Get paid to charge your Tesla....

[LukeT]

Developing my point above a bit further, these tariffs are going to be about much more than just day and night and evening peak pricing. We know the difference between wholesale price for a high wind half hour metering period vs for a low wind one is growing and will become very large, and I think these tariffs are really about that.

Historically, power price fluctuations have been more about demand, hence E7, which can be on a daily schedule rather than reactive. Increasingly, it's about supply of intermittent power, so has to be reactive to that, which is predictable over a few hours or days but isn't on a daily schedule.

Utility scale load balancing plants are likely to become much bigger news soon and battery (could be EV and immersion heaters, maybe other things too, as well as expensive house batteries) equipped homes can also provide a highly reactive load balancing service in a similar way. Whatever/whoever provides this service is a really important enabler for more renewables and therefore further decarbonisation of the grid.

It's also very early days in the market for these tariffs, little competition so they'll be priced accordingly. They should come down relative to both variable and E7.

On smart meters, whether you like or loathe them some sort of technology is required to enable end users to react quickly and automatically to changes in power price, and to be charged accordingly. I'm not sure whether their unpopularity is about "big brother", shonky implementation or something else - some of these concerns can be fixed, some I guess not.

 

[ACarneiro]

It’s interesting that the European interconnectors still show we’re buying a load of electricity from the mainland, even though we’re paying people to take the surplus wind generation.
Are the contracts that inflexible that they don’t allow reduced imports on a short(ish) notice?

 

[Glan gluaisne]

It’s interesting that the European interconnectors still show we’re buying a load of electricity from the mainland, even though we’re paying people to take the surplus wind generation.
Are the contracts that inflexible that they don’t allow reduced imports on a short(ish) notice?

I believe that there's a fair bit of over-generation from wind power in Northern Europe more generally, so suspect that the interconnect flows are part of the wider European grid balancing conundrum. Yesterday the interconnects were exporting to Europe, as a part of the effort to balance our grid, largely as a consequence of high levels of wind generation. Today it looks like we're in a better position, as we're running more gas and coal generation. My guess is that the grid is keeping the latter running mainly as spinning reserve, possibly in case we have a rapid drop in wind generation.

 

[Jason71]

I worked out the actual yearly cost of Agile based on 2018 data they supply and over the year the electricity cost in the standard E7 period 'average' cost was 10.5p per kWh versus 8p per kWh for standard E7 from Bulb.

The peak time 'average' was also more expensive.

Similarly their GO tariff is only cheaper than E7 if only every charge in the 4hr period, which if you do large number of miles doesn't quite work. E7 with Bulb anyways also extends into 830am in summer time, covering a big chunk of waking up electricity use from Kettles/toasters etc.

Octopus has really nailed their marketing, as their 'cheap' headline rates grab the attention. But overall cost is very similar to standard E7 if not more expensive, however with more hassle.

For a true cost comparison I wonder if someone could upload their recent Octopus bill on Go or Agile that way we can get a true comparison versus standard E7?

The Elephant in the bulb room is that a lot of people buying EVs are not traditional E7 customers. Bulb will not fit you an E7 meter or supply E7 rates via a smart meter right now so Bulb E7 is not even an option for many of us. Octopus's might be a bit slow to supply smart meters on some occasions ( not necessarily their fault ) but they do seem to be trying.
Others may fit E7 meters,, I have not researched extensively, but everyone is reluctant since they are all being judged on Smart meter installation they don't want to waste time on that as far as I can tell

That aside surely you can see why the Go Tariff works for a lot of people?

It may vary by location but for me
Octopus go day rate is 13.7p/kwh vs 15.7 for bulb e7
Octopus go evening rate is 5p vs 8.5 for bulb e7
Octopus standing charge is 25p vs 20p for bulb e7

So aside from the standing charge difference which is about £18 annually in Bulbs favour, as as someone with gas heating, as I don't require more than 28kw/h per day for the car then Octopus Go is cheaper irrespective of the day savings and most people don't do the 80 to 110 miles per day that this would give them.
Also if I did need to charge outside of the night time it may well be during peak in which case Octopus scores better again.

