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I'm meeting my installer this weekend, and we're going to choose products for my install, but I have a couple of questions...

I've pretty much decided I want the Sunsynk inverter... probably the 5kW (maybe the 8 depending on price) but where I fall down is on batteries.... We'll go over his thoughts and recommendations, but I'm keen on hearing experienced points of view...

Hubble seem to talk nicely to the inverter, but I'm concerned that 5kWh might not be big enough.
SolarMD? My installer rates them highly (comes in a 7.4kWh)
Sunsynk? The Ellies site shows that they have their "own" batteries?
Pylontech? Also rated highly, but I've been reading there might be "problems"?

Any other options people can put their name behind?

 

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46 minutes ago, bobmabena said:

recommendations

based on your location I would consider adding some wind turbine or two, which may reduce the battery capacity requirements some...

As for which supplier, a tough nut, they all use some LiFePO4 cells made in outer Mongolia or thereabouts and none will presumably give you the honest low down on the actual cells used. What ideally should the maximum sustained discharge rate be for the cells, for instance, in order to still get maybe 5000 cycles out of them... etc.

I will be looking at bringing in some LTO cells in the future and make up my own battery bank, but 1st will have to find a BMS that fits the bill and which will use the CAN bus to talk to the Sunsynk...

As for not being sure whether 5kWh are enough, meet boetie, meet, there's nothing like knowing what your consumption is day by day and period by period... here we use around 7kWh after dark and before Sol adds its photons to the mix, we have, at time, height of summer, used up to 12kWh even, but presumably that was when thunder/lightning and loads of water vapor were obscuring Sol for at least part of the day...

Here we don't have regular wind, so a wind charger won't help... and constructing some sort of water wheel platform to tie off in the river and use this, isn't allowed, besides, running 1.5km's worth of power lines over some farmers irrigation lands would be a challenge to say the least...

So, sorry about not really answering the question about whose battery pack to buy, but in terms of how many kWh's to cater for, you should probably leave 20% in the bank at least, so if your consumption measures out at, let's say 8kWh for the night, then you should probably look at 10kWh capacity and this usually would be made up by more than one battery, which in itself makes sense, since very few LiFePO4's are specced at 1C and I'd be dubious about the ones that are and would not want to run them at more than 0.5C, for peace of mind/longevity which means 2 X 5kWh batteries would be what you'd need in this example, assuming the batteries are specced at 0.5C or more, this assumes you actually peak at this sort of consumption, here I can't recall seeing much more than 3.75kW peak utilisation and mostly a maximum of 2.8kW and overnight, when the batteries, presumably would be needed  usually less than 2kW peak....

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i have a 5 kW Sunsynk and Pylontech 4.8 kWh batteries, during summer I was generating just over 20 kWh per day with 4.2 kWp of panels, i run a geyser every day, washing machine/dishwasher/tumble dryer/aircon/pool pump and also a microwave and kettle ( but they only run for a short time, here and there), If there was not enough solar and reached the 0.5 C disharge rate for the Pylontech batteries, the system just drew from the grid for a short period. This is based on judicious time management of your loads.

 with winter setting in ( Cape Town ) we don't usually get the solar pv production, so i draw more from the grid. My suggestion is to start with one 5 kWh battery and add another one down the road ( can add lithium batteries at any time to a current stack ), at this stage Eskom is cheaper than batteries, but you need something for back up when there is no grid and no solar production

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We've generally been really pleased with the Revov batteries. I personally haven't used them with a Sunsynk but the manufacturer says they communicate very nicely. Revov is supported by Solar Assistant (not the R8 or C8 yet but soon) and ICC (Sunsynk to be added soon apparently). You can start with the B100 or R100 5Kwh and add as needed. They are rated for 100% DOD in their stated capacities so you don't need to get out the calculator to work out the usable energy😋

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@bobmabena Hubble batteries are Great an rated at 1c also they are compatible with the RIOt which gives you all the monitoring info you can possibly need you can parallel 15 units and their after sales support is pretty good I would avoid Pylontech too many issues and warrranty repairs and returns a major headache Revov I don't have a lot of experience with but they are mostly secondhand EV batteries that have already been cycled and have lost 20% of their original capacity. On the inverter Sunynk is the only real choice at the moment I have been running completely off grid with 2 x Hubble 5.5 KW batteries and a 5 KW Sunsynk  I run a standard geyser and a few home appliances without any problems my Mono Solar array is oversized at 6KW but it still generates enough to keep me going on rainy and cloudy days I have not yet run out of battery power and generally only cycle my batteries down to 40% .

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