Navitron Renewable Energy and Sustainability Forum

Energy/Electricity Storage and Use/Grid Connection => Off-Grid, Batteries & Inverters => Topic started by: M0g on April 06, 2019, 09:58:15 PM



Title: AC Coupled Grid-tied Storage Controller Recommendations
Post by: M0g on April 06, 2019, 09:58:15 PM
I'm looking to add AC coupled battery storage to my system and would be grateful for recommendations. I'm not going down the DC route due to cost. I currently use an average of 5kWh spread over the day, but this is likely to increase to nearer 8kWh in the winter months.

I have an Apollo Gem managing the heating of a 120l indirect vented hot water cylinder and plan to fit larger with either top and bottom immersions or a custom made twin element to heat both the top and bottom of the cylinder.

For batteries, I probably use 12V FLAs with balancers in either 24V/48V strings, controller dependent. I'd like the ability to top-up from E7 and some form of backup to power the fridge and freezer should the grid go down would be good. Weather forecasting would be great, but it's probably over my budget. I'm currently leaning toward the Solar Sofar ME3000S.

Thanks in advance 😊





Title: Re: AC Coupled Grid-tied Storage Controller Recommendations
Post by: Solarchaser on April 20, 2019, 09:55:39 PM
I have the me3000sp,  and rate it.
But be aware, to get the 3kw out of it, you need to have 150ah of batteries connected.
Or 3 pylontech 2.4kwh in my case.

My only complaint about the sofar is anything under 200w of load, its inconsistent in what it does, sometimes it discharges to cover, sometimes it just let's the grid take over.
If your base load is over 200w then it will work well for you.

I've also been looking at the lux system as it offers the chance to parallel with another lux so you could potentially cover 6kw of demand at one time.


Title: Re: AC Coupled Grid-tied Storage Controller Recommendations
Post by: M0g on April 21, 2019, 09:16:31 AM
I have the me3000sp,  and rate it.
But be aware, to get the 3kw out of it, you need to have 150ah of batteries connected.
Or 3 pylontech 2.4kwh in my case.

My only complaint about the sofar is anything under 200w of load, its inconsistent in what it does, sometimes it discharges to cover, sometimes it just let's the grid take over.
If your base load is over 200w then it will work well for you.

I've also been looking at the lux system as it offers the chance to parallel with another lux so you could potentially cover 6kw of demand at one time.

Many thanks for your reply.

My base load is currently sub 200w. Do you know if the firmware can be updated on the ME3000SP? If so, Sofar may fix this issue in the future if they see fit.

With any AC controller, I'll need to figure out a way of assigning priority to it or the Gem.


Title: Re: AC Coupled Grid-tied Storage Controller Recommendations
Post by: nowty on April 21, 2019, 04:47:51 PM
The firmware is updatable but I doubt this will ever be changed as its by design but I think its more like 100w than 200w though.

There is about a 20w overhead in running an inverter so below 100w its not deamed worth running. Even if your baseload is above this there will always be times of the day where the solar almost equals the house load, so the battery discharge drops below 100w and then the inverter cuts out.