Anyone using car battery to power house ?

[TimothyN]

Wait a minute. The UK Power guy was talking about a 13A male to 13A male. He expressed no opinion about plugging the combi boiler in to V2L, so we seem to be conflating two (potentially both dangerous, but entirely different) things.

It will be much easier to understand if we kept them separate.

 

[siteguru]

The effect is the same ... the "plug to plug" arrangement would send V2L power into the ring main circuit that it is plugged into. This still has the same earthing risk as you can't isolate the earth at the consumer unit.

So no, we're not conflating two issues - they both are risky and ill-advised, for exactly the same reason.

 

[TimothyN]

I get that, and thank you for drawing it to my attention. I have dismantled the 13A to 13A cable and will have to live without hot water in the event of the next (sadly inevitable) power cut.

But I still hold that you responded to my question about the boiler with comments about the advice I got about the 13A to 13A cable, which is conflation.

 

[MG Clive]

I get that, and thank you for drawing it to my attention. I have dismantled the 13A to 13A cable and will have to live without hot water in the event of the next (sadly inevitable) power cut.

But I still hold that you responded to my question about the boiler with comments about the advice I got about the 13A to 13A cable, which is conflation.

This thread has become a merge of 3 different threads now, so it's possible that some comments may appear in the wrong order, this could explain how a post could seem to be in reply to a different comment?

 

[Barrie]

I get that, and thank you for drawing it to my attention. I have dismantled the 13A to 13A cable and will have to live without hot water in the event of the next (sadly inevitable) power cut.

But I still hold that you responded to my question about the boiler with comments about the advice I got about the 13A to 13A cable, which is conflation.

I wired my combi boiler to a regular plug as it only draws around 150w. It was originally wired direct to my consumer unit. When we have power cuts, as we often do here in rural France, I can still get heating and hot water via my V2L extension cable plugged into my MG Marvel. I don't see any risks doing this and it works flawlessly. It's what V2L was designed for.

 

[Everest]

I don't see any risks doing this and it works flawlessly.

Hmm. Then it would appear you have no knowledge of electrical safety protection systems. Being in France you are fortunate that you are likely to have a TT earthing arrangement which makes earthing of self-generated power easier than in the UK where many houses have a TN-C-S system.

But, without neutral to earth bonding and the adding of an RCD device between your MG and your boiler you should not be powering devices that are not doubly insulated, which a boiler is not. I have already linked to the issues specifically regarding to boilers in my post #74.

You say it works flawlessly. Doh!... of course it does... until something goes wrong. I can drive my car at 70mph without wearing a seatbelt and I don't die... until something goes wrong.

It's what V2L was designed for.

No it isn't. It is what V2H or V2G is designed for, but categorically not what V2L is designed for.

As I mentioned above, you can use V2L to power a house, up to the power delivery limit of the supply, but only when the necessary protection has been put in place.

 

[MG Clive]

Thanks for your knowledgeable posts on this subject @Everest, it's good to have you here.

 

[tsedge]

I find some people are like canaries in the coal mine. Their philosophy is: "I don't really understand X, but if I try doing Y to X and it doesn't blow up, everything must be fine". Until the canary dies, all is well.

Telling them they are wrong is rarely effective, they need an actual disaster to learn.

 

[ReintjeWA]

I think there are a few aussies on here who have managed to charge a home battery using the V2L, but then the house runs off the battery not directly off the car. And I think they made some special cable thing with an RDC in it.

It’s all far above what I’m comfortable with in terms of handling electricity, and far beyond what I understand about it. But I love seeing others talking with knowledge about these subjects.

 

[Everest]

I think there are a few aussies on here who have managed to charge a home battery using the V2L, but then the house runs off the battery not directly off the car.

Correct. That would be my preferred way of powering a house from V2L if one already has solar + a low-voltage battery system installed. Search on postings from @wattmatters and @Bricktop X PWR about that for more details as they have successfully done that.

 

[wattmatters]

Correct. That would be my preferred way of powering a house from V2L if one already has solar + a low-voltage battery system installed. Search on postings from @wattmatters and @Bricktop X PWR about that for more details as they have successfully done that.

We've since moved home (March this year) and so I no longer have that option as we don't have the off-grid system any more (well I do, all the components are in the shed at our new place).

We have a new Sigenergy solar PV and battery system at our new place, so no real need for V2L anymore, at least not for home backup.

We did have one grid outage before we got the battery installed, and I ran the usual extension leads from the V2L port to power the fridge, lamps and to recharge our router/server's UPS, plus the TV for my wife. I use an RCD and current limiting breaker on the output of the V2L, although I'm not sure it would do much.

It would be great if the V2L could feed the generator input of the Sigenergy system for support during longer term outages however I'm pretty sure the car's internal E-N link would mean that's not a feasible option.

