On-grid domestic battery storage

QrizB

QrizB said:

My cells arrived safely from China but unfortunately my BMS is duff so my battery isn't connected yet.

A quick update for anyone interested.

My replacement BMS (a Daly Smart BMS, 16S 60A) arrived from China in the week. This afternoon I've hooked up the cells, plugged in the BMS and attached it all to the Sofar ME300SP that's been waiting for it. I had a bit of trouble with current transformers (getting them the right way around and replacing the crimped extensions with soldered ones) but it all seems to be hanging together.

All I need now is for these rain showers to blow over and give me some decent sunshine!

Edit to add: the sun came out!

Martyn1981

Thought this news might be of interest. It caught my eye because it mentions subsidies for batteries. Way, way back, I suggested that subsidies should be provided since batteries help so many vested interests - they can aid the rollout of RE, which benefits Gov targets - they can aid leccy suppliers, since they reduce the amount of peak price leccy they need to buy to meet demands of customers on a fixed price tariff - and they benefit the local distribution network by helping to reduce peak loads.

In fact, 'subsidies' is probably the wrong word, and it's more about partners sharing some of the costs and benefits.

Anyway, enough waffle and dreams, here's what's happening in the Australia State of Victoria:

To speed up the process, Victoria is offering subsidies for household battery purchases, with the provision that energy companies are allowed access to stored power during peak energy events. This would seriously reduce demand on the system at peak hours and reduce costs for all concerned. Much cheaper than putting in a big battery or another gas-fired power plant.

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Solarchaser

QrizB said:

QrizB said:

My cells arrived safely from China but unfortunately my BMS is duff so my battery isn't connected yet.

A quick update for anyone interested.

My replacement BMS (a Daly Smart BMS, 16S 60A) arrived from China in the week. This afternoon I've hooked up the cells, plugged in the BMS and attached it all to the Sofar ME300SP that's been waiting for it. I had a bit of trouble with current transformers (getting them the right way around and replacing the crimped extensions with soldered ones) but it all seems to be hanging together.

All I need now is for these rain showers to blow over and give me some decent sunshine!

Edit to add: the sun came out!

Great news that you are starting to make headway with it.
Unfortunately August tends to be fairly dull, but it will give you some time to play before the brightness of September comes around.

QrizB

Three weeks in and everything is mostly working.

I've tidied up my batttery enough that I'm comfortable posting a photo. Not a very good photo, sadly, but it shows the basics.

Sixteen 25Ah cells, most negative in the bottom-left and most positive in the top-left. The thick blue cable and all the skinny ones connect to the BMS (red and black, bottom-left) while the two thick black cables go out via an XT60 connector to my Sofar ME3000SP. The twin black cable in the centre is the BMS temperature sensor while the bottom black cable is for the BMS Bluetooth dongle which is just about visible in the bottom-right.

I've set the Sofar to charge at 10A max and discharge at 25A max, which is about 500W and 1250W respectively. I don't want to drive the cells any harder than that and it's enough to meet most loads while the sun shines (including kettle or washing machine) and to comfortably cover our base load from dusk to dawn.

Ther total capacity of 1.25kWh isn't enough to last through the night, even at this time of year. I've got a set of 60Ah cells on order which will boost capacity to 4.25kWh and hopefully cover that.

We're not big users (and we've been away from home for roughly half the time since I commissioned it) but our consumption seems to have fallen by between one and two kilowatt-hours per day.

QrizB

@Martyn1981 wrote:

Martyn1981 said:

Ever bigger batteries being deployed. Now an order for 2GW / 6GWh, though the timescale is not given.

I can't compete with that but my 60Ah cells did arrive from China today, along with my invitation to join Octopus Go! I now know what I'm doing this weekend

newbuilder

I have added another 2400 uhome battery and had faults. After placing it as the master and re dipping the others it has worked but the balancing seems off. It has the new battery a good 8-10percent lower than the three established batteries. I have tried the unhook all data and start the batteries up and let them settle but nothing happens. Any ideas how to balance these. All Volta are the same across the batteries and the use of batteries stops when one reaches the 12%!threshold. 

EVandPV

newbuilder said:

I have added another 2400 uhome battery and had faults. After placing it as the master and re dipping the others it has worked but the balancing seems off. It has the new battery a good 8-10percent lower than the three established batteries. I have tried the unhook all data and start the batteries up and let them settle but nothing happens. Any ideas how to balance these. All Volta are the same across the batteries and the use of batteries stops when one reaches the 12%!threshold. 

I had the same issue when I added a 3rd Pylontech.
I messed about with them for a while but couldn't get them to balance so just left them to it and after about a week, they balanced by themselves.
The 3rd battery, which is slightly older and has an older firmware, sometimes drifts slightly out of sync with the other 2 but it always balances after a full charge and falls back in sync.

newbuilder

Oh me and patience!!! Need to keep the hammer, screwdrivers and manuals in a locked cupboard then. 

lisyloo

Hi, new to this thread.
whats the rough up front outlay for sonnen for 3.9?
and is it worth 

EDIT: this looks like thousands. How does this stack up?

Solarchaser

Do you have a quote you can share?

I mean I'd literally just be googling the cost of the battery, which you can obviously do yourself.

You haven't mentioned which inverter?