Timed Discharge feeding max power to grid

I have 10.44Kwh of batter storage on a Gen 1 inverter and a 14 panel solar array facing south. My octopus fixed plan has come to an end and despite me trying to go onto economy 7 they have dumped me onto the flexible plan. I have been looking at moving onto their new Smart Flux Tarriff but the peak rate from 1600hrs to 1900hrs is a bit of a worry. I have been trying to set up my system so it will feed from the batteries to cover house usage so I don't pay the peak rate but i can't seem to do it. What I want to do looks possible but it's not working. Here's what I'm trying. I have turned off the eco mode so the batteries don't feed the house when the sun goes in but do charge during the day. I've turned on the timed charge for 0200hrs to 0500hrs and set it to 50%. I have turned on Timed discharge from 1600hrs to 2359hrs to cover the peak period and the evening when useage is heavyest. I have turned off Timed Export so it doesn't feed everything to the grid. What is happening though at 1600hrs when the the Timed Discharge kicks in is the Inverter is just dumping 2.4Kw into the system, the house is using whatever it needs and the rest is being dumped to the Grid. Whilst the export rate at this time of day is a very nice 36.5p per kWh it's not what I'm trying to achieve. Any ideas?

AbbissNG21 for some reason timed discharge doesn't do what it's supposed to. It does indeed export to the grid! Your best bet is Eco & a Timed Charge only, but as the portal/app can only support one timed charge period you'll have to choose the one you want to use. You'd have to use something like Home Assistant or even the Octopus R&D site to use both low rate periods.

Do you not get enough solar at the moment to cover your usage during the day?

@AbbissNG21 I'm looking at this Octopus tariff too and I think I'm in the same boat.

We do have usage during the day so like you I don't want the battery to feed the house between 5am and 4pm and I can't see a way to do that.

However, because the Flux import is cheaper than the day export I do think you'll be best to charge to 100% at the flux rate, that would improve your situation. If you export during the day because your battery is full you'll still be winning and you'll likely have more battery available during the peak time.

I'm also considering putting a timed export in for the last 15/30 mins of the peak, again because the peak export is higher than the day import.

AbbissNG21 I've reread your original post I wonder if Eco mode should be kept turned on? I'm going to run a test tonight with:

• Eco on
• Timed charge 02:10 to 04:50
• Timed discharge 15:59 to 01:59

Will let you know what I see.

Try the scheduler on the Octo R&D portal

I use the overnight charge and am waiting for Octo to sort me onto Flux.
Currently Giv portal is set on ECO (takes over outside scheduler slot) and I do not import any energy other than the night charge and if the battery runs out.
I have a 9.5kWhr and have got through all winter with only the odd bit of import after about 18:00 when the battery has run out after a day with zero solar

I 've tried that and it will start to discharge the batteries while it's still dark at 0450hrs until the sun comes up but if it's a dull day your batteries might be discharged by 1559hrs when you really need them. The timed discharge doesn't do what it says, it puts out 2.4kWh of energy split between the house demand and the grid. Admitidly the feed in at peek for Flux is more than it costs to force charge but I don't want to be in the position that I'm paying the peak rate.

I thought about setting max force charge to 25% (which would get me through peak 3 hours) and charging 0200hrs to 1550hrs which might hold the batteries in a potential 'charging' state even though they had reached the maximum charge from the grid in around an hour, then ending the force charge so they could discharge. With Eco on however this doesn't work as I just had a high load on the system and it took power from the batteries rather than the grid. With Eco turned off and Timed discharge set from 1600hrs to 0200hrs my batteries would be empty in 4 hours due to the dump to grid. If only the dam Timed Discharge worked as advertised!!!!!

GMorris I 've tried that and it will start to discharge the batteries while it's still dark at 0450hrs until the sun comes up but if it's a dull day your batteries might be discharged by 1559hrs when you really need them. The timed discharge doesn't do what it says, it puts out 2.4kWh of energy split between the house demand and the grid. Admitidly the feed in at peek for Flux is more than it costs to force charge but I don't want to be in the position that I'm paying the peak rate.

I thought about setting max force charge to 25% (which would get me through peak 3 hours) and charging 0200hrs to 1550hrs which might hold the batteries in a potential 'charging' state even though they had reached the maximum charge from the grid in around an hour, then ending the force charge so they could discharge. With Eco on however this doesn't work as I just had a high load on the system and it took power from the batteries rather than the grid. With Eco turned off and Timed discharge set from 1600hrs to 0200hrs my batteries would be empty in 4 hours due to the dump to grid. If only the dam Timed Discharge worked as advertised!!!!!

SteveCook Hi Steve, this look more like it. Can you tell me how I access the R&D Portal please.

https://smart-energy.octopushome.net/sign-in

I went here on my laptop, registered and then followed the help info to get it all setup.
Registration was quick, but it took 24/48hrs for all the tabs to appear so it could all pair up

SteveCook Thanks Steve, I'll sign up to that, looks interesting. Could I check though, it looks like your battery is used during the day, am I reading that wrong? The situation I'm trying to find a solution to is not having the battery discharge until 4pm, our house isn't empty during the day so looking at your usage our battery would be mostly depleted by 4pm on a standard winter day.

GMorris
surely your house needed that power for the standby drain so either way you are using it?

@SteveCook I think I understand now and I think that's possible to do in the GivEnergy interface. I think in my case, and it seems odd but:

• Eco On
• Timed charge 02:10 to 15:59

Assume the timed charge is complete within the Flux rate but then blocks off discharge through the day. Any solar would power the house or go to grid.

Then from 16:00, timed charge stops, Eco mode kicks in and that and solar will power the house as best it can until the next timed charge period.

