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Can anyone recommend an AC coupled inverter for the UK please?

MisterB1959

Solar Enthusiast
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Oct 22, 2022
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Good afternoon (UK time), i am in the process of putting together a plan for home battery storage and building my own batter bank using EVE cells.

what i need advice on please is which decent AC coupled inverter i should be looking at? i already have a 4kw solar system installed, from which i receive FIT payments, so cannot alter/ammend the current setup without affecting those payments - which obviously i dont want to do.

i would like to add additional solar to this 'new' inverter, to supplement power use and battery top up especially in the winter months - but at the moment that isnt a necessity as i want to increase battery storage up to @27kw on my next stage.

thanks for reading
 
How many kW are you looking for?

Victron and SMA have a variety of sizes and should be available, both are high quality. Outback, Schneider, and Magnum are also good brands although not as many sizes and may not be readily available in the UK.

If your existing inverter is oldish, you might be beyond the warranty and one of the new hybrid inverters might serve you better. Hope that's of some help!
 
Charging 27kw in Uk winter:confused:. How many panels are you planning?
i understand your point, but i intend to take advantage of off peak electricity to charge as much as i can during the winter months. my rates are approx 7p during off peak 0030 - 0430 and 41p from 0430 to 0030.

with regards to winter solar gain, my thought process is that if i can reduce my dependency on grid bought power for 8 months of the year, then it will offset the costs incurred during the 'winter' months when little or no solar is produced, so instead of making hay when the sun shines i will be cutting my costs when it shines and saving the money i would have spent for 'a rainy day'.

so i need to be able to harvest as much as i can in the time period i have available - if i can store 20kw at 7p and then use it during the period it would cost 41p its a big saving - £1.40 as opposed to £8.20 ...... so if i save £6 per day for 120 days it equates to £720 saving per year PLUS 240 days when even if only save £2 per day, that equates to another £480 per year .....

of course my thought process is only that, its just a guestimate ......
 
sunsynk (aka deye/sol-ark).
couple your currect system to the aux/smartport and you're golden
thanks, i will take a look at that. As i want to take advantage of off peak electricity to charge the batteries, i need to be able to charge them within a 4 hour period, can you or anyone advise on an inverter can deliver a high charge rate (if thats a sensible thing to do?)
 
How many kW are you looking for?

Victron and SMA have a variety of sizes and should be available, both are high quality. Outback, Schneider, and Magnum are also good brands although not as many sizes and may not be readily available in the UK.

If your existing inverter is oldish, you might be beyond the warranty and one of the new hybrid inverters might serve you better. Hope that's of some help!
thanks, i want to avoid 'changing' my current solar set up - i know i am allowed to change my current inverter if it becomes faulty without impacting on FIT (feed in tariff) payments and that will no doubt happen eventually but i am trying to keep the systems separate at the moment.

thanks for the suggestions of suitable inverters. i am initially going for 13kw of batteries and if the systems performs as i hope, then i will add additional batteries next year - i will be building my own batteries using 16 x lifepo EVE cells 280K
 
thanks, i will take a look at that. As i want to take advantage of off peak electricity to charge the batteries, i need to be able to charge them within a 4 hour period, can you or anyone advise on an inverter can deliver a high charge rate (if thats a sensible thing to do?)
the 8 KW version of the sunsynk can do for a Battery charger – 190A
i would call that a pretty steep charging, and it may be more than your batteries can handle
 
the 8 KW version of the sunsynk can do for a Battery charger – 190A
i would call that a pretty steep charging, and it may be more than your batteries can handle
thanks, i am looking at a Sofar ME3000 at the moment - on the basis that i know someone who has done what i intend doing and it seems to work ok. once set up, i can always change/improve and pass the inverter on to one of my children to help them ...
 
i understand your point, but i intend to take advantage of off peak electricity to charge as much as i can during the winter months. my rates are approx 7p during off peak 0030 - 0430 and 41p from 0430 to 0030.

with regards to winter solar gain, my thought process is that if i can reduce my dependency on grid bought power for 8 months of the year, then it will offset the costs incurred during the 'winter' months when little or no solar is produced, so instead of making hay when the sun shines i will be cutting my costs when it shines and saving the money i would have spent for 'a rainy day'.

so i need to be able to harvest as much as i can in the time period i have available - if i can store 20kw at 7p and then use it during the period it would cost 41p its a big saving - £1.40 as opposed to £8.20 ...... so if i save £6 per day for 120 days it equates to £720 saving per year PLUS 240 days when even if only save £2 per day, that equates to another £480 per year .....

of course my thought process is only that, its just a guestimate ......
thanks, i am looking at a Sofar ME3000 at the moment - on the basis that i know someone who has done what i intend doing and it seems to work ok. once set up, i can always change/improve and pass the inverter on to one of my children to help them ...
Even with 13kw battery rather than 27k, that ME3000 will be maxxed out to just about charge the batteries in 4 hours. I think you might need a more powerful inverter/charger if you're going for that much storage.
 
