My Photovoltaikanlage

[Alberto]

Installed late 2019, ca 9.5kWp 29modules 13keur, half module East- the other half West-, no shadow, near Hamburg
I am posting this for fun. Maybe someone is interested.

I had more recorded data but ouch a computer glitch and lost them, so starting again and I now have only a shorter recorded period. I will update the figures as I acquire more data.

I also simulated getting a domestic Akku (sorry, no data shown here), the only quotation I got was 10kWh 10keur (vendor said smaller Akku make no sense, and cost would have been almost identical). Over its 20yr lifetime this would have lowered my grid bill by 1keur (NOT per year, but in total over its 20yr!), so a net loss of 9keur. Still a good deal says the vendor Oh, and this assuming the 10keur Akku lasts 20yr as the vendor said, not 10yr as the manufacturer warranted.

Any question, just ask

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[Frantic]

10kWh 10keur is a rip off. Neither in Munich area they will dare to charge so much

I got my PV system commissioned a pair of days ago. After a lot of thoughts, calculation, simulation, my conclusion (at least in my usage case) is that a 5Kwh battery was ok to have. More would not have been worth.
Here https://www.bonotos.com/ you will find a useful excel file.
Also this is pretty interesting: https://pvtools.sektorsonne.de/

The "problem" in your case is that most probably you will need to change your inverter into an Hybrid one in order to support the Battery. So it is not just the cost of the battery. Maybe in those 10k was included also the new inverter ? Then is not a complete rip off.

[Alberto]

I won't get a battery. Bad for environment AND bad for my wallet. And extra hassle.

Ironically, my inverter is actually already compatible with a battery (I know most aren't), I wouldn't need to be changed.

Bear in mind the quotation was 2020, some time ago, perhaps less expensive now, can't be bothered to check again....

It was fantastic observing the vendor trying to convince me that despite the overall financial loss, 9k€ over the 10/20yr battery life, it was a great financial investment.

But @frantic, what battery quotation did you get?

[Frantic]

I chose a BYD HVS 5,12 Kwh. 3800euro included installation. Initially I was going for a Huawei one, same size, few hundred euro cheaper. The problem with the Huawei one, at least with the 5kwh size, is that the max throughput would have been 2.5 Kwh. You turn on two fireplace on the induction stove and you start to take part of the electricity from the grid.

Price/Kwh are definitively lower than 4 years ago but we are still at a point where you have to do your own homework to understand if it is worth or not. It is not yet a no brainer decision. You have to consider also that an Hybrid inverter (needed if you install a Battery) cost slighlty more of a normal inverter of the same size.
In our case, our electricity consumption profile justified the battery.
We both work, even when we work from home we hardly can cook dinner during working time.
Regarding dinner, we are not "brotzeit" people, we cook for real (italian and iranian, what can you expect ? ) . Culturally (but working time help on this ) we don't have early dinner time. Dinner time for us is between 20.00-21.00.
If we need to do a washmaschine washing we can do just after work. Lights in the garden at night, TV and computer, at evening and night.

In this first 2 days the battery is doing exactly what we need and we are discharging it each day. The more you "use" (charge/discharge) your battery the more is your return of investment.

All in all according to my calculation, the plus of the battery in our case will be:

1) One year less for return of the complete investment (PV System and Battery).
2) Much more flexibility in how to use electricity. Of course when we can we will try to switch to day time activities that requires electricity.

[Alberto]

@Frantic

very interesting, thanks a lot for sharing.
From whom did you buy it and get it installed? Small local company or big name?

In our case definitely Akku not worthed. I wrote it many times: nett loss of 9keur. And this assuming 20yr lifetime the vendor said, if instead the lifetime was 10yr as the manufacturer warrants then the loss would be more.

Sei Italiano anche tu? Oppure tua moglie? Ciao

[Frantic]

I got the battery together with the PV System.
I gathered several offers from local companies, I did not want to go with big companies that then hire sub or sub-subcontractor with the risky of no quality check and other crap.
I was asking to each company an offer with and one without battery in order to compare.

Yes I am italian.