So it's not hard to see why Go works for a lot of people. And it you don't have the E7 meter then it seems like a no brainer ,even without the obligatory £100 referral you get to split with Roy!

 

[Yev000]

I'm waiting to switch to agile to give it a go... But do wonder how I can make best use with a Tesla WC.

I can't do E7, no E7 meter, noone wants to install it, Bulb don't want to install my smart meter due to gas meter being semi concealed...

 

[S.Badger]

I'm waiting to switch to agile to give it a go... But do wonder how I can make best use with a Tesla WC.

I can't do E7, no E7 meter, noone wants to install it, Bulb don't want to install my smart meter due to gas meter being semi concealed...

You can make best use of Agile and overnight charging in a few ways. Octopus list the overnight prices day ahead on their website so you can look at those and figure out the cheapest time to charge. You can also use their api to automate that calculation if you are that way inclined. There is also a third party service (in beta) that will integrate with Octopus and Tesla api and charge each night at the cheapest rate while ensuring you are fully charged by your departure time. Ive been just setting scheduled charge for 1am and hoping it actually charges at more than 16amps each night (which it often doesn't but that's another story, thread and firmware bug)

 

[Glan gluaisne]

I got around the E7 meter fitment problem by getting it changed whilst we were still with SSE. We went with SSE purely because they are also our DNO here, so it was handy for the TBS, but once we'd finished the house there was no point in sticking with them. They did fit an E7 meter within three or four days of making the request, FOC. Once the new meter was in we switched to Bulb, as they were cheaper.

There's unlikely to ever be a "one size fits all" best tariff, as so much depends on the usage profile. Go would be ludicrously expensive for us, as we just can't load shift enough into the 4 hour (or 5 hour) window. Agile is likewise about 20% more expensive for us at the moment (based on usage since Agile was introduced). I suspect that, after a full winter, Agile may well be a fair bit more than 20% more expensive for us (our day time usage for ~6 - 8 months of the year is reduced a lot by a fairly large PV array).

As for making use of charging during the Agile cheaper rate periods, using charge point control, that may be a challenge at the moment. My initial testing seems to show that the Tesla may be slightly non-compliant with the charging protocol. It should wake up when presented with an advertised charge rate on the Control Pilot, and then request power. It doesn't seem to, as there seems to be an issue with the car not waking up the charging circuit from a Control Pilot signal when it's in a deep sleep. This makes charge point controlled charging a bit problematic, I'm finding, as it will only work reliably if the car is at least partially awake.

I may have a work around, but it's not one that could be used with a standard charge point. I've found a design note from an EVSE manufacturer that refers to an unofficial wake up protocol, so am planning to change the firmware in one of my charge points to see if that gets around the problem.

 

[hmy7k]

It doesn't seem to, as there seems to be an issue with the car not waking up the charging circuit from a Control Pilot signal when it's in a deep sleep. This makes charge point controlled charging a bit problematic, I'm finding, as it will only work reliably if the car is at least partially awake.

I have a Zappi and I have the same issue. Apparently Tesla are aware of the issue and it will be sorted in a future release.
It does work if you leave sentry on when you want to schedule a charge.

 

[Yev000]

There is also a third party service (in beta) that will integrate with Octopus and Tesla api and charge each night at the cheapest rate while ensuring you are fully charged by your departure time

That's interesting, something like TeslaFi that will manually start/stop charge but according to rates?

I don't actually need to charge every day at the moment as I get free 3 pin plug at work. I just charge on weekends.

I wish the Tesla wall battery was a lot cheaper... 8k is just silly money. But that would almost cap your rate to something like 8p even without solar.

 

[Glan gluaisne]

I have a Zappi and I have the same issue. Apparently Tesla are aware of the issue and it will be sorted in a future release.
It does work if you leave sentry on when you want to schedule a charge.

