Lux ac battery controller

Starfrog

I’d rather just fill the batteries first then sell the export but in winter I don’t get anywhere near enough to power the house and charge the batteries so if I can charge the batteries at a cheap rate at night then use it during day to avoid using grid ? 

Tir3d

Starfrog said:

I’d rather just fill the batteries first then sell the export but in winter I don’t get anywhere near enough to power the house and charge the batteries so if I can charge the batteries at a cheap rate at night then use it during day to avoid using grid ? 

This is exactly what you should do over winter. The downside is that you can't have a great export tariff like Agile Outgoing and also a cheap import tariff like GO or EDF Go Electric. However my saving simply by moving 10kwh of daily use from price capped to overnight discounted rates is in the order of £500 for the winter months even before any solar production. 

Starfrog

How is your setup done eg what tarriffs are you on and would you suggest more batteries than what I currently have (12KWh storage) as I burn through I guess an average of 16kwh during the long dark Scottish highlands winter and have a very low solar production during the mid winter is bad (oct 166, nov 70, Dec 65, Jan 48 feb 138 ) it starts to return to normal in March. I guess the overnight rate would help if I heat my hot water (getting a Sunamp phase change setup that would potentially use 7kwh per day) as my heating and hot water is oil only no gas in highlands. So maybe better to go on an overnight rate for filling batteries and just not filling them as much from grid when it’s summer ? I don’t see any point going on octopus agile as that appears to be just 55p for everything all the time now due to prices 

Solarchaser

Be aware the sunamp only "charges" at 1.8kw, so if you only have 3 hours of go faster it will not give you 7kwh.

If you are on go with 4 hours, grand.
I only mention it as sunamp was a big consideration for me to do heating and hot water, and the main reason I ruled it out was the weedy 1.8kw elements 

Tir3d

Starfrog said:

How is your setup done eg what tarriffs are you on and would you suggest more batteries than what I currently have (12KWh storage) as I burn through I guess an average of 16kwh during the long dark Scottish highlands winter and have a very low solar production during the mid winter is bad (oct 166, nov 70, Dec 65, Jan 48 feb 138 ) it starts to return to normal in March. I guess the overnight rate would help if I heat my hot water (getting a Sunamp phase change setup that would potentially use 7kwh per day) as my heating and hot water is oil only no gas in highlands. So maybe better to go on an overnight rate for filling batteries and just not filling them as much from grid when it’s summer ? I don’t see any point going on octopus agile as that appears to be just 55p for everything all the time now due to prices 

So I have 6kw of solar, on a Lux 5kw hybrid inverter, with 10.5kwh of pylontech battery storage.

May - September 2022: Octopus Agile (import) and Outgoing Agile. The import part only made sense when the traiff was capped at 35p and the standing charge was at 21p. The low standing charge was awesome. Since the recent increase to both there's now no sense in getting Octopus Agile versus a regular price capped tariff which is cheaper and you can also have with Outgoing Agile. I am averaging 22p kwh for export at the moment. 

October - April 2022: Octopus GO and Octopus SEG tariff for Outgoing at 4.1p kwh for export. Full charge of the battery at night and also "Charge Priority" set on the inverter which means that my house load will pull from the grid not my batteries during the cheap hours. 

Since you can't have both GO and Outgoing Agile at the same time sadly. https://octopus.energy/blog/outgoing/

Some things to think about:
-Battery capacity, how much load can you shift to cheap rate? Do the maths but given your setup I'm sure GO will save you money.
-Battery charge rate, I can charge my batteries at max 3.6kw on the Lux so in Octopus' four hour charge window I can charge no more than 14.4kwh of capacity, which is not an issue for me.
-HW immersion on a timer to come on during cheap rate. GO rate is cheaper per kwh than gas is, for sure it will be versus oil.
-I don't have a HW diverter (Eddi or similar) as I did the maths and it wouldn't pay for itself for a very long time. 
-Likely solar input during the day, hopefully helping you need less battery storage and less charging at night. 
-Main fuse on the house, I have 100amp, some people have 60/80amp. 60 amp could easily be strained by battery charging, immersion, EV, dishwasher etc etc.
-Do you have an EV? Octopus do require you to have or have ordered an EV to be on GO. I believe that Bulb don't so that could be the workaround.

I hope this helps.

newbuilder

@Tir3d
quick question, I toooperate off peak very much like you and now we have a second ev I have a zappi installed. Still trying to load shift within the go faster period to keep the 10” amp fuse healthy but noted last night that the ac voltage dropped below acceptable tolerances and zappi entered delay mode due to the house going out with tolerances. Have you experienced this? Do I have to live with it or is this something the electricity network distributor should know about? 

Tir3d

@newbuilder do you have an inverter that shows you the frequency versus time so you can check that the Zappi isn’t faulty? I’ve read elsewhere about Zappis doing what you describe.

This is beyond my expertise but I believe that you should be able draw current up to your cut-out fuse rating without issue. You’ll share that cable with neighbours.

newbuilder

Yes the voltage dip is measured from the luxpower 
the improvement may have happened due to the zappi disconnecting for “up to 10 mins” as part of the new mechanisms to protect grid and device. 

