Solar with Battery - Winter alternatives to Octopus Flux ?

Parrinaf

Hello to all

I've been lurking in this forum for some time - just joined up as I wish to post a query.

To set the scene ... (I'll see if I can add this to my signature later - currently restricted as a "newbie")

Setup - 16 x 410w Canadian Solar, all South Facing in NW England  + SE 6000H HD Wave Inverter & Optimisers, plus Tesla PW2 functional from February this year.
I also have a Mixergy cylinder with MyEnergy Eddi and WB System Boiler operating in weather compensation mode with smart TVR. Single phase 100A grid supply

My Solar PV system fully functional since February - had a daily peak generation in May/June of 50 Kw Hrs. Total generation for year to date is 6 MWHr (May - 1.15 MWhr, June 1.11 MWhr) unfortunately somewhat down hill since then  ...

I'm with Octopus Energy currently on their Flux import/export tariff :-) I like Octopus and would prefer to stay with them (seem to be efficient and dynamic)

Daily average home consumption is approximately 10KWhr (probably less)

Electricity usage (Feb -> Sep inclusive to date)

Export  2769 KWhr (£676.42 received)

Import  345 KWhr

Have made no payments to Octopus since April and account is currently just under £500 in credit.

Having played around with Home Assistant (new to me) I have been able to successfully set it up such that I can schedule overnight changes to my Tesla PW2 configuration thus

Self Powered Mode 05:00 -> 02:00 (Backup Reserve 30%)

Time Based Mode 02:00 -> 05:00 (Backup Reserve 100%)

So basically at 02:00 every day battery fully grid charges at 5KW to 100% and then sits at 100% whilst house runs from grid until 05:00 at which point it reverts to using the battery and then hopefully solar PV. My estimation is my battery will cover a full day home consumption (may be pushing it a bit mid Winter - I suppose I could reduce my backup reserve level) Any surplus PV generation is pushed back to grid, but I do not export from my PW2.

My current flux rates (appreciate these will vary depending on where you are in the UK) are

Import
02:00 -> 05:00  18.7p KWhr
05:00 -> 16:00  31.1p KWhr
16:00 -> 19:00  43.5p KWhr

Export - timing as above
7.7p
20.1p
32.5p  

Daily standing charge 60.1p

Whilst there will be a DC/AC conversion overhead, for now I have been happy to assume that my 18.7p overnight import cost is covered by solar 20.1p export credit, so no need to mess around trying to guesstimate solar generation and energy needs for the future days.

Obviously with an eye to the impending Autumn and a lack of solar generation, I am keen to see how I might import electricity overnight at further reduced cost, before reverting to Flux (or its successor) come the spring.

The Octopus Go tariff appealed but my Tesla is bolted to my garage wall (rather than sitting on four wheels) so I suspect that it is a non starter. Just wondering if anyone else, in a similar scenario, has spotted any alternatives ?

Alnat1

I've been on Flux over summer and quite happy with the tariff but it won't work well for me over winter. A few days ago I changed to Agile and Outgoing Fixed at 15p.

I'm happy to accept the lower rate for export as there won't be that much over winter. With Agile you tend to get cheaper slots overnight (often in the Flux 2-5am times) but also some early afternoon, so I can top up my small battery again if needed before we hit peak prices.

I've topped up this afternoon at 5pkWh and now the rain's gone, suns out and I'm exporting at 15pkWh. OK, prices might not always be so good but I was on the same Agile/Fixed last winter before Flux existed and made it work. Similar situation to you, summer exports will hopefully cover a lot of the winter's bills.

Agile prices tonight are actually going negative at times, it's all good fun if you like playing with your PV system and are happy to time-shift using appliances.

jneill

Eco 7 has a lower import rate (16.39p south east england) than Flux (18.54p).
  
For exports, Octopus offers the Outgoing Fixed tariff (-15p) with Eco 7 for those occasional sunny winter days.

