving towards a renewables-based generation system, inherently more variable in output. Having a huge pool of batteries on-line to help match demand and supply must surely be helpful here? Maybe give discounts for making your car available to top up the grid? Be able to set max outflows or minimum remaining charge levels, so you don't get in your car in the morning and find that instead of charging up overnight, all the remaining juice had been sucked out of it right before you leave home...

[soupdragon1]

mikey_b said:

I hope so. Would be very useful in powercuts too, especially if it can be made seamless (like a big whole-house UPS).

I would have thought the power industry would be quite keen on it too, with things moving towards a renewables-based generation system, inherently more variable in output. Having a huge pool of batteries on-line to help match demand and supply must surely be helpful here? Maybe give discounts for making your car available to top up the grid? Be able to set max outflows or minimum remaining charge levels, so you don't get in your car in the morning and find that instead of charging up overnight, all the remaining juice had been sucked out of it right before you leave home...

yes, and its all technically possible too, so I'm hoping its a matter of when, not if. With lower energy demand during the night, it's ideal for the energy companies to then top up the car battery with any excess and then take it back when they need it. Its got to stack up economically too, so that the car owner is rewarded properly, and also to account for any battery degradation, which in theory, should be minimal. A full days electric usage for a typical household is only about 40 miles of range for example.

[phil4]

The DNO round here (Southern and Scottish) seems to ban battery export. They only want solar.

If you have a hyrbrid inverter they can't really stop it... but a standalone installation will get forbidden. V2G then not so good.

But V2H is possible with the added benefit that the car is there while you use most of your house usage, as you're there.

[ashenfie]

I think since solar systems home batteries have hugely dropped in price the idea has faded away.

[soupdragon1]

https://support.myenergi.com/hc/en-gb/articles/151...

So Zappi are working on a V2G charger which will be released next year:

"We have started development on our own what we believe is likely to be the UK’s first mass-market Vehicle-to-Grid (V2G) electric vehicle charger that can integrate with the rest of the home, with plans to launch the new premium product in 2025 to coincide with many mainstream V2G-enabled electric vehicles coming to market."

I'm hoping as an existing Zappi customer, they might go easy on me on price for an upgrade, like mobile phone companies upgrading your old phone lol (wishful thinking)

In other good news, VW have released software 3.7, initially rolled out to 1,000 vehicles prior to the mass roll out, which will enable bi-directional charging. At this point, its only the cars with the 77kwh battery that will be V2G capable (mine is the medium sized battery, boo)

Pistonhead man maths calculator has confirmed that its cheaper for me to change the car and use the car for my solar/night tariff energy set up than buying dedicated batteries
Honest, the calculator never lies

Good news overall though, seems like things are moving in a nice direction for those who would find a use case for such a set up.

Edited by soupdragon1 on Tuesday 8th October 16:12

Edited by soupdragon1 on Tuesday 8th October 16:13

[oop north]

soupdragon1 said:

https://support.myenergi.com/hc/en-gb/articles/151...

So Zappi are working on a V2G charger which will be released next year:

"We have started development on our own what we believe is likely to be the UK’s first mass-market Vehicle-to-Grid (V2G) electric vehicle charger that can integrate with the rest of the home, with plans to launch the new premium product in 2025 to coincide with many mainstream V2G-enabled electric vehicles coming to market."

Very please to read this - will be getting when available though will have to change my car (bmw iX) for something that can send energy to the house. I do have home battery already but the solar and wind turbine generate too much for the house to absorb immediately, and in the last few days the battery has emptied too quickly, so extra storage would be good

[OutInTheShed]

The world has moved on.
Two years ago the cheapest way to buy kwh of cells retail was to plonk an electric Astra on your drive.

Now you can buy LifePO4 cells retail at under £100 per kWh from Fogstar.
Better chemistry good for many thousands of cycles.

If the trend continues, the market place will look quite different in another couple of years.

[soupdragon1]

OutInTheShed said:

The world has moved on.
Two years ago the cheapest way to buy kwh of cells retail was to plonk an electric Astra on your drive.

Now you can buy LifePO4 cells retail at under £100 per kWh from Fogstar.
Better chemistry good for many thousands of cycles.

If the trend continues, the market place will look quite different in another couple of years.

I had a look at fogstar and their cycle stats are sort of mid range compared to some other battery suppliers, but I guess the competitive price still makes them a great choice. I'm a little nervous about storing batteries in my loft though, and would much rather have the batteries on the driveway if possible. I don't know if I'm just being a bit silly in that fire risk department and before anyone asks, no, I don't read the daily mail!

[Amateurish]

I've got V2G at home which was installed as part of a trial. It is useless though since my supplier doesn't allow me to sell energy back to the grid.

[OutInTheShed]

Amateurish said:

I've got V2G at home which was installed as part of a trial. It is useless though since my supplier doesn't allow me to sell energy back to the grid.

Is that 'it's useless because you've chosen a supplier who doesn't wish to buy your energy'?

[OutInTheShed]

soupdragon1 said:

I had a look at fogstar and their cycle stats are sort of mid range compared to some other battery suppliers, but I guess the competitive price still makes them a great choice. I'm a little nervous about storing batteries in my loft though, and would much rather have the batteries on the driveway if possible. I don't know if I'm just being a bit silly in that fire risk department and before anyone asks, no, I don't read the daily mail!

It's hqrd to know the basis of quoted cycle lives.

It ranges through 'guaranteed < Warrantedy < typical < hopeful < wishful ...' or something.

And 'end of life ' can be defined in many different ways.

