Skip to main content
Rank 2
October 2, 2023
Solved

I've got a THTC meter setup, can I get lower EV charging rates?

  • October 2, 2023
  • 22 replies
  • 467 views

I bought a house in Perthshire a few years ago with THTC installed so have 2 meters. I now have an electric vehicle, but it would appear that I can’t get the low charging rate advertised (and sent by email to me) by OVO to allow overnight charging. At the moment, I have to pay standard rate to charge my car when it would be cheaper to find an on street charger (not easily found in my area). Surely that is not right?

Best answer by Blastoise186

Updated on 28/02/25 by Chris_OVO

 

Update on RTS shutdown:

 

As part of the RTS Project development, we are really happy to share with you our progress:

 

As you may be aware, the RTS signal that instructs some of our meters when to move to the “Off Peak Period”  will be closing down soon and we need to arrange for all of our RTS customers to have a meter exchange so they don’t lose any of their meter functionality.

 

The RTS signal will end for our customers on 30 June 2025. The period between 1 July - 30 September 2025 will then be used to close-down the RTS signal and allow us to manage any unexpected customers impacted.

 

After a very successful pilot, from the 17th June 2024 we will begin writing to our Economy 10 RTS customers to invite them to call us to arrange for their meter exchange. 

 

We are continuing to work at pace to enable the same solution for the majority of our other RTS customers and our aim is to begin writing to these customers in Aug 2024. 

 

We will continue to update you on our progress.

This comment was posted by a forum volunteer.

Unfortunately, THTC is not currently compatible with Smart Meters - this is being worked on - and Charge Anytime requires a Smart Meter in Half-Hourly Mode, not least to act as a way of verifying that the usage is legitimate.

It’s unfortunate, but that’s just how it is I’m afraid. Until you can migrate, your best bet is to try to charge during the Off-Peak hours.

Connecting an EV Charger to the Off-Peak meter is not allowed I’m afraid if you’re on THTC. You might be able to come off of it provided:

  • You’re NOT in a Load Managed Area - your DNO can help you check this
  • You no longer need THTC e.g. your storage heaters are gone

If both conditions are met, you can make that request to OVO and they’ll try to make the arrangements if possible. It’s not impossible to do if the conditions are right, but it’s mostly down to whether the right engineers are around - and you’ll need an electrician to do some re-wiring as well.

 

22 replies

Rank 2
November 14, 2023

I have a house which has 2 electric meters (both original - no gas); one is the day rate meter which runs powers general circuits in the house via one consumer unit and the other meter is the THTC meter which has three outputs, each powering one section of the second consumer unit which is split into; off-peak hot water, night storage heaters, and 24 hour panel heating and towel rail circuits.

I have an EV and would like to take advantage of cheaper night rate charging.

 

I also have a 4kW PV array that is about to go live.

 

I am aware that it is not possible to get a smart meter installed here - for the time-being at least -  due to my location.

Following a recent conversation with OVO helpdesk (instigated by the receipt of my first bill from OVO having taken over from SSE), I am given to understand that the ‘day rate’ meter is now charged at one rate and everything on the THTC meter is charged as another somewhat lower rate.

I am contemplating switching to Octopus and they're Flexible tariff whose day rate is around 30p and night rate, half that.  

 

I can't help wondering why it is I could not simply have my mains board rewired such that everything is run off the THTC meter’s ‘24 hour on’ circuits as then everything would be charged at 15p a unit.  Am I missing something?

 

 

Blastoise186
Super User
Super User
November 14, 2023

I think that would come under fraud I'm afraid. You're not eligible to run ALL your stuff under the 24 hour cheap rate.

Octopus doesn't support THTC Meters either realistically speaking 

Securing energy by zapping security bugs... For that is The Blastoise Way! Remember, I'm just like you - AI Powered Evil Geniuses aren't Staff!
Rank 2
November 14, 2023

Hmmm… I wonder what a jury would have say about that given that I’m being denied that which most electricity customers based on the mainland can get simply by calling up their electricity supplier and requesting a smart meter be fitted?

