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

Delighted to hear from you, Blastoise186  I have been reading several forums about THTC problems and you seem to have answered many. 

My understanding is that the THTC second (lower rate) meter only supports hot water and storage heating. Therefore car charging will come off the standard rate meter, or can it be connected to the overnight, lower rate meter? 

It surely makes sense to convert the electric supply in my house to that which is being used in new builds particularly as the old 2 meter system is no longer installed. I have no problem with the installation of a smart meter and assume this will allow for cheaper rate EV charging.   

Two years ago you responded to a question on another forum and said it was not rocket science to take out THTC, SSE just didn’t have enough engineers to perform this (I can’t find the original forum). Is this still the case with OVO, or has another problem arisen?

Ah yeah, sorry about that! I was thinking about one of the other tariff types when I wrote that - you are right though. THTC doesn’t have Off-Peak everything like Economy 7 does.

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.

Hey @SunSurg,

Welcome to the OVO Online Community, 

I can see Blastoise has already given some great advice here, just wanted to add we have an FAQ which includes some extra information about THTC meters:

• Complex Multi-Rate Meter & Heating types F.A.Q.

Hi Emmanuelle

Ive read that FAQ, it suggests changes are happening and that OVO will be in touch. However, my conversations with various people suggests that no solution has been found to phase out or develop a new RTS for the THTC meters and the deadline for switching off is fast approaching. I am in email correspondence with Teresa.

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

Ho,hum.

Hey @SunSurg,

I understand your dilemma, it sounds very frustrating.

I wonder if it’s worth doing some research to see if there are any other suppliers actively supporting this meter type currently? Or offering an exchange/solution? 

I’ve been there before when SSE supplied the house. Basically very few suppliers could manage THTC and then many companies folded, as you know. I did think OVO would work out a solution, especially when they have been handed the problem with the takeover from SSE.

I’m about to speak to your solar panel team to see if they have any answers.

Fingers crossed.

OVO has definitely got a solution in the works. :)

Unfortunately, most suppliers - to my knowledge - will choke on a THTC meter setup and only OVO and Scottish Power are currently capable of handling them at all if memory serves. And let’s just say the customer service of Scottish Power often leaves a lot to be desired...

Absolutely, and bear in mind I am with OVO because of a buy out of SSE. I doubt I could go back to SSE even if I wanted to. 
I will wait for the fix by OVO which has to happen in the next 6 months or so. 
meantime, solar panels anyone?

Hey @SunSurg,

Let us know what the team say about solar panels. In the meantime, the website has lots of information about this topic. 

• Solar Photovoltaic (pv) panels: Installation, apps, export payments and ROI - User guide Tutorial

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?

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 

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… 

Battery?  But see my post further down earlier today…

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.

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...!

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?

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:

• Complex Multi-Rate Meter & Heating types F.A.Q.

• THTC / Separate Radio Teleswitch and Meter- Can I get a smart meter?

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...

Might not be applicable but there is the ECO 4 scheme 

https://www.scottishenergygrants.co.uk/solar-panel-grant/

Actually, the last time I looked the Tesla Powerwall is very competitive considering it has ~14kWh of storage and a 3kW inverter and charger built-in (and built by a company with a proven track record for reliable kit.

You are talking about a micro-grid - as to (government) grants, you’d like to think so given the current political significance around energy.  But I guess this specific subject will sort the wheat from the chaff, politically-speaking - ie political/dishonest shenanigans Vs a genuine interest in reducing our dependance on foreign oil/investment money/foreign ownership/control of our basic resources.