OK well use the BP chargers then if you prefer.
You need to add 5-15% to the BP prices though because they charge for AC not DC like the SuC.
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Charging efficiency and basis for payment
- Thread starter Jason71
- Start date
You need to add 5-15% to the BP prices though because they charge for AC not DC like the SuC.
I've heard this before and I'm not particularly doubting it - but would love to see a reference. If there is concrete proof of this I suspect we could get consumer rights organisations like Which? interested - and maybe even Trading Standards.
With any other commodity it would be flat out illegal to charge for a greater quantity of goods than was delivered. If that's not true for EV charging, it damn well should be.
There's also a broader public policy argument for charging for DC energy actually delivered. If rapid charger operators can get away with charging for the AC energy consumed by their charger, rather than the DC energy delivered to the car, then there's little incentive for them to buy more efficient chargers - and in turn little incentive for manufactures to invest in designing them.
EDIT: Corrected to say energy, not power
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Nick77
Deep Blue Model 3 LR (2021 MIC)
I can believe this. I get charged £15 to use BP Pulse chargers (they take it automatically at the start). And it stops automatically when that's used. My local one is 35p/kW.
I check Tessie afterwards and the energy added to the car comes to just over £13 worth.
For example:
That works out as a loss of 12% and converts to 39.5p/kW. It's a bit like filling up with regular unleaded at Shell and getting charged for V-Power.
I'd definitely send it on to Trading Standards if people thought there was a case.
Edit - I just checked and it varies from £12.84 to £14.54. Either way you don't get exactly what you pay for.
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You are charged for the energy supplied which is standard practice. Your electricity charges you for energy supplied not for the energy you actually use. All electrical appliances have a loss when converting the supplied energy whether it is light bulbs or televisions.
Energy input can never be energy output no matter how efficient your appliance/ev is.
Mr H
Active Member
so if the network chooses to install a very inefficient charger (probably because it was cheaper) then the customer has to pay for it....
I believe those efficiency losses quoted for AC charging refer to the on board charger (OBC) and battery resistance on the Tesla itself. You are charged for the energy supplied as it leaves the chargepoint into the charger cable.
That would be correct for AC charging but not for DC charging. For DC charging the losses are in the charger that is external to the car.
petit_bateau
Active Member
With the general caveat that I haven't looked at either the electrical schematics for a typical Tesla vehicle, or for a typical fast charger ...
In the past when I have looked for one, I have not been able to locate commercially available DC energy (kWh) meters that are compliant with the EU MID Directive*. Believe me at the time I looked very hard over several years, and had discussions with UK's Ofgem and with various DC energy meter manufacturers. I was contributing to various of the relevant renewable energy standards committees at the time (as a pro bono expert) and this was by no means an idle search out of intellectual curiousity. These DC energy (kWh) meters existed, but were not certified as being MID-compliant. Maybe, or maybe not, they were compliant but they were not certified. There was a catch-22 in that the device manufacturers would not go through the certification processes (and maybe redesign processes) unless there was a proven market for at least several thousand devices; but the market would not exist unless an MID-certified device existed. At one point we even considered manufacturing them ourselves and putting them through certification.
(As a work-around we could identify various alternative ways to be MID-compliant, but they required use of comparatively expensive lab-type equipment & components and so were not commercially cost-effective. What I am describing here is commercially available and economically viable (COTS) components/equipment.)
Now firstly any Brexiters can crawl themselves back in their horrible boxes, as this is still the pertinent legislative requirement in both the EU and the UK and any EEA/EFTA country, and many other countries that have adopted EU/CE standards suites. Secondly the device (i.e. the charger) must be MID-compliant in what it sells, i.e. it cannot use a non-MID-compliant meter to measure the amount of energy to bill to the customer (at least not in UK/EU/etc). Therefore unless Tesla (or any other charger operator/designer/manufacturer) have engineered (and then certified) an MID-compliant DC meter the charger must (shall) use the AC meter as being the MID-compliant meter. If so this means that any AC>DC rectification losses that occur in the charger would not be measured.
