Residential Solar setup in EU

[AdamH]

Hello,

I need your help with setting up my system.

EU-Czech Republic (230V, AC, 50Hz each phase, 3 phase system)

Annual electricity consumption is 11MWh, but now we are heating water with gas, wanna start heating with electricity so 2MWh more in the future and in the future charge EV so another 2-3MWh of power.

3-Phase House (eg. cooking plate + oven uses 3 phases)
Each phase has 16A brakers so ~4kVA per phase

We want to have hybrid system. We can be grid independent for 3/4 of the year.

What we want -

Solar energy will be first used to home appliances, then to charge backup battery, then use it to charge EV, and finally what is left during summer to sell back to grid.

During night, and when we have bad weather, first we want to dump batteries, and after use grid power.

We want to be "independent" during grid blackout.

We can install up to 20kVA of Solar panels to our roof. Split into 4 segments

1) West 11kVA
2) East 3,75kVA
3) South 3kVA
4) Flat 2,25kVA

Because of different orientations and huge distances between solar segments up to 45 meters from south to technical room and 15m west/flat/east to technical room) we would like to use AC coupling with microinverters. We can get pretty good deal on these:

(SunPower 375W Performance 3 + Enphase IQ7A)
Comprar panel solar SunPower 375W Performance 3 con microinversor (tienda-solar.es)

We would like to use 48V LiFePo4 battery architecture with expandable capacity.

What I am not sure about is battery / storage / grid management.

As a battery charger and grid manager we can use for example

Quattro 8000VA, but I need three of them to have 3 phases.

Then every quattro will have its own 48V battery, (for example 3x 8kVA battery pack)
Solar panels would be split to 3 groups of +- same VA of 6,7kVa and every segment would be connected to one quattro.

Is possible to configure quattros to work that they first charge batteries and then the rest is fed to grid?

Do quattros work with Enphase inverters? Can they stop them when the grid is out and batteries are full?

Can this work? Is there another (cheaper) solution?

Thank you very much.
Have a nice day

 

[mrzed001]

Hi from Hungary

What you need is a real hybrid inverter
I do not know how it goes there. Here the utility company has a list of allowed inverters to choose from.



We have the Voltronic Infinisolar 10kW 3 phase hybrid in the list. This is an almost a decade old inverter.
Also called MPP Solar MPI 10kW hybrid (they are the same).
The user manual you can find in the download area

MPP Solar Inc » MPI Hybrid Series

www.mppsolar.com

The other inverter is the Deye 8-10-12 kW hybrid. Here it is not yet in the allowed list, but we are working on it
This is the same as the US top seller Sol-Ark. You can read a lot from it here in the forum.
This inverter even can do AC coupling. So if you have already a grid-tie inverter then you can run it with this in a blackout.

SUN-5/6/8/10/12K-SG04LP3 | 5-12KW | Three Phase | 2 MPPT | Hybrid Inverter | Low Voltage Battery Inverter Company, Supplier | Deye Inverter Technology

NingBo Deye Inverter Technology Co.,Ltd is China SUN-5/6/8/10/12K-SG04LP3 | 5-12KW | Three Phase | 2 MPPT | Hybrid Inverter | Low Voltage Battery inverter company and supplier。 SUN 5/6/8/10/12K-SG is brand new three phase hybrid inverter with low battery voltage 48V, ensuring system saf...

www.deyeinverter.com

Both need 48V battery. Can be lead-acid (if only used for UPS) or LiFePO4 (daily charge and discharge)
And we have a lot of 48V LiFePO4 batteries today
From the very cheap DIY to the rack box and the wall mount versions

 

[brum]

I doubt that you'll be able to mix components from multiple manufacturer and get the working with the priorities that you've listed without custom components.

Check the options to get all the equipment from single manufacturer that can guarantee the functionality that you want. If it was me - I would check SMA. They are AC coupled. I'm not sure if they have hybrid inverter, but consider how often you get power cuts and if this justify the hybrid system.

I started with similar ideas. And for the initial phase I'm going on with just an on-grid inverter. Second phase will add batteries. Running off the grid will be added if needed in future.