Octopus Flux

[Pocster]

Anyone else looking at this ??

 

 

[Pocster]

With a PowerWall it will export when it wants ! - unless excess pv .

As I can dump the SolarEdge when I want ; that’s ok !

Hard to work out if it’s better for me than octopus GO 

[Pocster]

Appears to be a ToU tariff . Great in summer - not so sure in winter …

[MikeGrahamT21]

Interesting, thanks for highlighting.

 

I've just started the application for Octopus Outgoing, to increase my export from 50% deemed at 6p to actual export (near 50%) at 15p.

 

This tarriff would increase that to min 23p, and max 36.5p, with the ability to also charge the battery during the cheaper period through the night in the winter months. Will keep an eye on this as another potential to be better off.

 

I don't have, or plan to have, an electric vehicle so the Go tarriff is not for me anyway

Edited February 16, 2023 by MikeGrahamT21

[S2D2]

Looks good, it removes the need to forecast PV generation when charging battery overnight as the daytime export rate is matched. Time to run some calcs on how much it could save.

[Pocster]

I did read that it’s not fixed pricing I.e depends on wholesale prices . Wether that means it’s fixed for a month or 6 isn’t known yet .

It’s not like TEP in that you control the battery . Tesla are due to update their app soon ( so I’ve been told ) so some adjustment to ToU must be coming .

I haven’t worked out if it’s better for me . My off peak is 7.5p and I almost never draw peak ( benefit of 2 batteries ) .

Edited February 16, 2023 by pocster

[S2D2]

The FAQs say prices change when the standard variable prices change, so presumably it's like Cosy where it's +/-some percent of the standard variable but the numbers didn't come out nicely enough to say it.

 

I've been put off cheap overnight tariffs due to losing the outgoing export rate, so this looks well suited to my setup where the battery isn't large enough to shift everything to overnight charging but could get us through the peak rate window.

[Pocster]

  On 16/02/2023 at 12:50, S2D2 said:

The FAQs say prices change when the standard variable prices change, so presumably it's like Cosy where it's +/-some percent of the standard variable but the numbers didn't come out nicely enough to say it.

 

I've been put off cheap overnight tariffs due to losing the outgoing export rate, so this looks well suited to my setup where the battery isn't large enough to shift everything to overnight charging but could get us through the peak rate window.

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Think we have to wait for more specific detail .

[S2D2]

Early modelling suggests I'd have a 31% higher financial yield from my system per year on this tariff compared to standard variable and outgoing export, a nice little upgrade. Based on 30 min smart meter and PVGIS data, maybe 25% in reality based on the limited data I have so far. Nice to see a PV+Battery targeted tariff at last. Massively system and usage dependent of course, most of the benefit for me comes from the increased export rate.

[MikeGrahamT21]

My export MPAN request has now been accepted, so should be registered in the coming weeks, and then will consider this once its launched

[Pocster]

Don’t think flux will benefit me as I go out my way to use rather than export 

[Nick Thomas]

Well that's very interesting.

 

I've got a battery, but the overall strategy also includes exporting lots in summer to cover the costs of (some of) the electricity I have to import in winter. Being able to export in summer at a higher rate than I import in winter would be pretty awesome.

 

I might need a *bit* more battery to make it work really well, though. As is, a good chunk of my export would go at the ~20p rate instead. Still better than fixed outgoing's 15p, mind.  Avoiding import in the 4-7 period is easy enough, but having enough capacity to do that *and* export at the same time is a bit trickier.

 

 

[Bashers]

interesting - but no fun if you've got a car you need to charge overnight

Shame, ive lots of battery capacity for this, i just wished i worked from home more and did less miles!

[Ronski]

I'm going to be looking at going onto this. Smart meters being replaced Thursday as they stopped working last July, should be ordering the parts for my second 14.5kWh battery tonight, so will have plenty of capacity to dump in the peak periods.

[MikeGrahamT21]

A favourite blog of mine has written about this compared with Go, and created a complex spreadsheet to calculate costs between both tarriffs: https://protonsforbreakfast.wordpress.com/2023/02/23/tariff-calculations-octopus-go-versus-octopus-flux/

[joth]

  On 02/03/2023 at 09:07, MikeGrahamT21 said:

A favourite blog of mine has written about this compared with Go, and created a complex spreadsheet to calculate costs between both tarriffs: https://protonsforbreakfast.wordpress.com/2023/02/23/tariff-calculations-octopus-go-versus-octopus-flux/

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"""

Initially FLUX looks much worse than GO, but the twist is that FLUX offers much higher rates for exporting electricity: 9.4 p/kWh, 22 p/kWh, 36.5 p/kWh for the cheap medium and high rates respectively. These figures should be compared with the miserly 4.1 p/kWh on the GO tariff.

"""

 

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 think this was because I signed up for export only, prior to switching to octopus for import, and the tariff I joined was grandfathered into the new Outgoing Fixed tariff when that came online. The downside is they don't have automatic billing for export payments, I have to email them every 6 months and ask to be manually credited based on meter readings 😕 

 

[Ronski]

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.

[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.

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Strange that they've opened up sign ups, I registered interest weeks ago and have heard nothing!

[Ronski]

  On 14/03/2023 at 07:40, S2D2 said:

Strange that they've opened up sign ups, I registered interest weeks ago and have heard nothing!

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I also registered interest, but didn't get an email, saw it mentioned on another forum. Perhaps they're just trying limit signs to an amount they can manage.

[Nick Thomas]

No email here either. I've just put in the application myself, let's see how it goes.

[Nick Thomas]

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.

[S2D2]

  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.

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How daft they haven't done existing customers that have already submitted their forms and registered interest but oh well, I'll apply tomorrow. Thanks for the update.

[Ronski]

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

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

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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.

 

In the above scenario the size of usable battery becomes limited by your charge/discharge rate, my maximum charge rate in the Flux period is 8kw, so 24kWh for the three hours, same for discharge.

[SteamyTea]

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

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

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Just had a look at my last 3 years worth of temperature data.

The Δ Temp is just the maximum mean temperature minus the minimum mean temperature, there may well be greater extremes i.e. leaving a window open all night in the winter, or not opening a window in the summer, but these would be relatively short term fluctuations i.e. hours.

As you propose to do exactly what my storage heaters do, I don't think there is any real risk of having a house that is way too hot in the mornings and too cold in the evenings.  We can all cope with ±1.5°C without noticing it.

 

[ToughButterCup]

@SteamyTea, I am interested in the detail of how you measure the temperature within your house.

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

In working out the average house temperature would it be sensible just to average all the readings from all of the sensors I have?

 

For me, the end in mind is to look at the average difference between the outside temperature of the house and the inside temperature and look at how that correlates to overall consumption.

 

I ask for your advice because I've become increasingly aware that the devil resides in the detail of how things are calculated and I just wondered what you thought.