How to getthe best out of Octopus Flux

I've turned off my night time charge now that we're getting enough solar - I need to automate it with HA based on solar forecasting - I just haven't found the time to do it yet.
 
Ron-ski said:
It should switch over pretty quick as you're already being paid for export by Octopus.

  1. I set my battery to charge between 2 and 5am, which takes me to about 85% SOC
  2. After 5am house runs off the battery until solar kicks
  3. At around 98% battery charging slows and export starts
  4. Between 16:00 and 19:00 I discharge the battery to no less than 65%
  5. Battery will then see me through to the 2am charging slot.

Once the second battery is on-line which will give me 29kWh of storage, I'll double the charge rate from the grid, and decrease the minimum SOC probably to about 50% as I'd like to keep some in reserve just in case of a power cut.

At the moment I draw 15kWh from the grid every day, and need to export 12 at the day rate to have zero electric bill for the day, so far I've done much better than that.
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Should, but not in all cases. gave up and phoned them today to ask why mine was taking so long to switch - oh you've got two accounts thats strange. Waiting an update from the accounts team. Planning to do similar, but probably only go to about 50% SOC as I lose out on solar generation by 10-20% when the suns at full power through having a 6.3kW array but only a 5kW inverter, however it can cope with 6.5kW DC/AC combined outputs. Like FF I want to get some HA automation set up to adjust this as well as to adjust the rates of discharge so the car doesn't take charge from the battery which it does currently.

Just rechecked my account - on Flux Export now....
 
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Freefaller said:
I've turned off my night time charge now that we're getting enough solar - I need to automate it with HA based on solar forecasting - I just haven't found the time to do it yet.
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I've found solar forecast to be very unreliable, and I just find it so much easier/convenient to charge the battery in the off peak period. Todays solar forecast was supposed to be much better than yesterday, but just looking at the weather showed that was not going to be there case.
 
If your export doesn't get clipped then I'd just charge each night no matter what, easy to manage, no real downsides that I can see.

I did see some people saying that solar gets clipped for them in terms of exporting if the battery is full, and for them I'd say charging less makes sense, but you'd probably always want a minimum charge added.
 
Ron-ski said:
I've found solar forecast to be very unreliable, and I just find it so much easier/convenient to charge the battery in the off peak period. Todays solar forecast was supposed to be much better than yesterday, but just looking at the weather showed that was not going to be there case.
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Fair comment... to be honest I've already made more from export today than I imported this morning between 2-5am!
 
That's the thing, especially with a system that has the capacity, just set the charge, set the peak export, and hopefully it just works with minimal user intervention, and the battery is always charged at the cheap rate, so if the weather is bad at least you're using cheap rate electric.

I'm hoping that in the winter I'll still be at zero or negative cost due being able to peak export enough.
 
I assume your export will be clipped if your bouncing off your inverter limit (anyone in general comment)

I'm going to have a play with my daily generation / exports later and see what the daily costs would have been on flux vs go. With go I am basically paying 75p-£1 a day now. In fact have been all month bar one day when I imported 0.3kwh at 40p a unit
Interested to see what that would have done with Flux. I have exported a little but thats also because the hot water diverter has hoovered up some units on good days.

If it looks plausible then I am going to ask Octopus if I can go back onto Go around September or if thats no longer possible. I suspect they want to move all EVs to intelligent over time.
Also going to ask if Eco 7 is an option as the 7 hour reduced rate window is quite appealing. Even agile may be useful but its hard to predict the coming winter pricing on that since i suspect it will be heavily influenced by the Ukraine situation.
 
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joelk2 said:
is it worth switching to their flux tarrif if i dont have battery storage? im just on one of their flexible tarrifs at the moment
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do you have solar and can you minimise your energy use between 4pm and 7pm? if not then i doubt it.... most people use a lot of energy (cooking tea etc) around then so i imagine you will lose more in the peak hrs than you gain off peak.
 
bigmike20vt said:
do you have solar and can you minimise your energy use between 4pm and 7pm? if not then i doubt it.... most people use a lot of energy (cooking tea etc) around then so i imagine you will lose more in the peak hrs than you gain off peak.
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i have solar, but yeah not likely to reduce much around those times.
 
joelk2 said:
i have solar, but yeah not likely to reduce much around those times.
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what size is your system, average import from the grid daily?? whats your base draw??

When i switched to flux, i looked at my base usage between 4pm and 7pm and looked to see how much it would cost me in that window and how much solar would reduce that base during the spring/summer/autumn and so far for april i am in profit with flux. NO BATTERIES HERE
 
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joelk2 said:
i have solar, but yeah not likely to reduce much around those times.
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you need to look at your solar generation between 4pm and 7pm year round and work out how much you typically import in those times vs how much you export in the day.

no easy answer but my gut feeling - which could be wrong as Welshman disagrees - is unless you have a pretty sizable array then you will lose...... if you DO have a sizeable array then why no battery? get one then the issue is moot ;)
 
bigmike20vt said:
you need to look at your solar generation between 4pm and 7pm year round and work out how much you typically import in those times vs how much you export in the day.

no easy answer but my gut feeling - which could be wrong as Welshman disagrees - is unless you have a pretty sizable array then you will lose...... if you DO have a sizeable array then why no battery? get one then the issue is moot ;)
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it may not be as easy as just get a battery...he may need a new inverter ( if string inverter only) the cost?? etc etc......

But yeh, its well known here that im a very low household energy user ( most energy used between 4pm and 7pm is 600wh's) so around 24p of elec used in that time( approx)
 
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Welshman said:
it may not be as easy as just get a battery...he may need a new inverter ( if string inverter only) the cost?? etc etc......
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Other option is a separate inverter for the battery as others have done, but each install is different, swapping out some inverters is very simple, others more complicated, also could be an old FITS system, so as you say possibly not simple - I doubt it will be a hybrid inverter.
 
Ron-ski said:
Other option is a separate inverter for the battery as others have done, but each install is different, swapping out some inverters is very simple, others more complicated, also could be an old FITS system, so as you say possibly not simple - I doubt it will be a hybrid inverter.
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yeh an AC coupled set-up could work, a little bit costly just to switch to flux though lol....but could help in the long run with not importing as much from the grid.
 
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