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Electricity price predictions

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(@papahuhu)
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Joined: 11 months ago
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@toodles But that’s where your batteries come in, to make up the deficit. You have 2 if I remember correctly, so should be very easy for you. Isn’t that how you work them?

But at 16.00, we’re are outputting 8ish kW, by 19.00 it’s down to 3 ish. We aren’t perfect South, maybe that helps in the afternoon, it’s certainly not a normal distribution. I had always assumed the heavy skewing was largely tree shading, but maybe it’s partially aspect and pitch too. 


This post was modified 4 weeks ago by Papahuhu

   
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Toodles
(@toodles)
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@papahuhu My reply was based on your comment of 6 kW of PV, perhaps you meant availability of a total of PV and battery capacity. In that instance I can output 10 kW from the Tesla system albeit from pure storage capacity or some solar contributing to the 10 kW total (G99). Last year, I gave IOF a try (too early in the year perhaps) but found that with 10 kWh export, my 27 kWh Powerwall set up was depleted after ~2.5 hours whereupon Octopus started to recharge my battery at the peak charge duing the period of greatest demand - thus defeating the object to some extent. I have asked O.E. to inform me if and when IOF returns and may give it a second chance. Recharges, Toodles.


Toodles, heats his home with cold draughts and cooks food with magnets.


   
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(@papahuhu)
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@toodles That’s strange, on IOF mine never imported a bean at peak.I do remember, rather like the machine learning for the homely, it did take a few days to “learn” from the usage data and avoid stupid errors. 

For me, my only objective is to try to maintain annualised zero energy bills for as long as I can. To do so is my transient Sisyphus victory in this chaotic and absurd universe, doesn’t take much to appease my angst!

 



   
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Toodles
(@toodles)
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@papahuhu I found that IOF would attempt to recharge as soon as it reached the preset 20% reserve and I had to intervene by opening the Tesla app and taking action to stop it. 

I wrote to OE and explained and expressed a wish that they investigate and rectify please. Several exchanges of email ensued but no mention about re-writing of the code for the app was forthcoming. I live in hopes that they have rectified the problem now; I did hear that other IOF users experienced the same feature though, Regards, Toodles.


Toodles, heats his home with cold draughts and cooks food with magnets.


   
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(@old_scientist)
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Joined: 2 years ago
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Thanks @papahuhu for your replies.

Posted by: @toodles

@papahuhu My reply was based on your comment of 6 kW of PV, perhaps you meant availability of a total of PV and battery capacity. In that instance I can output 10 kW from the Tesla system albeit from pure storage capacity or some solar contributing to the 10 kW total (G99). Last year, I gave IOF a try (too early in the year perhaps) but found that with 10 kWh export, my 27 kWh Powerwall set up was depleted after ~2.5 hours whereupon Octopus started to recharge my battery at the peak charge duing the period of greatest demand - thus defeating the object to some extent. I have asked O.E. to inform me if and when IOF returns and may give it a second chance. Recharges, Toodles.

I know IOF wasn't perfect, and if the battery was empty before 7pm, it could then start importing again at peak rate (however, given that import and export rates are always the same on IOF, you're not actually losing anything other than conversion losses but it does seem very counter-intuitive). I did see signs of intelligent behaviour though - I'm not sure if it knew my battery couldn't sustain export for the full 3h peak window, so often mine would only partake in 2h:30mins of the export window, often not exporting anything from the battery during 4-4:30pm or 4:30-5pm, and then going flat out from 5-7pm.

Regular Flux is different though, in that you are in control (or maybe the Tesla AI is) rather than Octopus. So if you know your batteries can fully discharge in 2.5h rather than needing the full 3h window, you can just manually set the peak export period as 4:30-7:00pm, holding back export by 30mins to try to ensure your battery is not down to it's reserve until 7pm. In other words, you are not fighting Octopus for control, but are now working with the Tesla AI under Time based control, so it should be easier to control and get the outcome that you want.