 

[TimothyN]

So, two questions of the expert panel:

1. How would I know the earthing scheme used on my rental property. Will it be on the EICR? That has been done, but I can't see it today on the agent's portal. No doubt I can ask for it if the information is there, but I'll only do that if there's a point.
2. How would a common, educated but non-expert, person like me know that the combi boiler is unsafe for V2L? I mean, it's great that we have the level of expertise we have on here, but apart from that, is there any obvious documentation to say that a coffee machine, freezer or tumble drier is OK, but a boiler is not?

 

[Martinonline]

1. You will need to ask your Electricity Network Provider.

2. The kettle, freezer etc are essentially self-contained, local and earthed via the plug: thus can be disconnected from the house's earth connection. A gas boiler can have copper water pipework throughout the house and the gas pipework is normally earthed directly to the house's earth. In addition, a fault connecting power to the boiler chassis would be transmitted throughout the house widening the possible electrocution danger area.

There are also special regulations working on gas boilers and their associated power supplies.

For more discussion, please read:

MG4 EV Forum

Discussions and information about the MG4 SE, SE Long Range and Trophy Long Range electric cars from MG

www.mgevs.com

 

[TimothyN]

I get the engineering, but that is not my question.

As an educated and not stupid owner of a V2L device, it would not have been obvious to me if it hadn't been mentioned here.

Given that V2L is consumer electronics and that this is a potentially lethal use case that could easily be done in all innocence, where is the information that it's not a great idea promulgated?

 

[siteguru]

Given that V2L is consumer electronics and that this is a potentially lethal use case that could easily be done in all innocence, where is the information that it's not a great idea promulgated?

That's a fair question ... it's certainly not mentioned in the Owner Manual (that I could see, by looking at the Discharging section).

 

[Bam Bam]

Given that V2L is consumer electronics and that this is a potentially lethal use case that could easily be done in all innocence, where is the information that it's not a great idea promulgated?

You mean the proposal to use a double-male-ended cable to connect the V2L to the home supply?

Do you think that MG should have included in the manual that such a cable is illegal in the UK and considered unsafe?

Should they also include the fact that it is illegal and unsafe to drive the wrong way up the motorway?

I think the rule with electrics is "if you don't know what you are doing, don't do it and contact a professional."

 

[TimothyN]

Oh deary, deary me, how great would it be if people read before going off on one.

This conversation is rather like talking to ChatGPT. You say "Give me an image of an aeroplane without a tiger under its wing" and all it can produce is pictures of aeroplanes with tigers under their wings. And the more you ask it to forget any reference to tigers, the more likely it is that it will include tigers in its pictures.

No, I am talking about plugging the gas combi boiler into the V2L device.

So, please, please could we forget the 13A to 13A cable and try to focus on how one should know not plug the boiler into the V2L.

I accept that there are some very clever and knowledgeable people on here who know that it shouldn't be done and why, but we are in the world of unknown knowns. If it has never occurred to you that it is any different to plug the boiler in than, say, a kettle, then how would you be supposed to know, if you don't know to ask?

 

[W12Lad]

Oh deary, deary me, how great would it be if people read before going off on one.

This conversation is rather like talking to ChatGPT. You say "Give me an image of an aeroplane without a tiger under its wing" and all it can produce is pictures of aeroplanes with tigers under their wings. And the more you ask it to forget any reference to tigers, the more likely it is that it will include tigers in its pictures.

No, I am talking about plugging the gas combi boiler into the V2L device.

So, please, please could we forget the 13A to 13A cable and try to focus on how one should know not plug the boiler into the V2L.

I accept that there are some very clever and knowledgeable people on here who know that it shouldn't be done and why, but we are in the world of unknown knowns. If it has never occurred to you that it is any different to plug the boiler in than, say, a kettle, then how would you be supposed to know, if you don't know to ask?

Totally agree.
This is really interesting stuff.
I would also like to know if there is anything else (normally in a house) apart from a boiler that we shouldn't plug into our cars?
"Your fingers" is not an acceptable answer
Also, would it be unsafe to attach many electrical items using a splitter?

 

[siteguru]

Splitter? Do you mean a multi-way extension lead? If yes then the only "unsafe" thing would be to plug in items whose total electrical load exceeds the rating of the extension lead wiring. (Which is unlikely. The V2L itself will restrict the maximum power delivered, based on a resistor value in the V2L plug).

Re. the other question - anything which would normally plug in to a 3-pin socket should be fine to connect to V2L. A boiler can get its power via a 3-pin plug and socket, but this is not normal - they're usually directly wired into a circuit.

 

[TimothyN]

A boiler can get its power via a 3-pin plug and socket, but this is not normal - they're usually directly wired into a circuit.

Ah. Mine is plugged into a 13A socket. Does that mean it's OK for V2L, or do all the same caveats apply?