Octopus Flux

[SteamyTea]

1 hour ago, ToughButterCup said:

I have five sensors distributed at what I think are sensible places in the house, kitchen, living room, bedroom, mezzanine and wet room.

You can average out the lot, or just pick one or two.

As you want to find the difference between the inside and the outside, you may be better getting an extra two and placing one in the MVHR extract (the pipe that is all the house air), and the other in the MVHR inlet (the outside air).

[S2D2]

On 13/03/2023 at 19:43, Ronski said:

I've now switched over, the import side is sorted, but there seems to be issues for most people with getting the exports setup. I'm going to phone them tomorrow.

 

On 14/03/2023 at 21:48, Nick Thomas said:

Well, that was fast. All switched over :D.

 

So, battery set to charge 2-4:59am and 3-3:59pm; and to force-discharge 6-6:59pm. Heat pump set for DHW 2-3am, and to let the house cool down a bit (not much) 4-7pm.

 

I *think* it also makes sense to bring the house to 20°C between 3-4:59am, in the hopes of coasting until the solar shows up, certainly for March-April and Oct-Nov, but less sure about that. I'm really not keen on being very warm overnight. Might give it a try though.

 

The only other thing to do is add more batteries :3.

 

Any luck with the export for either of you? I was also switched over the same day as applying but export still showing as outgoing. I guess it'll be backdated anyway as it's a linked tariff?

 

Battery happily running the house since 5am on cheap energy, I just need to play around with my ASHP control system to see if I can shift demand into this period too. Turning it off in the peak period worked okay, though the Octopus saver session pushed it to half 7 so the gas kicked in.

[Nick Thomas]

2 hours ago, S2D2 said:

Any luck with the export for either of you?

 

The export was still showing as Outgoing Fixed yesterday; I've just checked now and it's changed over

 

 

I'm expecting both import and export rates will apply from the start of the day I accepted the switchover. Don't care enough to chase it if something else happens though 😅

 

 

 

 

[Nick Thomas]

On 15/03/2023 at 07:39, Ronski said:

My thinking is to fully charge the batteries in the Flux period, then hold the charge to the peak period, so nothing used from batteries until then, then fully discharge the battery during the peak. Anything generated above house load is exported.

 

Interesting, this is a lot simpler than my approach.

 

I feel some reluctance though; I quite like having my own house consume my own solar, but I suppose it doesn't matter too much.

[Dan F]

On 02/03/2023 at 09:46, joth said:

Ah there's the rub. I've somehow* gamed Octopus into putting me on Go import tariff and their Outgoing Fixed (15p/kWh) export rate. So yeah, no, FLUX is not any interest to me while the status quo continues.

 

I'm in a similar situation.  I switched to Octopus Intelligent and they haven't moved me off Agile Outgoing.  Flux is potentially interesting as, while agile export rates were very good last year,  they may not be as good in 2023.

 

The main issue with switching from Intelligent-> Flux is that I'd loose the 10p night-time rate for car-charging.  Paying twice as much to power car, which is one of our main uses of electricity, it's very attractive.

 

On a side note, quite happy I didn't get Powerwall in the end, now that TEP has gone and Powerwall owners are wondering if/how they'll be able to make their Powerwalls export between 4-7pm.

[Ronski]

4 hours ago, S2D2 said:

Any luck with the export for either of you? I was also switched over the same day as applying but export still showing as outgoing. I guess it'll be backdated anyway as it's a linked tariff?

If you are already being paid by Octopus for your export it should be quite quick to switch over, but may need a phone call. If like me your export payments are with another supplier then it will take longer, they told me anything up to six to eight weeks.

 

I'm pretty sure it won't be back dated, someone on another forum said there's wasn't.

[S2D2]

Thanks @Nick Thomas @Ronski, I just wondered if a phone chase was required but I've just checked and the export has gone over now too so all good.

 

I've also gone for two charge periods for the battery, that gives the PV a chance to charge it for effectively 21p/kWh (missed export) rather than the fall back 32p standard rate.

 

I've skipped the force discharge for now as I only have a small battery so it gets used between 7pm and 2am.

[Nick Thomas]

On 16/03/2023 at 15:38, S2D2 said:

I've skipped the force discharge for now as I only have a small battery so it gets used between 7pm and 2am.

 

I guess exporting at 35p/kWh isn't *that* different to importing at 33p 😅

 

Yesterday was a nice sunny day. As a result, I exported lots and managed to break even (I think for the first time since I got the solar panels installed last autumn):

 

 

Summer is going to be great.

 

[SteamyTea]

1 hour ago, Nick Thomas said:

guess exporting at 35p/kWh

With the old Fits, any sale was free from taxation, is this still the case.

Has anyone bothered to check?

[Ronski]

I've not checked, no idea.

[SteamyTea]

7 minutes ago, Ronski said:

I've not checked, no idea.

Just had a quick Google.

Seems that if your generation and consumption are similar, then you are not taxed.

Typical UK law though, vague in the extreme.

So another way to look at it is, it can be taxed.

Edited March 18, 2023 by SteamyTea

[Ronski]

Don't forget you are allowed to earn up to an additional £1000 and not need to declare it.

