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V2Grid - Bring home some company electricity?

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WannabeOwner

Well-Known Member
Nov 2, 2015
9,158
5,328
Suffolk, UK
So ... if V2Grid was available I could charge at work and then use, say, 10kWH [from teh car's battery] in the evening to power the house, and still have enough SoC to get to work the following day (depending on commute length, of course).

If I had a PowerWall I could "dump" more power, once I got home, leaving just enough SoC to get back to work the following day.

I know this is a concern of Tesla vis-à-vis Superchargers, but seems to me it could be an additional Perk for anyone charging at work.

5-days-a-week x 48-weeks-a-year x say 15p per unit comes to about £ 36 p.a. for each kWH "dumped" at home each weekday - with electric cooking / AV / Lighting etc. in the evening perhaps 10kWH is reasonable?, with static storage and a short commute maybe 20-30kWH per day is also doable? so £1,000 p.a. at the top end.

Might not be worth the hassle though - although maybe smart metering will "reward" me for not using power at peak times, so some additional benefit (or, more likely in this day-and-age, no penalty for peak time usage)
 
Is it even worth it for a few hundred quid a year? I get all to easy side tracking into spending millions to save the price of a sandwich :(

That said, I tend to charge to 100% at work on a Friday, just before leaving, to reduce the amount of charging done at home over the weekend (or more probably so that my home charging will replenish the battery enough for the weekend's activities within the 7 hours off-peak charging window). Saving 10kWH-ish of charging at the weekend is saving me, what?, 10 * 7p per unit times maybe 50 weeks of the year - so about 35 quid. Loss of earnings typing this has probably cost me a year's potential savings!!
 
@WannabeOwner - I think you are maybe missing the point of v2G - the idea is that you will maybe save a few hundred quid a year but the electric vehicle fleets will store surplus power onboard from renewables when they are almost free on windy/sunny days and make them available to your house and indirectly to the grid when demand ( and cost ) is at it's highest.
 
Yup, thanks, aware of the benefit of smoothing the grid - for that purpose I can discharge, say, 10% at peak evening usage and then charge back up again overnight (off-peak). For that I will need a smart meter, and the grid to move to the point where it can send a signal to people like me to reduce consumption (my fridge could go off for an hour) and discharge back to the grid (from my car battery) ... seems to me that UK Power is a long way from that point - although i did see a Fully Charged video recently that looked like they were asking for volunteers for a trial project - I looked at the website for the details of the trial and it said "Information coming soon" so I glazed over and didn't attempt to contact them via other means.

So whilst waiting of Smart Meters to revolutionise the grid's load :) I was just musing over whether I could steal electricity from the company!! and whether that made any sense (economic or otherwise). I think the thought was triggered by another (or maybe even the same) Fully Charged video that cars are at the locations where power is used - at work during the day, and at home during the evening, and thus they could be used to transport power to where it was being used. I'm not sure why this is a "gain" over just having a National Grid, but anyways it gave me the thought about bringing some electrons home from the office ... we've got loads of paper clips at home already :D
 
P.S. I do already steal power from work. For example, if we have a particularly mileage-heavy weekend I am highly likely to charge to 100% at work on Friday so that I get home needing less overnight charging time to replenish thereby ensuring that I can get back to 100% in the 7-hour off-peak window overnight before we set off on Saturday morning.

I suppose I could nick electrons in that way whenever I anticipate charging at home, i.e. charge car to 100% at work on any day where I will then have to do some charging at home that night. Maybe tomorrow I have a meeting where I will drive direct from home, so do need to charge at home that night (whereas normally, during the week, I only charge at work)

This is all a bit theoretical. 25,000 miles a year is about 500 quid of electricity (at a decent off-peak rate), as against around 4,000 quid for an ICE. Shaving a bit off the 500 quid for anyone who can afford a model-S in the first place is not exactly make-or-break. But maybe other cause-and-effect things, that I haven't yet considered, start to come into play as a consequence?

Chancellor is missing out on a lot of VAT and Fuel Duty, and has no means of clawing back the actual electricity I get at work (which I expect he is going to chalk-up as a Benefit in Kind before long). Maybe loads of cars charging at work is going to be way more of a strain on the gird than those charging overnight. That's about the limit of what my pea-sized brain has contemplated.
 
Chancellor is missing out on a lot of VAT and Fuel Duty, and has no means of clawing back the actual electricity I get at work (which I expect he is going to chalk-up as a Benefit in Kind before long)

It already is a BiK officially - just because of the ruling that "electricity is not a fuel" and hence it doesn't fall into the special rules for fuel benefit, it's still a chargeable benefit just like free paperclips or anything else you might have. A small employer may still be able to claim that EV charging is 'de minimis' and not bother to account for it, larger employers are already installing metering etc. so they can accurately bill people for the benefit.

Maybe loads of cars charging at work is going to be way more of a strain on the gird than those charging overnight.

It all depends how demand management pans out.

Personally, I don't believe in literal V2G (actually taking power from the car's battery back into the grid) - it's just too expensive in terms of the efficiency loss and the extra cycles being put on our expensive vehicle batteries, such that the supply companies would have to offer us a very good deal to persuade us as car owners to do it, which then makes it rather expensive storage and bad value for them.

On the other hand, managed charging makes a huge amount of sense - the car provides some kind of user interface to declare how much charge is needed for the next day's driving, and the charging is then managed to achieve that at the lowest possible cost. If the wind happens to be blowing/sun shining such that there's excess on the grid then the car will get charged more than necessary, while if the grid is short of supply then only the bare minimum of charging gets done - and in any case no charging whatever gets done at half time in the cup final when everybody puts their kettle on. This costs relatively little to implement and brings big benefits to the generators. However, it does mean that we want cars plugged in as much as possible whenever they aren't driving, and possibly means we need faster charging capacity - if charging is going to occur only when it's cheapest ( == most convenient for the generators) then it's going to occur for less of the available time and so needs to be faster when it does occur.

It's not clear who is going to be the company acting as the intermediary to make this work - the driver really needs to end up buying their energy from one supplier irrespective of whether that energy happens to be taken on board one day at home or another day at work or yet another day while in a public carpark, due the the variability of power availability and driving patterns. Companies like Chargemaster think they are going to do it; Tesla obviously has ideas of their own; and I'm sure the traditional electrical companies think it's naturally their turf and they are going to hang on to it. Interesting times ahead....