EV Discussion thread

silverwhistle

zeupater said:

Depending on the vehicle's ability to supply on V2G there will be a limit on the AC power each vehicle can supply which could be lower than that at which it could charge, however, considering that most domestic charger installations are based on single phase 7kW you're likely looking at the grid borrowing a maximum of 14kWh at peak which would represent ~25%-30% of a typical 200mile range vehicle's battery capacity as mentioned ... of course, with the vehicle already being connected to the grid to support it, it's already available to have the 'borrowed' electrons replaced once the peak period has passed, so by early morning the majority of people wouldn't even notice that anything had happened ..... 

Yep, most existing IOGo users won't be worried as they know if they have specified a particular charge for the car at (say) 08.00 it will be at that level. There is plenty of leeway to make up that potential <14kWh taken.

I'm actually charging at the moment as they are giving me slots outside the 23.30 - 05.30 cheap rate, so the dishwasher is on and baking a foccaccia. But to get that I had to plug in early and set my requirements for tomorrow morning.

QrizB

silverwhistle said:

I'm actually charging at the moment as they are giving me slots outside the 23.30 - 05.30 cheap rate, so the dishwasher is on and baking a foccaccia. But to get that I had to plug in early and set my requirements for tomorrow morning.

We're the same; plugged in at 1000 and asked for ~20 kWh by 0730 tomorrow, have already charged ~16 kWh during the afternoon surplus period. And done a load of laundry, and heated a tank of water!

(I'm not entirely sure that electricity at 7p is going to cost me less than gas at 5p, but for the sake of 5 kWh I'm risking no more than 10p.)

JKenH

QrizB said:

silverwhistle said:

I'm actually charging at the moment as they are giving me slots outside the 23.30 - 05.30 cheap rate, so the dishwasher is on and baking a foccaccia. But to get that I had to plug in early and set my requirements for tomorrow morning.

We're the same; plugged in at 1000 and asked for ~20 kWh by 0730 tomorrow, have already charged ~16 kWh during the afternoon surplus period. And done a load of laundry, and heated a tank of water!

(I'm not entirely sure that electricity at 7p is going to cost me less than gas at 5p, but for the sake of 5 kWh I'm risking no more than 10p.)

If you had been on Agile charging your car and heating your water would have cost you virtually nothing. I often wonder if those who only do 100 miles or so a week in their EVs wouldn’t be better off on Agile, for the summer months at least. Most weekends have had some very cheap slots.

QrizB

For us, there's not much in it. Last month's electricity bill was £25.80, of which £13.62 was IOG standing charges. The Agile standing charge is higher and would've been £19.29; even if all ~100kWh of import had been free, we'd only have saved £6.51.

Grumpy_chap

zeupater said:

the issue is to use the EV capacity to support the grid at exceptional peak demand times, so likely around a couple of hours in the early evening every so often (probably around 18:00-20:00 in most cases).

(in addition to the obvious solution of not plugging the car into the charger!)

With EDF Sunday Saver, the times to reduce daytime consumption are 4 pm to 7 pm.  I assume that time doe s not vary between region / supplier?

As for the "not plugging in" when on a V2G offering, do the terms of the offerings where the electric company are seeking to take control not require the V to be plugged in for a certain amount of uptime?  Otherwise, this could be rather moot if the V supply can be overridden by the local operator simply unplugging.


On a different subject I am grumpy about a poor charging experience yesterday.  Set to arrive at a destination with 9 of 16 stalls expected to be available on arrival.  As I drew in there are only 2 stalls available, which is still sufficient.  Except some one has kindly parked a Corsa over two bays.  I parked up in the one remaining bay only to fins that the adjacent bay is occupied by some VW driver who has plugged in using the incorrect stall so, also taking up two bays.  I wait until a bay becomes available and get to set my charge going.  Obviously, because of the busy centre, the charge rate is slow and my stop actually took ages.  Went in for a coffee and sandwich, which we wanted in any case.  Still not charged so, for the first time ever, ended up sat in the car waiting for a charge to conclude

by the time we finished, the adjacent bay was vacant, but the next but one in use by a VW-driver who had also plugged in with the wrong stall.  A TM3 driver parked up and found the same annoyance as I did - I said I'd move on as I had enough to continue and released the bay for another use.  So, a wait for a bay, a slow charge, and ended up waiting to not even complete the amount of charge ideally required.

JKenH

QrizB said:

For us, there's not much in it. Last month's electricity bill was £25.80, of which £13.62 was IOG standing charges. The Agile standing charge is higher and would've been £19.29; even if all.~100lWh of import had been free, we'd only have saved £6.51.

At least you have done the sums. Would that be the same if you didn’t have solar panels? 

I don’t have an EV so can’t access IOG but I do have solar panels which cover most of my use so I don’t benefit as much from agile as I could without. I have, though, enjoyed lower evening and overnight costs than on a variable tariff or indeed if I had been on IOG as I don’t have batteries. I do have a portable battery power pack which helped me through when teatime rates popped over 50p one day. 

QrizB

Grumpy_chap said:
As for the "not plugging in" when on a V2G offering, do the terms of the offerings where the electric company are seeking to take control not require the V to be plugged in for a certain amount of uptime?

The tariff T&C require that you plug-in for a certain number of hours a week, but I don't think they say which hours they should be. I shared a link to the T&C somewhere ...

Sorry to hear about your poor charging experience. Hopefully it continues to be a rare and noteworthy occurrence.

JKenH said:

QrizB said:

For us, there's not much in it. Last month's electricity bill was £25.80, of which £13.62 was IOG standing charges. The Agile standing charge is higher and would've been £19.29; even if all.~100lWh of import had been free, we'd only have saved £6.51.

At least you have done the sums. Would that be the same if you didn’t have solar panels?

I don't really know how much electricity we'd be using without solar. We've had them for 13 years now (we're over the half-way point on the FIT!) and so much has changed that looking back to 2011's electricity use doesn't seem especially relevant.

Maybe an extra 5kWh a day, so another 65kWh on top? If we pro-rata the IOG tariff, it would be 16kWh at 7p and 49kWh at 29p so an extra £15.33. Total non-solar-counterfactual import cost £21.84 for 165kWh, average price 13.2p/kWh.

We might have beaten that on Agile, if we could've arranged for EV charging on cheap Agile days - but that's not always convenient.

For example we put 21kWh into the car on the 18th of June arriving home on ~10% SOC the night before. Agile prices on the 18th looked like this:

I guess we'd have paid at least 16p that day, on average, or possibly more? The night before and the day following were both more expensive, and a car with 10% SOC isn't so much a means of transport as a driveway ornament.

So I still don't think there's much in it, for us at least. Other households might do better with Agile.