Solar PV battery options

Thanks!

You’re in the same situation as me in this regard. I already have 10kWh of battery; which I charge every night between 2-4 am on the EI night boost. This is working well in summer when the battery only drops to about 60-70 % by 2am due to the longer days.

but in winter; I’ll be hitting 0% before 2am And My battery can only charge at 3KW from the grid; so to get it from 0-100% would take between 3-4 hours. Which would mean that I would not be charging it exclusively from the boost rate.

So what I’m going to do is charge the battery between 2am - 8am majority of the power will come between 2-4 am and then some on the off peak between 4-8 am. But importantly I won’t start discharging the battery until 8am as it will be set to charge during this time.

The main thing for me is to avoid any grid usage between 8am - 11pm when it’s the highest price. I believe I should be able to make the 8am - 11pm (15 hours) on 10kWh battery plus whatever bonus kwhs the panels generate. Some days it might be feck all; other days might be 6-10kWh.

this is also shifting behaviours like washing machine during the day in summer to scheduling it to come on between 2-4 am in winter.

With a bigger battery and more powerful inverter, you could actively trade electricity. Buy in your supercheap slot between 2-4AM and then sell back to the grid when you least need it. And of course if / when we get super variable rates, soak up all that electricity from the grid when the price is negative, like in the UK and the Netherlands last week. In a typical Irish house you got a 12kva connection, which means you can draw up to about 15kW from the grid. At €0.25 / kWh negative, this makes you nearly €4 per hour, fully automated. Well that's the plan 😁

But seriously, this is more important in the move to renewable energy than renewable energy generation itself...

this is a really good strategy. the new flogas community tariff is hopefully indicative the way the market is heading (especially for those relying on night rates to charge their battery ahead of the day rate period).

Any recommendations for the “fastest battery charge” for an inverter?

@graememk - "8.8kw sunsynk!"

FYP 😁

190A charge / discharge. About 3 times what a Solis 6kW hybrid can do...

Where’s the best place to pick these up?

I purchased a 5.5kW version directly from China. Took a very long time but I think at that time they were quoting 1.7k for the 8.8kW version DDP.

I'm on a NC6 from the original solar install so didn't apply for this unit. The Deye/Sunsynk is for replacing a Sofar ME3000SP in my case.

The setting wouldn't be an issue for our grid.

ITS wouldn't ship to the north when I enquired last year. They said their couriers had been refusing requests to ship stuff across the sea.

Perhaps things have changed since, you'd have to enquire.

There's something to be said for plug and play especially for those of us who wouldn't have a notion when it comes to setting up a CALB battery.

Fair enough, forgot that the Dyness were 15S too. You're still a maniac 😂

I wouldn't use lead acids in a room you spend a lot of time in like an office, unless it is very well ventilated. Like a barn or an uninsulated shed would be more appropriate.

Still not sure why you didn't just buy a few more Dyness? Pylontech tiny pouch cells are seriously poor. I've opened several of them (2.4kWh), and there was plenty of bloating. And I had an interesting experiment hard discharging a bloating pack - no fire but let's just say we got a massive vent and the stink of electrolyte took ages to disappear from my shed 😁

I sure hope the 4.8kWh do not use same tiny 25Ah pouch cells. That said I don't really know what's in the Dyness either. If it were up to me and I was forced to buy ready made batteries (and pay for 8 * expensive BMS while you'd only need 1 😀), I think I'd go for generic no name packs from AliExpress with decent EVE cells. Was doing Seplos / Mason DIY kits not an option?

If you don't change your mind and the packs come, try and not connect them as Pylontech says you should, as that is wrong. They need to be paralleled via shared central busbars, not via those connecting cables they supply.

Any links to these busbars you suggested? Sounds like a good idea for balancing.

With 8 packs and 4 dyness packs I think nothing will be hard discharged as even putting in or out 100A (the solis limit - notionally anyway) is not even 0.1C of my 1200AH pack combined.