Pylontech Batteries

[Innes-]

Hi, ive looking at an energy storage system that can operate both on and off grid. I noticed that pylontech seem to have an off grid feature (eps) but im not clear how effective this is for long term off grid use. It seems to be designed for emergency use. Does anyone have any experience of using the eps feature of the pylontech batteries?

 

Also if I attached a large solar array of say 8-10kw to a large capacity battery bank would it be possible to design a system whereby only 4kw of the energy went back in to the grid and the rest was charging the batteries? Alternatively would it be possible to have a system that could be easilly switched between off grid and on grid when more than 4kw was being generated, thus avoiding having to get dno permission for the larger solar array? Thanks

[SteamyTea]

5 minutes ago, Innes- said:

whereby only 4kw of the energy went back in to the grid and the rest was charging the batteries?

I think it would do this anyway because the power will go to the nearest load first.

Check that the batteries can charge at a high level, and as they get fuller, the current they pull gets lower.

and it is kW, not 

7 minutes ago, Innes- said:

kw

 

[A_L]

1 hour ago, Innes- said:

would it be possible to design a system whereby only 4kw of the energy went back in to the grid and the rest was charging the batteries?

 

you want a battery hybrid inverter with export limitation, something like this -

 

https://www.ginlong.com/rhi_inverter1/1952.html

 

 

1 hour ago, Innes- said:

thus avoiding having to get dno permission for the larger solar array?

 

the dno gives permission for the maximum permitted output, the actual size of the array should be irrelevant

[Nickfromwales]

12 hours ago, A_L said:

the dno gives permission for the maximum permitted output, the actual size of the array should be irrelevant

It’s based on the array, and the panic is if the inverter fails and dumps the max to grid.

Been there a load of times and its bloody annoying and crude. 

[Innes-]

Thanks for the replies. The hybrid inverter looks interesting.

 

My questions might make it clear that im not an electrician by any means - just learning as i go ! I was advised by an mcs installer that I cant have any more than 4kW of solar panels on a grid tied system without permission.

 

Does any system/product exist that would protect the grid from loads bigger than 4kW flowing back in to it? 

If not I guess my my choice is between a fully off grid system or getting dno permission for a larger array? 

Edited December 2, 2020 by Innes-

[Nickfromwales]

1 hour ago, Innes- said:

Thanks for the replies. The hybrid inverter looks interesting.

 

My questions might make it clear that im not an electrician by any means - just learning as i go ! I was advised by an mcs installer that I cant have any more than 4kW of solar panels on a grid tied system without permission.

 

Does any system/product exist that would protect the grid from loads bigger than 4kW flowing back in to it? 

If not I guess my my choice is between a fully off grid system or getting dno permission for a larger array? 

Export limitation can be employed to limit the max amount that can go to the grid. Some DNO’s will allow it, others may be particular or refuse. 

[willbish]

27 minutes ago, Nickfromwales said:

Some DNO’s will allow it, others may be particular or refuse. 

@Innes- Western Power were happy to allow my 6kWp system limited to 3.68kW. Which is totally fine with me as my panels are split 50/50 east west, so regardless of the export limitation I would never be able to generate more for than 3.68kW anyway.

The orientation of the panels did not dictate whether WPD would approve or not

 

[Innes-]

Thanks. Will get on to the dno. I am now looking at a fronius inverter with victron inverter charger along with the pylontech which i think will allow me to be off / on grid 

[cmorewood]

Hijacking this thread slightly as its questions about Pylontech batteries.

I'm about to buy 2x US300c batteries to connect to my Victron system. I intend to keep them in my garage which can get down to just below freezing in the winter. They will however be housed in a cabinet.

I noticed that the batteries operate best at 10C. My question is do they generate enough heat to maintain a decent temperature in the cabinet or should I br thinking about building a purpose built housing for them?

I was intending buying a 18U cabinet for 4 or possibly 5 batteries eventually (to keep everything in one place and tidy) but I'm now wondering if, because of the 35kg weight of each battery pack, I should opt for 2 smaller cabinets.

Does anyone have any experience of the temperature and cabinets?

Thanks,

Chris

[Novice]

My battery setup is in an unheated and poorly insulated workshop. I found the heat generated from the batteries soon dissipated and the temp dropped. Since putting a crude cabinet around the batteries (mid December) the average temp is 15°C, workshop temp approximately 5°C. At this time of year I charge the batteries from the grid at night.

Hope this helps.

David

 

[cmorewood]

Thanks for the reply David. Thats a nice setup you have there. It's given me food for thought.

My garage sits at about +5C when the temperature outside is -2C. It's nice to know that the batteries will keep  themselves warm.

 

Chris

[TonyT]

Nice looking set up!