 

What if Solar export offsets gas consumption?

[SteamyTea]

1 minute ago, Ronski said:

What if Solar export offsets gas consumption?

Who knows.

[Nick Thomas]

Definitely comes under "nice problem to have" 😅.

 

https://www.gov.uk/hmrc-internal-manuals/business-income-manual/bim40520 says

 

> The term ‘significantly exceed’ in (b) above is not defined in Section 782A and should be considered by reference to the particular circumstances. However, in general, a householder who does not intend to generate an amount of electricity more than 20% in excess of their own domestic needs is unlikely to be regarded as intending to significantly exceed the amount of electricity consumed in their own premises.

 

So HMRC gets to decide unless/until it went to court. Of course, you can also just install a heat pump.

[Nickfromwales]

8 hours ago, Ronski said:

 

What if Solar export offsets gas consumption?

What I am looking for tbh.

[Ronski]

10 hours ago, Nickfromwales said:

What I am looking for tbh.

Me two, I plan to fully charge my batteries in the Flux period, then hold the charge until peak period, running off solar or the grid in between, then fully discharge batteries as much as possible in the peak period, then run off what's left and the grid.

 

Any excess generation will be exported. I will have about 28kWh of storage and have an inverter capable of charging/discharging 8kW.

 

So daily electricity costs should be in the negative in the good months and very low in the winter months, net result is it should pay a nice chunk towards my gas bill, hopefully.

[S2D2]

On 18/03/2023 at 11:15, Nick Thomas said:

 

I guess exporting at 35p/kWh isn't *that* different to importing at 33p 😅

 

Yesterday was a nice sunny day. As a result, I exported lots and managed to break even (I think for the first time since I got the solar panels installed last autumn):

 

 

Summer is going to be great.

 

Yes, the rates are essentially symmetric once losses are factored in. That's the main attraction of this tariff I think, the 2-5am charge at 19p is essentially shifted export which you got 21p for some other day (it doesn't matter which, so true seasonal shifting).

 

It's been working perfectly for me so far, the battery ticks along from 5am and lasts until it starts being charged by the solar again. Export covers that initial charge and the very small amount of other import. This includes running the heat pump so the PV is covering ~70% of the heating demand too with the improved weather. Credit to Octopus for this tariff, it really incentivises renewables.

 

As the heating demand reduces the forced discharge will probably become more important, the one thing to avoid is charging up 15:00-16:00 at 32p then having charge left in the battery at 2am meaning you can't charge at 19p. I've had one day where there was a tiny bit left over so may look again at the forced discharge. Though losses are a smidge higher it's still essentially symmetrical to force discharge at 35p then just import at 32p if needed.

[markharro]

As someone who has three phase brought into our building site currently powering our outbuildings on Octopus via a smart meter I've been reading this thread with some interest. Once our house is built over the summer I have just committed to installing about 6.5kw of PV on the roof with the space to increase this to the maximum 11kw in the future. I agonised over a battery but decided against it as they just seem to be incredibly expensive compared to a car battery for example. We will be installing an ASHP and have an electric car although its charging requirements are minimal. So I wondered whether this Flux tariff would work for us without a battery? Or should I reconsider a battery?

[Ronski]

@markharro I would reconsider a battery, and make sure its a suitable size for your usage. In the summer you can maximise export by discharging/exporting in the peak period, and in the winter you can charge in the cheap period and save importing at the higher rates. You really can't compare these sort of batteries to a car battery, they are totally different and store a lot more power. If you want to reduce costs get the PV installed by an MCS registered installer (you need MCS for Flux), but make sure they install a hybrid inverter that you can connect 48v batteries to, then add the batteries later.

 

It can work without a battery, I know some who's gone on it without a battery but their electric usage is very low, and they don't use electric ovens/hobs in the peak period as they cook on gas and BBQ.

Edited April 5, 2023 by Ronski

[S2D2]

A small battery helps to make the most of this tariff, but it is entirely usage dependent as to whether it's financially worthwhile.

 

As an update, my total billed electric cost (excluding standing charges) since switching to Flux 3 weeks ago is £0.78. Not bad at all considering I've also been running the heat pump which has offset around £63 of gas usage over the same period. As heating demand disappears I'm realistically going to have to change my direct debit to ~£0 over the summer as the export will easily cover hot water and standing charges.

 

It's a great summer tariff.

[MikeGrahamT21]

On 15/02/2023 at 17:03, pocster said:

Anyone else looking at this ??

 

 

 

The prices are now available by region, this is mine:

 

[SteamyTea]

1 hour ago, MikeGrahamT21 said:

The prices are now available by region

Do you have a link to the regional prices. Be interesting to see what they are charging in one of the poorest places in the UK.

[Ronski]

You can check rates at https://octopus.energy/smart/flux/ just scroll down the page.

[SteamyTea]

Seems to be the same, almost.

 

Edited April 21, 2023 by SteamyTea

[Dave Jones]

do read this correctly, you are paid 34.9p kw/h if you export during peak rate ?

 

Why not arbitrage it with a battery, charge at cheap export at peak ? 

 

greenenergy uk off peak is 9.52p kw/h which is what i ise to charge up the powerwall if it needs it.