Thanks for another data point - others have reported much the same, it seems, but mainly from owners in the US. I was slightly suspicious at first that it may have been the code in my home-made EVSE, but I've spent a few hours verifying that it is 100% compliant with the protocol in every respect. It also seems that the refusal to accept an advertised charge rate when it's asleep may be a Model 3 specific problem. Tesla have apparently been aware of this since last year, so they seem to be damned slow at fixing it. Makes me wonder if there is a software fix possible, or whether they've cocked up the hardware on the M3, such that the OBC protocol controller is physically turned off when the car's asleep, and so unable to turn itself on when a charge point advertises that current is available.

In the process of trying to get to the cause of this, I have also learned that the Tesla UMC does a slightly odd thing. When the CP is loaded to the "plugged in" state, instead of advertising the actual max current available, for the first five seconds it advertises with a duty cycle of about 3.2%, which, according to the standard protocol is an instruction to use DC charging, with digital signalling (i.e. the protocol used by fast chargers). This is really weird, as that protocol only applies to fast chargers, not AC charge points. After five seconds the duty cycle increases to a value within the normal range, as set by the inlet connector cable plugged in to the UMC.

I've never seen any other charge point/EVSE exhibit this behaviour, and it suggests that it's something unique to the Tesla UMC (this signal is generated by the UMC, the car just passively loads it). I've no idea what it does, but one thing I'm planning to try is to change the code in my unit so that it exactly simulates the CP signal from the UMC. It may be non-standard, and may result in my charge point being non-compliant with IEC61851/J1772, but I've been wondering if this five seconds of oddball signalling may wake the car up if it's asleep.

For the sake of an hour or so writing and testing some code I think it has to be worth a try. I'd very much rather have charging under control by the charge point than the car, for a host of good reasons.

 

[NewbieT]

I understand you want to control it all from the charge point which is fair enough. If you just want it to work () and don’t want to wait for some mythical development (!!) and given you can write code perhaps try the Tesla Unofficial API. I send a wake command to the API, wait 45s then send a charge command. Works a treat for me.

 

[LukeT]

I believe that there's a fair bit of over-generation from wind power in Northern Europe more generally, so suspect that the interconnect flows are part of the wider European grid balancing conundrum. Yesterday the interconnects were exporting to Europe, as a part of the effort to balance our grid, largely as a consequence of high levels of wind generation. Today it looks like we're in a better position, as we're running more gas and coal generation. My guess is that the grid is keeping the latter running mainly as spinning reserve, possibly in case we have a rapid drop in wind generation.

After many months over the summer of no coal use I was a bit surprised to see it running in a period when relatively little of our gas was running. I had understood gas to achieve the spinning reserve job, perhaps wrongly?

 

[Glan gluaisne]

They seem to use both gas and coal, not 100% sure why. I believe coal has a longer start up time, so it may be something related to how fast they believe things may change. There were some times during the summer when almost all generation was coming from renewables, yet they were still firing up the coal stations from time to time.

 

[Glan gluaisne]

I understand you want to control it all from the charge point which is fair enough. If you just want it to work () and don’t want to wait for some mythical development (!!) and given you can write code perhaps try the Tesla Unofficial API. I send a wake command to the API, wait 45s then send a charge command. Works a treat for me.

I'd rather try and keep things simple, and carry on using the charging system I've been using for the past 6 years. I have a three position switch on the charge point, that selects either off, on only during the E7 off peak period, or on all the time. This has been dead easy and foolproof, as when I unhook the cable I can just flick the switch to the position needed. Being able to gracefully turn off the charge point is also really useful, both for terminating a charge and for unlatching the connector (something else that doesn't seem to work with the way Tesla have done things).

My work around for the E7 thing at the moment is to have the car set to start charging a few minutes after the start of the E7 slot, and then use the charge point to terminate the charge, if it's still running, at the end of the E7 slot. This seems to work, but is a bit inflexible, as instead of just flicking the switch on the charge point to charge immediately, I have to faff around changing the car settings. Having to fire up something in order to talk to the car when I need to would probably take longer than getting in it and changing the settings.

The other snag is that I have to manually turn the charge point on to charge immediately when I plug in, and then wait until the car has done its thing and shut down, before I can flick the switch on the charge point to the timed position. It seems that the car needs to turn the charge point on to verify something before turning it off again.