So, let’s try another tack;  I also happen to have approximately 20kWh of battery and 10kW of inverter set up ostensibly as a backup power supply in the event of (very regular in winter) power cuts. Assuming I powered this from the night storage heating output of the THTC meter, would this be a reasonable compromise, morally speaking, until such time as a smart meter can be fitted? The cable connecting the THTC meter to the night storage portion of the consumer unit appears more than adequate being at least 35mm2 CSA just looking at it.


I don’t really understand why I should be financially penalised, simply because Ovo are unable - or more likely, simply unwilling - to provide me (and obviously thousands of others in the same boat as me) , with an equitable service to everyone else… 

Rank 2
November 14, 2023

I want to install solar panels and feed excess power back into the grid. Again, this seems very difficult with THTC.

Ho,hum.

Battery?  But see my post further down earlier today…

SunSurgAuthor
Rank 2
November 14, 2023

Martin, I went round this buoy several times and have installed solar panels (not by Ovo - too expensive). Energy from the sun is now stored in batteries waiting for my car to be plugged in and if there is excess energy, this is diverted to the hot water tank rather than returned to the grid. Because Ovo can’t work out how much energy is put back into the grid, I can’t generate any claw back.

The light at the end of the tunnel is a smart meter answer for THTC has to be found before April 2024 because the “signal” to these meters is being turned off. Then we should be able to get cheaper EV charging overnight.

I’m not sure Ovo fully understood the problem with THTC when they bought out SSE.

Rank 2
November 15, 2023

 

I’m not sure Ovo fully understood the problem with THTC when they bought out SSE.

It sounds to me lore like they were completely unaware of it - or more likely still, didn’t care.

What do you do when your hot water tank is full of excess PV output and the sun is still shining?  It would be nice to be able to share it with one’s neighbour or something…  I’ve toyed with the idea of putting together a very well insulated (like 200mm of celotex) IBC tank with an electric boiler circulating hot water through it and using that as a large thermal store ideally for underfloor heating but I guess you could use it as a pre-heater for the hot water system, too.  It’d have to be indirect, tho...

I’m not that fussed about selling my spare electricity at this point, tho the idea of a Tesla Energy-like micro-grid set-up would be my ideal and really, this is where the whole planet should be going - preventing all those losses transmitting highly centralised generation over huge distances.  Sharing your excess power over a few hundred metres with your neighbours is a much better solution, paying the National Grid an appropriate fee for the privilege of using their existing network - ‘democratising’ energy generation and storage in the process.  

One can dream...!

SunSurgAuthor
Rank 2
November 15, 2023

Good luck with that dream, Tesla batteries are not cheap.

I did wonder about setting up a field of panels with my nearby neighbours and we all reduce our national demand. Could there be any grants to help with that thought?

Emmanuelle_OVO
Retired Moderator
Retired Moderator
November 15, 2023

Hey @martinwinlow,

 

Unfortunately THTC smart meters are not available yet, I’m not sure what suppliers do provide smart THTC meters currently. 

 

It’s certainly an industry issue, hopefully by April next year these will be available. When we get an update, I'll post on this topic to let you know. 

 

The below topics may have some helpful information:

 

 

 

Renewable Energy? Big Fan.
Firedog
Super User
Super User
November 15, 2023

I did wonder about setting up a field of panels with my nearby neighbours and we all reduce our national demand. Could there be any grants to help with that thought?

 

Have a look at Funding Opportunities | Community Energy England which might be appropriate. 

Noel | I have no official status; I'm just a volunteer who comes here to help other customers. My gear: Aclara SGM 1416-B Electricity-only E7 meter; Chameleon IHD3-PPMID-AAA | It may look as if I know what I’m talking about, but don’t let that fool you. |
Rank 2
November 15, 2023

Have a look at Funding Opportunities | Community Energy England which might be appropriate. 

Regrettably I am way up (and out) on the west coast of Scotland...