Morning everyone,

Do I understand this correctly?

Deye/Sunsynk/Goodwe are full hybrid inverters. Growatt SP5000ES (and others) are off-grid inverters, right?

To my understanding, the full hybrids can "export" PV (and battery) power to non-essential loads, whereas with the off-grid inverters PV and battery will only power the essential loads.

So once batteries are full, the "excess" PV (after supplying essential loads) will be lost and won't power non-essentials (geyser for example).

Is this true?

And are there other big differences between the two?

 

Cheers, Markus

 

Hi @markus_m2

Yep that's true, the reason the sunsynk/deye is so popular is it has all the bells and whistles at a great price. Not everyone has funds for the extra stuff which is why some go for the growatt/axperts. 

On the sunsynk you can connect a self start generator(gas/petrol/diesel), wind generator or a micro inverter which funny enough you would really need if you were going fully offgrid. 

There is another operational difference from what I read around. After the battery is fully charged, even if there is PV available, the Growatt will start using the battery until it drops to a certain percentage. This results in wasting PV power during the day. The Growatt users can comment more on this.

My setup is totally of grid, i.e. I have a change over switch with which I select either my Solar or the grid.
I have no split between essential and non essential, i.e. I manage my power usage within the 5kW Inverter limits. By 11AM in Winter my Battery is fully charged and the Geyser is at the max that the Geyserwise allows. My Geyserwise timer is set to start heating at 10:00 but many a day I manually start heating it at 9 already.
Over the last 6 months I have used less than 10kW per month from the grid.
And yes, the Growatt battery "float" management algorithm has this stupid logic (illogical in my mind) that it uses the battery to power itself once the battery is fully charged, irrespective whether solar is in excess. It slowly discharges at around 0,5A down to 95%. At 94,9% it then goes into charge mode again until full.
On a sunny day when my battery is full between 9 and 10, it will be down to about 95% by around 15:30 to start the top up charge again.

 

Yesterday's and today's Totals so far. This is the typical winter pattern with my setup

 

Edited July 13, 20224 yr by zsde

I've read that all inverters power themselves from the battery when a battery is connected even in utility mode.

13 minutes ago, Buyeye said:

I've read that all inverters power themselves from the battery when a battery is connected even in utility mode.

It's not true for all inverters, for instance Goodwe inverters will not even use the battery unless the load is more than 150W, simply because the efficiency is quite low with such a low load.