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Home chargers don't need 3phase, they use a 12mm lead

They run a dedicated 30A 12mm cable from the board to the Charger as they install it.
Unless your board is very old it doesn't need a new one.
You sure about that size? It's non-standard and bigger than needed for a 32A circuit.

And even if the CU is very old, it can be easier to just install a new, small one just for the charging circuit - physical space and shonky old supply fuses that shouldn't be fiddled with are the only issues I can think of.



There's a thriving market in charger/parking space sharing (Chargy, Plugsurfing etc).
If that involves reselling electricity I'm pretty sure there are rules'n'regs to consider? Or is that only for landlord/tenant situations?
 
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So for many, you will get home, plug in, donate your excess to the grid 5.30pm to 9.30 for a good return then charge up overnight when demand is low and prices are much cheaper.
Hoping all the time that no unforseen event arises which means you need to go out again in your car which would have had enough charge had you not flogged it back to the grid...
 
If that involves reselling electricity I'm pretty sure there are rules'n'regs to consider? Or is that only for landlord/tenant situations?
I would assume it would be no different to a motorhome connecting up to a socket on a campsite.

I don't know if there are different installation regulations for a purely domestic charger and one for limited commercial use. I would think that the main problem would be insurance, are you covered if they slip on ice on a winter morning etc. I would hope that the sharing sites provide public liability insurance or the hose holder checks with their house insurance.
 
a dedicated charger will save it's cost pretty quickly in selling back electricity at peak prices and buying overnight on the cheap.
That may be a case of "watch this space". The govt are not going to just wave goodbye to all the petroleum revenue tax they currently get.
 
Haven't actually got an EV but thinking of selling up (down sizing) and installing a charger before we go, as an added sales feature.
I'd be gobsmacked if you got your money back on that. Let the new owner do it if they want.
 
That will be what they are calling the Internet of things IOT, a totally connected house and again something to avoid, would you want Alexa in total control or rely on it to ensure your house does not freeze whilst you are away, forget it still early days and I don't believe in being a guinea pig at my expense.
Seriously out of date, technology reference-wise, but still relevantly funny.

http://users.rcn.com/alderete/humor/comp/digital-home.html
 
They have one thing in common with a smart phone and that is they are not very smart!

I will avoid at all cost, already know several people that were conned into having them and none of them actually communicate readings and others that have had failed displays so you cannot even manually read them.


That will be what they are calling the Internet of things IOT, a totally connected house and again something to avoid, would you want Alexa in total control or rely on it to ensure your house does not freeze whilst you are away, forget it still early days and I don't believe in being a guinea pig at my expense.
Could connect the drinks cabinet and have G&Ts on the dot?
 
I didn't go to EV Charging System Cable and Port Design school, but all of the EVs I've seen have doors that have to be opened to access the car's charging port. A sensor on the door should easily determine if the door is open, whether or not a cable of any type is attached. I think my friend's Audi had a warning lamp on the dash if she didn't close the fuel door.
Or simply a plunger switch depressed by the connector when it's plugged in, you could probably dual purpose one of the actual charging connectors to perform this function as well.
 
With these new fangled smart meters that monitor your electricity usage why don't they use them to monitor your electricity usage and stop charging the car when you are boiling the kettle and the fridge freezer compressor is running.
In theory that sort of regime is coming. The ultimate direction of travel for smart meters and smart appliances is an integrated system to provide demand management, continuous real-time price changes, priority driven usage policies etc.


You will now need the meter to communicate with the car, these meters have issues with communicating at the best of times.
You'll need the meter to communicate with all your appliances, and they with each other and the meter. Johna mentioned a F/F compressor. Assuming you don't open the door, or open it much, there's no reason why that needs to run at all while the WM is heating the water, for example, or the kettle is on. But the F/F needs to know what the other appliances are doing.

Until then all you have is fancy remote meter reading and the ability (be afraid) for suppliers to easily implement rationing via targeted short-term disconnections.


That's great, but I was specifically referring to a discussion about chargers which respond on the fly to the usage of other appliances, such as dryers or kettles. Spectric was theorising that such chargers would need to communicate with smart meters, and I was explaining that, as far as I know, they don't.
They don't, but the papers I've read have said that that sort of thing is where (at least some) people see it going. John Brown talks about a limited electricity supply - there's a good chance that we are all going to have to deal with one of those.

your property has a limited electricity supply, and you already have an induction cooker, electric shower, ASHP heating etc.

Terry makes a number of points about how it will/could/might all hang together.

In the fullness of time (probably not far off) there will be a simple smartphone app to control EV charging which will need inputs for:
  • level of charge required - next day simple commute will justify only a 30% charge, a long journey next day may mean charging to 100%. User could always default to 100% charge anyway.
  • price per KWh - eg: charge when price is less than XXp
  • if PV fitted - prioritise - (1) household appliances, (2) car charging, (3) sale to grid
  • integrate with domestic energy tariff terms - variable 30 min charges, peak/off-peak rates, etc
  • integrate with forecast demand, weather impacts, green energy generation, pricing
This is all completely feasible. Data connectivity between house, car, electricity supplier, forecast price, weather (affects range), traffic conditions etc may need some improvement for resilient performance but is not insuperable.

