Solar PV battery options

For the uninitiated; what is 5C? It’s clearly something to do with charge rate??

Ha. I remember something when I had my lipo battery for my diy drone I made years ago and something to do with how fast you could charge it was measured in C or S. that’s why I was making the jump here. But yeah it’s temp in this cast. Silly me :)

Yeah another story we keep hearing. I will be very surprised if we can buy sodium ion batteries for home use delivered here for less money than lithium iron phosphate before 2024 and I am usually more optimistic than average on these things...

How much is it likely to cost to make up a 20-30kwh calb battery system. Cells, bus bars cables etc?

while not directly related is it possible to have a second inverter feed into and from a second consumer unit? I take it if you were charging batteries here you’d be buying from the grid even if your other inverter was feeding to the grid at the time.

I ask because I don’t have room for a diy battery next to my inverter in my house the second one would be in the garage and there’s no easy way to run cables between them.

Thanks for that. I’m probably going to add additional panels on the garage down the road so would need a hybrid inverter in the garage too?

You could have a second hybrid inverter or storage inverter no problem if your first inverter is a non hybrid. The new hybrid inverter would pick any excess power generated from the other inverters arrays also and send that power to charging it's own batteries. The CT clamp on the hybrid will detect if any power is going to/from grid and act accordingly.

I’ve just had the system installed in the house.

I don’t have space though for a diy battery close by so the detached garage is the next best option. It has a consumer unit for the garage and the heatpump is located here too.

Long term i’d like to put 4kwp on the garage and small shed roof here at it is all south facing and will supplement my winter units based on some of the figures in the threads and the solar calculator. There isn’t a neat way to get cables between the two locations (asphalt concrete etc and I don’t want to run cables above ground, I don’t like the look ocd I suppose). Having watched the videos and following the threads here I think I could probably make up a decent calb battery say 20kwh in the garage.

Really what I’m asking is what is the best set up to have the two arrays work together, so best inverter etc and how they actually work together as I don’t understand.

House set up 8.4kwp, 6kw sofar hybrid inverter with 9.6kw dyness currently (possibly add another 3.6kwh unit here if I get one at the right price)

Garage set up could be 4kwp more or less depending on what I can fit, inverter as recommended with a 20-30kwh diy battery.

In my head I’m trying to set up to be totally off day time units in winter with weather like this and off grid units almost completely during the better solar periods. Now we’re using 50-80kwh but usually usage would be between 10-20kwh from end of April through to mid October depending when space heating kicks in. An Ev will be a consideration in the future once the wife’s car dies.

When energia worked out by bill on the phone yesterday they used their new rate forgetting I was on the ev rate in September and the difference was €200 I wouldn’t be long recouping my current investment once the better rates go and even quicker when they take our day night rates.

I will run what we have for at least 9 months and work out my actual payback and educate myself as much as possible to build the battery and on home automation which is where I probably need to go next. Tapos are on the way but a short term fix.

Ive no idea if my thinking is flawed so please destroy what’s above if there are better, more cost effective ways of doing things. I know the off the shelf battery in the house will attract disdain 😂 but I’m married and I’d prefer to keep it like that for now so couldn’t really go any other way.

Thanks

So for now it isn’t possible?

most likely I buy a regular grid tied inverter and put my hybrid in The garage. Sell off the dyness batteries and set up the diy battery in the garage.

or

Set up the garage system with a regular inverter and have that feed to the grid and set up the diy battery outside with the dyness inside or are both batteries still in conflict or is that ok if they’re on the same inverter ?

Some inverters (the sunsynk) allow you to set them in parallel and each can have their own batteries and work just fine.

As far as I know (could be wrong) the Solis do not allow you to that with their hybrids but you can parallel the non-hybrids just fine.

so from what I read the “sofar2mqtt” links to home assistant and allows you to control the inverter remotely. As your suggesting it I’m guessing it can charge both the dyness and a diy battery. I set up the standard Pv inverter in the house and move both the hybrid inverter and dyness to the garage then link in the diy battery there.

now I need wireless in the garage but that’s something I had intended on doing any way.

looks like I need to buy the home assistant for dummies starter book for Christmas.

thanks @championc @SD_DRACULA @irishchris for all the input

Yes sub €1400 is the target for the 200Ah CALB cells. Ordered 11/11 and getting 30/12, that's 49 days so pretty good going although I would normally expect more in the range of 60-70 days. Ordered a bunch more last week (23/12) and paid €1364. You need some sort of sale for these prices, the regular price is higher. Keep an eye out on PWOD official store.

Is it typically better to set your currency to dollars and pay via Revolut?

You're not missing anything, except that that price is gone back up to the normal level and that the VAT comes off when you buy. So €1827 in your case ex VAT. Keep a look out every day or two and buy when they are on sale. A few coupons take a bit of money off as well.