However it may be that the charger operator applies a discount to the DC channel to allow for the rectification loss within the charger. Without either carrying out testing of a typical charge cycle, or getting verification from a manufacturer, I do not know.
This is not just an issue that may be relevant to the DC car-charger market. It can also affect the DC-coupled storage market.
Of course the availability of such a certified device may have improved in the last few years, and I myself have not researched this for a few years, but a phone conversation I had fairly recently suggests not.
* = EUR-Lex - 32014L0032 - EN - EUR-Lex
Thank you @petit_bateau for a very informative answer. Seems like an astonishing state of affairs but I guess this is an area where the regulations haven't yet caught up with technology. The moment a regulation is passed requiring charge points to only bill for energy actually delivered to the customer (as will almost inevitably happen in time) a market for approved meters will immediately exist, and that will break the deadlock.
I fear we're taking the supercharger site news thread off topic, though (largely my fault - sorry!). Maybe we need a new thread for this.
I fear we're taking the supercharger site news thread off topic, though (largely my fault - sorry!). Maybe we need a new thread for this.
petit_bateau
Active Member
Actually it is the other way around, this is an area where the regulators are ahead of the technology. The top-level regulation itself is very sensible, i.e. put in place sufficiently good metering that the customer is not cheated, either by accident or on purpose. So the EU top-level regulation itself was (and is) absolutely fine.
However in the UK the problem lay in the lower level regulator and how they exploited that regulation, i.e. Ofgem. In my personal opinion - Ofgem were gleeful that no such DC MID-compliant meter existed, and frankly spiteful in refusing to allow a dispensation for what (per our/my testing) appeared to be perfectly suitable non-certified DC meters to be used in their place in order to kickstart the market. Ofgem had the authority and competence to issue such a dispensation, but would not do so.
At the time this would have enabled a lot of off-grid generators and consumers of electrical power in DC-only locations to have accessed the various UK renewables support schemes (Blue Skies, FIT, etc). Since then it would have made some things easier in the UK battery storage market, both for manufacturers and for consumers. And then MID-certification would have followed.
Anyone might think that there are people in Ofgem (and their paymasters .....) who really don't like renewables and who have abused their position over many years.
In non-UK markets I dealt with the use of non-MID-compliant DC meters was allowed by the relevant authorities.
I suspect that what you folks are observing in the DC-metering of BEV-chargers and the (possible) loading of rectification losses onto the consumer without fully transparent billing is the result of all this. It is a tangled web we weave ...
Tesla superchargers apparently have an efficiency of over 90%. Plus Tesla do not charge for the losses I think.
Tesla aren’t some kind of benevolent organisation, of course they charge, it’s just built into the price.
The issue is transparency rather than the price people actually pay. If other companies billed for DC delivered, the price per KWh would be higher because they are not benevolent organisations either.
OK I'm glad someone else has raised this subject. It's a can of worms basically.
As far as AC charging is concerned:
If you are using an AC charger that supplies 7.2kW and above the supplier must use an approved meter (MID) iaw Schedule 7 of the Electricity Act 1989 to bill you for your consumption. (If the supply is less than 7.2kW it may not need a meter)
As has been pointed out there is no metering standards for DC charging at all.
The generally accepted method is that you are billed for the AC electricity used by the charger (as described above) and this includes the conversion losses. As has been already identified this means there is no incentive for the manufacturers to use efficient rectification. There are wide variations in conversion losses from charger to charger and I have asked Which? to do a survey on this but it seems to have gone into the 'way too difficult' tray.
The government department responsible for setting a standard is The Office of Product Safety and Standard which is part of the Department for Business, Energy and Industrial Strategy. Who knew?
I cannot see them setting a standard when there are no certified DC meters around. They will look to see what is done in Europe (nothing).
What needs to be done is for companies who have higher than average conversion losses be exposed and equally those that have the lowest conversion losses be commended. Gathering the data for that will be a problem as there would need to be a testing standard and some accurate measurements to be done. Did someone mention they had a 'way too difficult tray'?
> Why do some locations bill per kWh and some per minute?