 

[LukeT]

I'd rather try and keep things simple, and carry on using the charging system I've been using for the past 6 years. I have a three position switch on the charge point, that selects either off, on only during the E7 off peak period, or on all the time. This has been dead easy and foolproof, as when I unhook the cable I can just flick the switch to the position needed. Being able to gracefully turn off the charge point is also really useful, both for terminating a charge and for unlatching the connector (something else that doesn't seem to work with the way Tesla have done things).

My work around for the E7 thing at the moment is to have the car set to start charging a few minutes after the start of the E7 slot, and then use the charge point to terminate the charge, if it's still running, at the end of the E7 slot. This seems to work, but is a bit inflexible, as instead of just flicking the switch on the charge point to charge immediately, I have to faff around changing the car settings. Having to fire up something in order to talk to the car when I need to would probably take longer than getting in it and changing the settings.

The other snag is that I have to manually turn the charge point on to charge immediately when I plug in, and then wait until the car has done its thing and shut down, before I can flick the switch on the charge point to the timed position. It seems that the car needs to turn the charge point on to verify something before turning it off again.

There is of course a cost implication but I think teslafi or a 3rd party app could solve this in one.

 

[Glan gluaisne]

There is of course a cost implication but I think teslafi or a 3rd party app could solve this in one.

Yes, I'm sure this could work, but it means having to fire up a PC or, perhaps, a 'phone, and that would often take longer that just going out to the car and changing the settings, and would be way longer than just flicking the switch on the charge point (if that worked as it should). My 'phone is rarely ever turned on, as we don't get a signal here and the thing is really only kept for emergency use when out and about (used to live in the glove box of every other car I've owned!). Likewise, there are times when the PC will be switched off, and having to turn that on and wait for it to boot, just to change a setting in the car seems a long winded way to do things.

 

[gangzoom]

So it's not hard to see why Go works for a lot of people. And it you don't have the E7 meter then it seems like a no brainer ,even without the obligatory £100 referral you get to split with Roy!

Bulb fitted our E7 meter for free, so I didn't realise they had stopped doing E7. For our use Go is expensive than E7, and with a PW where often we are getting through the whole 13kWh in the PW in one day its even more noticeable. The few hours extra on E7 especially in the morning period does really make difference for us of having to use 0kWh 'peak' electricity.

I've done quite a few calculations and I cannot get the numbers to work for Go or Agile versus Bulb E7. Here is our bill in November for Go, I would to see some how people Go/Agile bill looks like to convince me otherwise.

[

 

[Jason71]

Bulb fitted our E7 meter for free, so I didn't realise they had stopped doing E7.

That's what it says on their Website and I don't think they are alone . I think they are all under pressure to fit as many smart meters as possible. I guess time spent fitting an e7 meter is time that could be used to fit smart meters. Also if you tell Someone they can't have e7 maybe they will go smart instead so that's another 'win'.

 

[Glan gluaisne]

That's what it says on their Website and I don't think they are alone . I think they are all under pressure to fit as many smart meters as possible. I guess time spent fitting an e7 meter is time that could be used to fit smart meters. Also if you tell Someone they can't have e7 maybe they will go smart instead so that's another 'win'.

When I asked SSE for an E7 meter they applied a lot of pressure for us to have a smart meter. At the time I was pretty sure a smart meter wouldn't work here (no mobile signal) and that seems to be right, as when the chap came to fit the meter he said he'd been told to try and persuade us to have a smart meter instead, but had told his boss that fitting one would be pointless, as it wouldn't be able to connect to the network (he knew our local area well).

 

[vitesse]

I have only needed to charge beyond the 4 hours off peak rate on Go 5 or 6 times in 6 months. We've driven 7000 miles in that time. Not much Supercharging either. For linear demand, the cumulative costs per kWh on the 5th, 6th and 7th hours are 6.8, 8.0 and 8.9 pence calculated with peak rate at 14p. Our breakfast time demand for electricity is very low, barely 2kWh if we don't prewarm the car. That might be an additional 2kWh if the car needs warming. But that's tiny compared to the savings when the car is being charged off peak.