I would prefer not to store big lithium batteries of any flavour indoors, but the PO4 flavour is a lot safer.
I guess that most people with a drive to charge on could have a little shed or battery banker?

To be signifcant in grid terms, I think we are talking about far in the fuure when most cars are EV.

In the meantime 'VxG' covers a range of stuff where the 'grid' controls when a car is charged, which we are already seeing I think, with tariffs where you car is charged up 'some time overnight' at a rate to suit the supplier or when it's cheapest.

It's not so long ago that Octopus tariffs were not much more complex than Economy 7.

[Amateurish]

OutInTheShed said:

Amateurish said:

I've got V2G at home which was installed as part of a trial. It is useless though since my supplier doesn't allow me to sell energy back to the grid.

Is that 'it's useless because you've chosen a supplier who doesn't wish to buy your energy'?

No because it was the supplier who carried out the trial and installed the v2g charger (British Gas)

[soupdragon1]

Amateurish said:

I've got V2G at home which was installed as part of a trial. It is useless though since my supplier doesn't allow me to sell energy back to the grid.

That's not a sustainable model though. Even me with just a basic solar installation can sell energy back to the grid so this trial seems to be the exception, rather than the rule.

[soupdragon1]

OutInTheShed said:

I guess that most people with a drive to charge on could have a little shed or battery banker?

Yes, never thought of a side shed, good suggestion.

Good to see you living up to your username

[OutInTheShed]

soupdragon1 said:

Amateurish said:

I've got V2G at home which was installed as part of a trial. It is useless though since my supplier doesn't allow me to sell energy back to the grid.

That's not a sustainable model though. Even me with just a basic solar installation can sell energy back to the grid so this trial seems to be the exception, rather than the rule.

The 'sustainable model' is that 'the grid' has control and takes power when it's needed, rather than the punter choosing to sell power when they think they can make a few quid.

The trial will have been some sort of experiment, not a 'solution' to please the customer.
In the short term, a few consumers get chucked a few sweets to persuade them to cooperate.

[halo34]

Being stupid here - can you currently use a vehicle to store energy and feed it into the house w/o selling back to the grid?

[OutInTheShed]

halo34 said:

Being stupid here - can you currently use a vehicle to store energy and feed it into the house w/o selling back to the grid?

Fundamentally, two ways of doing that.
You can get a 230V inverter built into the car, so the car can put out 230V AC.
Or you can access the DC battery and have an inverter outside the car.

Depends what you want from it?
Emergency back up power? I could even power a freezer and my gas central heating from an inverter from my diesel car.

Frequent 'time shifting' to play games with cheap and expensive tariffs?
The slightest hint of wear and tear on your car's battery would make this a bad idea.
Home batteries have got a lot cheaper over the last two years if you want to play this game, but the way things are going, I think the structure of 'cheap electricity at night' may not last forever, it will be more 'cheap electricty and unpredictable and inconvenient times.

[halo34]

OutInTheShed said:

Fundamentally, two ways of doing that.
You can get a 230V inverter built into the car, so the car can put out 230V AC.
Or you can access the DC battery and have an inverter outside the car.

Depends what you want from it?
Emergency back up power? I could even power a freezer and my gas central heating from an inverter from my diesel car.

Frequent 'time shifting' to play games with cheap and expensive tariffs?
The slightest hint of wear and tear on your car's battery would make this a bad idea.
Home batteries have got a lot cheaper over the last two years if you want to play this game, but the way things are going, I think the structure of 'cheap electricity at night' may not last forever, it will be more 'cheap electricty and unpredictable and inconvenient times.

Yeah I did wonder that bit about "cheap" electric lasting too long.

That being said - my EV comes with a "socket thingy" so if I get desperate for a warmed up microwave meal in a power outage, I got it worked out

[mikey_b]

OutInTheShed said:

halo34 said:

Being stupid here - can you currently use a vehicle to store energy and feed it into the house w/o selling back to the grid?

Fundamentally, two ways of doing that.
You can get a 230V inverter built into the car, so the car can put out 230V AC.
Or you can access the DC battery and have an inverter outside the car.

Depends what you want from it?
Emergency back up power? I could even power a freezer and my gas central heating from an inverter from my diesel car.

Frequent 'time shifting' to play games with cheap and expensive tariffs?
The slightest hint of wear and tear on your car's battery would make this a bad idea.
Home batteries have got a lot cheaper over the last two years if you want to play this game, but the way things are going, I think the structure of 'cheap electricity at night' may not last forever, it will be more 'cheap electricty and unpredictable and inconvenient times.

You'd need a pretty chunky inverter to run a freezer - don't they have quite a pull, as the compressor starts up?

It will be interesting to see how the pricing structures change. Whilst most people will want to charge their cars overnight, very few will need to pull the full ~70kWh their batteries can take every day. Probably less than 10kWh for most people. Maybe we will be able to plug the car in and leave it to take advantage of the constantly fluctuating wholesale price - you could set your charger to constantly monitor the supply cost and squirt some juice into the battery if and when the price drops below a certain rate. You could get some real flexibility here - set rules like 'always charge to 80% if it's got less than 30% when plugged in' whilst also setting other rules like 'top up to 100% if price falls below 8p/kWh', 'top up to 75% if price falls below 15p/kWh', 'stop charging if >50% charged and price rises to more than 18p/kWh. You could avoid trouble getting to work with a higher priority rule 'always charge to 90% before 8am Mondays and Thursdays'.

That would be a truly useful way to take advantage of the capabilities of smart meters, instead of spending billions of pounds on rolling them out on the premise of 'you don't have to manually submit a reading'.