Running the house from the car

Gomev

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Just seen this on the Speakev forum. Any comments from our resident electricians eg @BugEyed .

 
The man who posts as Stageshoot on SpeakEV is a knowledgeable and sensible chap, as well as a good bloke in real life.
What he's doing complies with the regs and is basically as safe as running your house off of any generator and disconnected from the grid.
The key is the mains isolation and the local Earth.
 
The man who posts as Stageshoot on SpeakEV is a knowledgeable and sensible chap, as well as a good bloke in real life.
What he's doing complies with the regs and is basically as safe as running your house off of any generator and disconnected from the grid.
The key is the mains isolation and the local Earth.
Excellent, that sounds like a good alternative to having batteries installed. I presume the cost of doing this is reasonable in comparison.

This is a car (battery) OR grid solution, so taking it further would there be any cost effective means of combining them so grid can provide cover automatically when required.
 
I don't think it will be long before V2H EVSE's come along but the above is a great solution in the meantime 🙂
 
Excellent, that sounds like a good alternative to having batteries installed. I presume the cost of doing this is reasonable in comparison.

This is a car (battery) OR grid solution, so taking it further would there be any cost effective means of combining them so grid can provide cover automatically when required.

As you say, this is currently a very manual solution and only suits certain types of Earth wiring. The other issue is that a certain amount of the car has to remain powered up so I'm not sure how secure it is and the effect on the 12v.
Considerable work would be required to make a V2G solution that provides an automatic switch over to cover all four of the scenarios of:
  • Power only from car
  • Power both from car and mains
  • Power from mains only
  • Power from mains only and car charging
There's an AC V2G standard agreed but no approved connection standard (let alone hardware) to allow it in the UK yet. But it will happen.
 
As you say, this is currently a very manual solution and only suits certain types of Earth wiring. The other issue is that a certain amount of the car has to remain powered up so I'm not sure how secure it is and the effect on the 12v.
Considerable work would be required to make a V2G solution that provides an automatic switch over to cover all four of the scenarios of:
  • Power only from car
  • Power both from car and mains
  • Power from mains only
  • Power from mains only and car charging
There's an AC V2G standard agreed but no approved connection standard (let alone hardware) to allow it in the UK yet. But it will happen.
For the 'simple' manual solution as initially described do you have a ballpark figure for installing. Obviously every property will be different but just some inkling of the area we are in. e.g £25 - £45,000 (I have used silly figures just to illustrate :) ) Thanks
 
It's probably in the £200 ballpark, but it depends on a lot of things:
  • What Earthing arrangements you currently have. You need to Earth locally (typically via an Earth rod) rather than the more common PME. If you have to add a local Earth that can be very inexpensive or very expensive depending on your local ground and the location of utilities.
  • Whether you can live within the low power provision of the MG. Stageshoot has a 7kW supply, we are typically limited to 2.5kW. He has accepted living within his limit which allows him to change the supply for the whole house which is the simplest, whereas if he were needing to split the load to allow some high current items to run from the mains but others from the car things get much more complicated. FWIW I have a boiling water tap in the kitchen which randomly pulls 12A and would likely trip the MG V2L. It would be hard to run other items in the same room (say the fridge) from a different source safely.
 
Thanks @BugEyed it makes for a very interesting train of thought. If you were in an area that suffered power cuts often this would be a great addition to have.
I live in a pretty regular house, only 2 of us and we average 5-6kWh /day (excluding charging the car), with only the hob/oven and kettle that would be over the 2.5kW.
Only real necessities to maintain normal life in the house are the fridge/freezer TV/Sky box, and router. Gas boiler for heating.
So for a few hundred quid the option to move a very high percentage of electricity usage to the Octopus off-peak price sounds pretty good.
Only down side - don't have a car with V2L. :)
 
V2L - implied no potential connection to any other generation, particularly not the mains. Stageshoot has done this differently as he disconnects the house from the mains before connecting the car and vice-versa. Note that the AC frequency generated by the car is unlikely to be in phase with the mains or even as accurate.
V2H - implied that the home is connected to the mains whilst providing some power. No export from the property occurs, and often import will happen at the same time. The phases of the AC must match exactly, the car will mirror the mains.
V2G implies that the car is exporting to the home and the grid, and hence is being controlled by the grid. Otherwise similar to V2H.
 
Thanks @BugEyed it makes for a very interesting train of thought. If you were in an area that suffered power cuts often this would be a great addition to have.
I live in a pretty regular house, only 2 of us and we average 5-6kWh /day (excluding charging the car), with only the hob/oven and kettle that would be over the 2.5kW.
Only real necessities to maintain normal life in the house are the fridge/freezer TV/Sky box, and router. Gas boiler for heating.
So for a few hundred quid the option to move a very high percentage of electricity usage to the Octopus off-peak price sounds pretty good.
Only down side - don't have a car with V2L. :)
You really need V2H - you can then use the oven/kettle without overloading the car, but only providing electricity for your house and not the grid as a whole. Of course if the potential income justified it and safeguards were in place to ensure that you could use the car when you want to V2G might be an option.
 
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