Alternatively EV users can simply get home, plug in, and pay whatever it costs. Needs no internet connection (unless EV charging is taxed), but as plug in will be at a peak demand time (17.00 - 21.00 hrs) costs will be materially higher.
So you might tell the washing machine to run at some point while you are at work, when the price drops below 'x' p per unit, but at 15:00 to start looking at predicted prices over the next few hours and to book a slot with the supplier for a given number of units before 18:00 because when you get home you need the washing to be finished.

As above, the kettle pre-empts the freezer, which in turn pre-empts the dryer.

And yes - different loads might have to cost more than others to run. Electric showers might always be more expensive to run, per kWh, than an induction hob.

And yes - power to charge EVs might be priced differently to other uses. Fuel taxes raise considerable sums - they will need to be replaced. Per device usage monitoring and pricing is not a difficult technical problem to solve.
 
A house will only need to load shed if the incoming supply is limited. Currently for most houses the incoming fuse comfortably covers all demands. It is rare that the 60+ amp fuse blows!

With more EVs network capacity may fail to keep pace with demand. Demand reduction could be through (a) clear prioritisation within a household of priorities, (b) centrally mandated action to switch off certain items (eg: EVs) or (c) an increased cost per unit.

Neither (a) or (b) will be satisfactory. Some may intelligently prioritise usage to limit peak demand but cannot be relied upon by energy networks. Central control removes individual choice and is completely insensitive to individual requirements - eg: shift workers etc.

Price is probably the one which will be most effective. If folk want to charge the car at 17.30 - 21.00 and pay £1 a unit rather than £0.15 at 02.00 - 05.00 that is their choice. Folk prioritise as they see fit. All control is local using a price data feed. Other data - weather, etc - is optional.

With all change early adopters are excited to get on board before the technology is resilient. Most transition when technology approaches tested maturity. Late adopters (some on this forum) come to the party late, apprehensive, unsure, and with multiple reasons why it won't work..
 
How many chargers do you need to replace a forecourt of pumps?
Moving away from the fag-packet figures a little, 1l of petrol is 9.5kWh, 1l of diesel is 9.9 (Energy density - Wikipedia).

Assume that a pump transfers 1l/s, , that makes a petrol pump a 9.5kWh/s, i.e. 34.2MW appliance.

You need though to factor efficiency - someone earlier said 60% for an ICE. Hmm.

All-Electric Vehicles - "Conventional gasoline vehicles only convert about 12%–30% of the energy stored in gasoline to power at the wheels." OK- US cars, but 60%??

I've also heard a rule of thumb of ⅓ mechanical power, ⅓ heat, ⅓ noise.

So let's say the petrol pump is about 11MW?

Then there's efficiency the other way for an EV Where the Energy Goes: Electric Cars 60-73%?

So twice a petrol car, making the petrol pump a 22MW appliance.


Ouch.
 
I remember one trip over Hardknott Pass in my petrol car which on roads like that does less than 20mpg....

Even at 20mpg most cars will have a range of 150 miles or more. There is no excuse for running out of fuel - fuel strikes, crossing the Sahara, etc excepted. Even then it is dumb.

An EV bereft of amps is more inconvenient due to recharging duration and currently some charging network constraints. But grinding to a halt as the battery runs flat is equally dumb.

Some folk fill up the car when it is still a quarter full with over 100 miles range (like me) - those who wait for the fuel warning light and test its accuracy get punished!
 
A house will only need to load shed if the incoming supply is limited.
Load-shedding is used in France. The consumer has the choice of what capacity supply to have - the bigger it is the higher the standing charge.


Currently for most houses the incoming fuse comfortably covers all demands. It is rare that the 60+ amp fuse blows!
Particularly as it will probably pass 90A for several hurs.


Some may intelligently prioritise usage to limit peak demand but cannot be relied upon by energy networks.
But what can be relied on is a regime which tells people that either you limit your use by your actions or we will limit it to zero for you.


Central control removes individual choice and is completely insensitive to individual requirements - eg: shift workers etc.
Actually those individual circumstances can be easily accommodated. The childless couple who are are work all day can be treated very differently to the elderly person who is at home and needs an oxygen machine.


Price is probably the one which will be most effective. If folk want to charge the car at 17.30 - 21.00 and pay £1 a unit rather than £0.15 at 02.00 - 05.00 that is their choice. Folk prioritise as they see fit.
Yes- choice will be a factor, but subject to overall constraints.
 
Even at 20mpg most cars will have a range of 150 miles or more. There is no excuse for running out of fuel - fuel strikes, crossing the Sahara, etc excepted. Even then it is dumb.
Oh I'm blaming nobody but myself and expecting sympathy from precisely nobody. I live in London, and I'm conditioned to an environment where I'm never more than a few miles from a petrol station. When that changes and I don't adapt....
 
Some folk fill up the car when it is still a quarter full with over 100 miles range (like me) - those who wait for the fuel warning light and test its accuracy get punished!
Every time there's a shock to the system which results in the pumps running dry, I tell myself I'll never let the tank get less than half-full again. And that determination lasts for a while, then ebbs away, as I hate filling up.
 
Energy network operators (DNOs) plan on an average demand of just 2-3kW (8-10Amps) per household across residential areas. Yes we have 60, 80, 100A or greater fuses in our homes but we can't all draw that at the same time. EV charging by many customers at 7kW for hours at a time is not something the distribution network can support without sizeable investment. Consumers will have to pay for this. I wouldn't expect the cheap overnight tarrifs to persist as home charging becomes more widespread.
 
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