Starfrog

Tir3d said:

Starfrog said:

How is your setup done eg what tarriffs are you on and would you suggest more batteries than what I currently have (12KWh storage) as I burn through I guess an average of 16kwh during the long dark Scottish highlands winter and have a very low solar production during the mid winter is bad (oct 166, nov 70, Dec 65, Jan 48 feb 138 ) it starts to return to normal in March. I guess the overnight rate would help if I heat my hot water (getting a Sunamp phase change setup that would potentially use 7kwh per day) as my heating and hot water is oil only no gas in highlands. So maybe better to go on an overnight rate for filling batteries and just not filling them as much from grid when it’s summer ? I don’t see any point going on octopus agile as that appears to be just 55p for everything all the time now due to prices 

So I have 6kw of solar, on a Lux 5kw hybrid inverter, with 10.5kwh of pylontech battery storage. 

Is the lux 5kw inverter good due to it being able to take more solar power from the array ? My 3.6 lux hybrid always clips at 3.5kw but I have 5.42kw solar array. It would be good to maximise my ability to charge my batteries quicker but it seems that is restricted to around 3.6kw so maybe no benefit for me other than I should have good overcapacity during a 25year period 

May - September 2022: Octopus Agile (import) and Outgoing Agile. The import part only made sense when the traiff was capped at 35p and the standing charge was at 21p. The low standing charge was awesome. Since the recent increase to both there's now no sense in getting Octopus Agile versus a regular price capped tariff which is cheaper and you can also have with Outgoing Agile. I am averaging 22p kwh for export at the moment. 

I’m with octopus and currently on fixed loyalty at rate of 26.61/kWH and standing charge of 26.09. Which I usually just calculate as im paying around 31p per kWh all in. That is fixed till March then I’ll need to see what the best tariff to go on is. On my very best days of production the most i have had in the two years is 34kW of solar production for the day on average i guess in summer days it’s around the 20 and above (the Far northern highlands isn’t the best for solar but its good enough to save me money)

October - April 2022: Octopus GO and Octopus SEG tariff for Outgoing at 4.1p kwh for export. Full charge of the battery at night and also "Charge Priority" set on the inverter which means that my house load will pull from the grid not my batteries during the cheap hours. 

Since you can't have both GO and Outgoing Agile at the same time sadly. https://octopus.energy/blog/outgoing/

Some things to think about:
-Battery capacity, how much load can you shift to cheap rate? Do the maths but given your setup I'm sure GO will save you money.  

My preference would be to always use all my solar production which obviously would maximise any additional cost coming from the grid. That is best option but as we both know not the most practical due to batteries either being full due to good solar the previous day or power not being used. I think having a Sunamp installed will help take any excess solar (would i need an Eddi for that ?) to heat my hot water without having to get it from the grid at prime time rates (i would use either the solar or the battery or cheap rate go/night rate etc). Currently all showers in the house are via an electric shower which pulls just under 9kWh so even with maximum solar production and full batteries I still draw from the grid to provide the energy for the shower. Sunamp will allow me to just use a normal hot water shower and mixer thus reducing the need to use the grid at all for the showers. 

-Battery charge rate, I can charge my batteries at max 3.6kw on the Lux so in Octopus' four hour charge window I can charge no more than 14.4kwh of capacity, which is not an issue for me.

I think i might get one more pylontech 5kWh battery which will give me 17kWh of storage that should allow me to meet virtually all my requirements on normal days and minimise grid draw. Obviously in winter getting a good cheap rate option like go or something similar would help the period when solar production is rubbish. 

-HW immersion on a timer to come on during cheap rate. GO rate is cheaper per kwh than gas is, for sure it will be versus oil.
-I don't have a HW diverter (Eddi or similar) as I did the maths and it wouldn't pay for itself for a very long time. 

I think the Sunamp takes about 7`kWh for a 210 ltr tank of hot water ? I would charge with excess solar and or in evening at a cheap rate tariff. I think a Sunamp is good for keeping the heat available until its called for so if i only use one shower I potentially only need to feed enough to cover that portion unlike traditional water tanks that you more or less have to heat the entire thing and then keep boosting it to keep the heat 

-Likely solar input during the day, hopefully helping you need less battery storage and less charging at night. 
-Main fuse on the house, I have 100amp, some people have 60/80amp. 60 amp could easily be strained by battery charging, immersion, EV, dishwasher etc etc.

I have a 60amp fuse but I intend to upgrade all the electrics in the house at somepoint. I have someone coming round to fit my Smart meter next Wednesday (after a two year wait and asking virtually every day for one !) I maybe should ask them if they could just swap the fuse out to a larger capacity 100amp maybe ? Is it that easy to just swap the main fuse out like that ? Im not an electrician and pretty sure there are lots of things to consider. 

-Do you have an EV? Octopus do require you to have or have ordered an EV to be on GO. I believe that Bulb don't so that could be the workaround.

I dont have an EV and to be honest wont get one until the next change of car so that could be 4 years at least in my mind (my car is fully paid for so its just maintenance cost now so dont want to start with a new car cost). The other issue is where i live is so remote that even using a hybrid with 30 miles on it would mean id only get to the next slightly larger town and still need to charge it again to get back (74 miles return journey) and then if i wanted to go to the next larger town its really is a 200 mile return trip to Inverness. So timings and finding suitable chargers are something id need to keep considering. 

I hope this helps.

Very helpful and thank you hopefully you dont mind all the questions  

See my italics responses and questions much appreciated  

Heedtheadvice

@newbuilder

Your voltage, as measured, is overall on the low side. Inform your DNO to investigate and correct. You might look at a second concurrent set of readings to give an indication it is not a property issue first such as your Zappi and the lux for the same time period....