Tesla believes that owners should pay for energy delivered to the vehicle and therefore we price the service on a per kilowatt-hour (kWh) basis for the global network. In some regions, regulations and requirements make it difficult for companies that are not utilities to sell electricity for vehicle charging per kWh. In these places, we offer the Supercharger service at a per minute price, with two tiers to account for the dynamic charge rate.
Supercharger Support
Learn more about Tesla Superchargers, including best practices, charging rates, payment methods and locating a Supercharger when you're on the road.
www.tesla.com
It will be interesting to see what comes out of Q22 & Q23.
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@petit_bateau @Mr Miserable This document (don't know if it's current) seems to say that, in general, sale of electricity to an EV owner by a charge point operator is not considered to be 'supply' under the electricity acts because the EV is not a 'premises'. Would this not render the discussion about MID meters moot?
www.ofgem.gov.uk
Taking charge: selling electricity to Electric Vehicle drivers
This guide distils the different models we’ve encountered and clarifies what rules apply. This edition updates a version published in 2019, including additional charging scenarios we’ve encountered. It doesn’t cover other EV considerations such as technical standards or network connections.
petit_bateau
Active Member
Let us be clear there is a standard for DC charging, or more precisely in 'billing' for kWh of DC energy provided to the consumer at a EV charging station.
The EU MID Directive* is quite clear in this respect. The issue is that no commercially available and economically viable DC energy (kWh) measurement devices (used to) exist that were certified as being compliant with the standards set out in the EU MID. Such certified devices do exist, but they used to be too expensive to be economically viable. I am not aware that high cost of including such a widget is a valid legal defense.
(Back when I took an active interest in this matter, the way we stayed legal was by simply not selling equipment that purported to be compliant, and as a result that market segment was not served. Which was exactly what the dark inner souls at Ofgem were trying to achieve in my opinion.)
Let us also be clear, that the EU MID is still the relevant law (regulation) in the UK, Brexit or no Brexit. If anyone is unsure on the matter then go and look at the block importation of all the EU Directives into UK law so that they remained in unbroken effect. (And I'll predict that if the UK is stupid enough to change this then the UK will become industrially more irrelevant even faster than it is currently doing so.)
So .... quite what the charger vendors and the charger operators are doing to be compliant anywhere in UK/EU/EEA/EFTA is interesting. Perhaps certified MID-compliant DC energy meters do now exist that are economically viable and incorporated into the DC chargers. I really don't know as I've not stripped one down.
But I suspect the answer lies elsewhere, in some small print ........ and I personally suspect that the smallprint is not itself valid in either the UK or EU/EEA/EFTA if it were to be put to the test in court.
All of which is a real shame as I do not wish to see this used as a stick with which to beat the BEV transition that Tesla are driving forwards.
* EUR-Lex - 32014L0032 - EN - EUR-Lex
petit_bateau
Active Member
Not in my opinion, no. The MID is acting at a higher level. If you sell something to a customer , you must measure it properly (as the MID sets out). So the question is, are you selling something to a customer ...@petit_bateau @Mr Miserable This document (don't know if it's current) seems to say that, in general, sale of electricity to an EV owner by a charge point operator is not considered to be 'supply' under the electricity acts because the EV is not a 'premises'. Would this not render the discussion about MID meters moot?
Taking charge: selling electricity to Electric Vehicle drivers
This guide distils the different models we’ve encountered and clarifies what rules apply. This edition updates a version published in 2019, including additional charging scenarios we’ve encountered. It doesn’t cover other EV considerations such as technical standards or network connections.
(in some places similar issues are gotten around by selling 'time' not energy, but I have not seen that argument being deployed in the UK/EU/EEA by charger operators to address the DC issue)
(by the way, it would not be the first time that Ofgem and I have disagreed - but they do tend to mark their own homework, and always dance to their paymaster's tune)
Ok, to take a completely different tack here. The terms governing BP Pulse say
They clearly talk about "electricity supplied to you" so I would say that if they charge you for more than the "electricity supplied to you" they are highly likely to be in breach of the contractual arrangements they agreed with the customer.
Ok, makes sense. And that document does go on to say that although not governed by electricity supply rules it is governed by broader consumer protection rules.
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