Agile looks v interesting but I'm not quite convinced yet, can be V cheap, but usually isn't...

QrizB

jneill said:

 But I don't know if Octopus offers an export tariff with Eco 7 for those occasional sunny winter days. I have asked, earlier today.

I'm pretty sure you can have Outgoing Fixed or Outgoing Agile together with Flexible E7 or Fixed E7.

pensionpawn

jneill said:

Eco 7 has a lower import rate (16.39p south east england) than Flux (18.54p).
  
For exports, Octopus offers the Outgoing Fixed tariff (-15p) with Eco 7 for those occasional sunny winter days.

Agile looks v interesting but I'm not quite convinced yet, can be V cheap, but usually isn't...

I've just updated my spreadsheet to compare my net elec import / export on Flux with outgoing fixed and fixed 27.5p import. So far this month only 16th / 17th and no doubt today is worse on Flux. No doubt this will change significantly as we enter GMT, however I plan to stay on Flux unless my spreadsheet indicates I'm ploughing through the Flux cash buffer / generation FiT at a much steeper rate than anticipated.

ecraig

I ran my historical import numbers for the period of November to march through and determined that:
with agiles historical charges that period would have cost me £284
with flux £281
economy7 is £223.
I modelled my usage charging my battery at 3kwh, so 1.5 every 3 mins. 

I also observed that if I used all of the plunge price opportunities fully I would have saved just £6 over that period. 

For me, I’ll be returning to E7 very soon. 

Magnitio

Just switched to Agile from Flux for the winter as I don't mind changing charge settings based on prices and weather.

When I was last on Agile, the ceiling was 35p/kWh, but that has increased to 100p/kWh. Hopefully we won't have gas supply issues in the middle of a cold spell when there is no wind.

Jonboy1889

Did you guys have to change both manually? Did the switch Flux to Agile import easily, but the export change seems to require all the original MPAN etc in the online form. It still says Flux export on my account. Have messaged octopus 

Magnitio

Jonboy1889 said:

Did you guys have to change both manually? Did the switch Flux to Agile import easily, but the export change seems to require all the original MPAN etc in the online form. It still says Flux export on my account. Have messaged octopus 

Octopus don't make life easy at times. I had to enter all of that info, which they have had twice before. They still haven't moved me from Flux export, but I'm not complaining as it is better than the fixed 15p/kWh.

Jonboy1889

Magnitio said:

Jonboy1889 said:

Did you guys have to change both manually? Did the switch Flux to Agile import easily, but the export change seems to require all the original MPAN etc in the online form. It still says Flux export on my account. Have messaged octopus 

Octopus don't make life easy at times. I had to enter all of that info, which they have had twice before. They still haven't moved me from Flux export, but I'm not complaining as it is better than the fixed 15p/kWh.

Ha ha yeah exactly the same as me!! My guess is they will retrospectively change the rate to 15p from the import switch date. Altho when I moved to tracker Gas, they accidentally moved me to tracker electric too - and charged me tracker rates until they had moved me back to Flux.

really don’t understand why you have to put everything in again, surely they have it on record!!

Magnitio

Jonboy1889 said:

Magnitio said:

Jonboy1889 said:

Did you guys have to change both manually? Did the switch Flux to Agile import easily, but the export change seems to require all the original MPAN etc in the online form. It still says Flux export on my account. Have messaged octopus 

Octopus don't make life easy at times. I had to enter all of that info, which they have had twice before. They still haven't moved me from Flux export, but I'm not complaining as it is better than the fixed 15p/kWh.

Ha ha yeah exactly the same as me!! My guess is they will retrospectively change the rate to 15p from the import switch date. Altho when I moved to tracker Gas, they accidentally moved me to tracker electric too - and charged me tracker rates until they had moved me back to Flux.

really don’t understand why you have to put everything in again, surely they have it on record!!

They have now moved me onto Fixed export and applied it retrospectively, which is a shame.