@toodles Having more battery capacity (2xPW) allows you to export more at peak rate so there should be more financial benefit (not to mention the clear benefits to the grid by supporting the grid at peak time) to running Flux over a simple self-consumption / SEG export strategy (Cosy import rate is close enough to SEG export rate that I'm essentially just self consuming) as I do with a similar amount of solar and just the one PW3.

I'm going to run some numbers through my own spreadsheet for good, average and bad summer solar days to see what the numbers look like. I'm hoping IOF will become available again which makes the choice easy. I may phone Octopus today to ask if they know when it may become available again, but I doubt the staff manning the phones would know.

 


Samsung 12kW gen6 ASHP with 50L volumiser and all new large radiators. 7.2kWp solar (south facing), Tesla PW3 (13.5kW)
Solar generation completely offsets ASHP usage annually. We no longer burn ~1600L of kerosene annually.


   
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(@old_scientist)
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Posted by: @old_scientist

I'm going to run some numbers through my own spreadsheet for good, average and bad summer solar days to see what the numbers look like. I'm hoping IOF will become available again which makes the choice easy. I may phone Octopus today to ask if they know when it may become available again, but I doubt the staff manning the phones would know.

I've run some very simple numbers through a spreadsheet model assuming 12.5kWh/day usage and that the battery is always full at 4pm, for poor (12.5kWh) average (25kWh) and good (40kWh) solar generation days, and each does work out better on Flux versus Cosy/SEG/ self-consumption & exporting excess.

So I think I will switch to Flux tomorrow and give it a go.

Does anyone else have any experience of Flux with a Tesla PW? How does the Tesla AI handle it in Time Based Control? Does it fully export at 4pm, or does it try to hold back sufficient capacity for the rest of the evening through to 2am? Does it then fully recharge from grid overnight, or does it try to estimate solar production the following day and leave space for the next days solar generation?

I spoke with a helpful guy at Octopus, and he confirmed most tariffs that were temporarily suspended are now available again, but that he had no information on when Intelligent Octopus Flux (IOF) may be available again. He thought the intention was to reinstate it as soon as they are able. He advised to keep checking their website.

 

 


This post was modified 4 weeks ago by Old_Scientist

Samsung 12kW gen6 ASHP with 50L volumiser and all new large radiators. 7.2kWp solar (south facing), Tesla PW3 (13.5kW)
Solar generation completely offsets ASHP usage annually. We no longer burn ~1600L of kerosene annually.


   
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(@papahuhu)
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Joined: 11 months ago
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@old_scientist

I will tell you how mine behaved today, all I did to set it up was input the tariff data. 
My problem is that I get impatient when it doesn’t immediately behave how I want and I start to tinker with the tariffs to exaggerate the buy/sell signal. This time I will sit on my hands for a week to see if it sorts it all out. 

Its 15.00 so far and it has maintained the battery at 100% and only dumped the excess, so far so good…



   
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Toodles
(@toodles)
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@papahuhu Tenterhooks all round! 😉 Toodles.


Toodles, heats his home with cold draughts and cooks food with magnets.


   
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(@papahuhu)
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@toodles Wouldn’t want you to have a sleepless night over it!



   
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Toodles
(@toodles)
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@papahuhu ‘Salright really, I have rested all my tenterhooks in a thick wooly fleece for now. Toodles.


Toodles, heats his home with cold draughts and cooks food with magnets.


   
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(@papahuhu)
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Joined: 11 months ago
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@toodles For years I assumed they were tender hooks although I’ve no idea what I imagined a hook that was tender would be, perhaps one without a barb.



   
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Toodles
(@toodles)
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  • @papahuhu Tenterhooks are used in the process of preparing wool for the production of fabric. The usage to mean ‘in anticipation’ and uneasiness whilst waiting for a result or answer is a more recent usage and, as you say, often mis-written as Tender Hooks. Toodles.

Toodles, heats his home with cold draughts and cooks food with magnets.


   
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