Is that the crux of it?

Thank you.

GMorris Yeah that's what I'm thinking, I'll give it a try tomorrow.

GMorris I know that if you set a timed charge, once the Charge to % is reached, the inverter just "bobbles" along with the SoC dropping a couple of % then charging again, all the time the house is fed from grid. What I don't know is whether, if you set the Charge to % to say 60%, the inverter would charge the battery from excess PV during the day, during the timed charge period. If so, you could power the house and charge to 100% from PV during the day (but not power the house from battery) if your timed charge ran until 16:00. Can you post to let us know if the inverter will charge above the Charge to % from PV during a timed charge period if there is excess PV?

Tim Will do, Eco on and Timed charge set to 25% for 0200 to 1550hrs, I'll let you know how it goes.

GMorris
I have a base load of about 400w (fridge, freezer, NAS box, router, TVs on standby, pond pump etc)
I have battery on charge for the full off peak period, so as soon as peak starts, the battery starts draining.
It gets down to about 70% (Mid fed around 09:00) before the sun starts to help and hopefully covers the house load plus some battery top up.
If am at 100% at 16:00, I can just about make it though to the 00:30 Eco7charge start on battery.

Mid Dec with no sun, battery is flat by 20:00, so I have to pay for 4hrs of peak. I guess I will just have to tolerate this for 3 months a year (half Nov, Dec, Jan, half Feb) unless I buy another battery.

@Tim We have no sun due tomorrow and I want to gauge our evening usage on the battery so I'll slightly tweak what @AbbissNG21 is doing and set our charge to 100% to verify your findings and report back.

SteveCook yeah we've got heating going all day and an office too. You've already got twice the battery we have so I'm just looking to offset the peak with the battery full of flux power and then let the day rate roll as it does now, push as much usage in to flux and take advantage of the better export prices when the sun is out.

GMorris
I think the timed charge should be 02:00 to 05:00 for Flux. That will cancel Ecomode.
I think leave Eco enabled and let that decide what to do outside charge.

I think if you have timed charge on until 15:59 you may end up using grid to charge your battery when the sun is out and at the same time selling excess PV back to the grid at a lower rate - I am not quite sure how that algorithm works.
You may have to play and see.

If Flux has 3 hours when not to use peak import, I think as long as you have about 5kWhr of charge you should easily get though even with electric cooking and then if you have to import it will still be at the standard 33p day rate.

Set timed discharge in Octo R&D or GivEnergy portal from 16:00 to 19:00. I hope that just makes the battery support the house load and NOT export as well (as I would then have to import from19:00 onwards), but until I am switched to Flux, I have not tried.

SteveCook

The Flux numbers for my postcode are below. My thinking is that the import Flux rate is lower than the Day export rate so having the PV send to grid is advantageous if the battery is filled up with lower cost energy. With that in mind I don't want Eco mode thinking it's more Eco to use battery during the day when it's actually more Eco to save it to use during Peak.

Got up this morning and it seems to be working, the batteries are holding thier charge at around 23%, even though I set to 25%, there has been a little bit of use and topping up but by no means is it using the batteries to run the house or they would be empty by now, I use about 10% per hour in the dark. The sun is just starting to come up and the solar is going to the house and cutting down on inport which is great. Looks like it may be a fairly sunny day so hopefully the PV will cover the house, top up the batteries and then at 1600hrs Eco will take over fully and power the house. We shall see.

AbbissNG21

Whatever % I set mine to it always charges to just below, usually -2%

AbbissNG21 good to know. I didn't get to 100% battery in the 3hrs and I've got a very grey day here so it'd be really useful to know if your solar tops up you battery through the day.

GMorris Hi, it does work, it tops up a little occasionally from the grid until the sun comes out but then the Solar tops the battery us as normal, I got to 100% on Thursday and 80% Yesterday. It's a bit of a messy workaround for a function that should work in the app but at least I know I can do it if I want to.

GMorris
Just started thinking about this yesterday. Initial settings failed to do as required. I've now found the R&D labs, so I'll look at that when I get all the tabs up.
This is also my idea. Charge fully at cheap 3 hours. Get battery 100% full at 4pm. Export as much as possible from 4pm-7pm down to about 20%, which should just see me through. (maybe fully discharge as it's cheaper to import after 7pm anyway)
Please let us know if you get success.

AbbissNG21 @GMorris Good to know that the timed charge also enables charge above the Charge to % from surplus PV. For those of you wishing to charge off-peak and then hold the charge until the late afternoon slot for discharge/export, setting the timed charge to start when off-peak starts and end when the late afternoon peak starts but run the house from PV, this does seem to be a good solution.

BarleyRiser the workaround to set timed charge from 2:00 to 15:59 works. I got a good clean cycle in today.

The beauty of the Flux tariff is its simplicity, it’s setup and forget no need to adjust anything dynamically. It’s made our solar immersion heater redundant too.

My plan is to fully charge the battery during Flux, heat water and set appliances during the Flux too. Use any solar during the day and let excess go to export. Deploy the battery at peak for house use. I haven’t tested this yet but I think it’ll be timed export through the peak time, letting the house take what it needs and the rest go to export.

That should even work with an empty house, maximising the arbitrage on the battery power and getting good rates on solar without having to adjust anything.

GMorris makes sense. The only time someone would benefit from more complex charging scheme with Flux is if the system has an export limitation so cannot directly export during peak generation. That capacity would otherwise go unused so is "free" electricity.

Is Flux actually up and running.
I registered an interest and the Octo page says "we will contact you when we roll it out"
2 weeks on and all silent