Even with 13kw battery rather than 27k, that ME3000 will be maxxed out to just about charge the batteries in 4 hours. I think you might need a more powerful inverter/charger if you're going for that much storage.
thanks, i did think similar thoughts but i need to start somewhere to try it out. there is a good second hand market but my intent is that once i have got everything up and running with the Sofar and 13kw of batteries and understand how it all works, then i can pass the Sofar to my daughter and invest in a bigger inverter and additional batteries.
 
i understand your point, but i intend to take advantage of off peak electricity to charge as much as i can during the winter months. my rates are approx 7p during off peak 0030 - 0430 and 41p from 0430 to 0030.

with regards to winter solar gain, my thought process is that if i can reduce my dependency on grid bought power for 8 months of the year, then it will offset the costs incurred during the 'winter' months when little or no solar is produced, so instead of making hay when the sun shines i will be cutting my costs when it shines and saving the money i would have spent for 'a rainy day'.

so i need to be able to harvest as much as i can in the time period i have available - if i can store 20kw at 7p and then use it during the period it would cost 41p its a big saving - £1.40 as opposed to £8.20 ...... so if i save £6 per day for 120 days it equates to £720 saving per year PLUS 240 days when even if only save £2 per day, that equates to another £480 per year .....

of course my thought process is only that, its just a guestimate ......

When estimating costs and savings don't forget to factor in the losses on converting from AC to DC and then DC to AC.
Depending on how efficient your charger / inverter is, it could be 10 or 20%, but even then, on your day and night rates you'll still be making a saving :)
 
When estimating costs and savings don't forget to factor in the losses on converting from AC to DC and then DC to AC.
Depending on how efficient your charger / inverter is, it could be 10 or 20%, but even then, on your day and night rates you'll still be making a saving :)
i certainly dont expect to reduce my bills completely, but if i can get my investment back in less than 5 years then i will consider it to be a massive success ...... my solar paid for itself in around 6 years and is now 'all profit', thanks to the Feed In Tariff scheme, of which i have around 16 years left of payments, then i am pretty sure there will still be a market for any energy i produce however inefficient it may be deemed to be.
 
I have 8kw Deye. I thought it would be able to charge at 190A (and planned my wires accordingly), but the most I can get out of it is 133-134 Amps. Fortunately this is just enough to charge my 28kWh pack within the 4 hours of cheap night tariff. However I don't need to fully charge the battery as the capacity covers two days of my average consumption. So it worked out nicely in the end.
Perhaps next time I'd go for a 12kW inverter hoping that it would turn on the fans less or not at all. This one does turn on the fans at night or during high loads. The fans are roughly as loud as a microwave, and from the pantry they are almost inaudible. But the fans can be the weakest point for longevity.
 
I have 8kw Deye. I thought it would be able to charge at 190A (and planned my wires accordingly), but the most I can get out of it is 133-134 Amps. Fortunately this is just enough to charge my 28kWh pack within the 4 hours of cheap night tariff. However I don't need to fully charge the battery as the capacity covers two days of my average consumption. So it worked out nicely in the end.
Perhaps next time I'd go for a 12kW inverter hoping that it would turn on the fans less or not at all. This one does turn on the fans at night or during high loads. The fans are roughly as loud as a microwave, and from the pantry they are almost inaudible. But the fans can be the weakest point for longevity.

did you have to have the main incoming fuse uprated? i thought the max was 100A and most are 60A?
 
very interested in this topic. I currently have a grid tied 4kw system on FIT. I am making my own powerwall, starting with 5kw and adding to it. How do you propose to use the battery bank during daylight hours and keep the FIT meter 'fed/going/reading'.
I was thinking of using extra panels to charge my 'off grid' project and using a changeover switch at dusk dawn to run the house. Any bright ideas welcome. thanks.
 
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