Home Assistant and solar on balcony

Hi everybody,

my landlord has finally given clearance for solar on my balcony, so I’m starting to think about it. I’m living in Germany, so according to the German regulations, I’m thinking about 800W (I guess that’s two panels each 400W each). Additionally, I’m considering getting a little battery. Here’s the rational: I have a minimum energy usage of around 70W. If I want to have that energy for the night (say, 14 hours), that adds up to around 1kW, for which batteries are pretty affordable by now. However, if I spend all the money, I want to have all the fun. So here’s what I would like to do:

  1. Get solar panel, battery etc.
  2. Get something like this meter to measure my apartment’s energy consumption.
  3. Use Home Assistant for control to minimize energy consumption through my energy provider:
    • If apartment consumes X W, make sure that panels deliver X W to the apartment, and the rest to the battery
    • If panels can not provide enough energy, make sure that battery helps

So here’s my question: Does that make sense, and is it possible? And if both answers are yes: Has anybody built something like this? Care to share your (exact) hardware configuration, and maybe your approach or even some code?

Thanks
Christian

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I have similar plans but I plan to do it with an Easymeter Q3. That meter is supporting the EDL21 integration. Even though I could do this myself I will contract an electrician since I am renting the apartment and they probably want it done properly.

I have read in the docs the page “Integrating your solar panels” and after a bit of googling I found the following forum thread: Monitor your solar PV system in Home Assistant

My priority will be in the end that nothing of the software depends on any cloud integration.

Edit: Sadly my landlord didn’t allow me to mount the panels as such I won’t be able to execute the project.

You can find a pretty good article (in my opinion) about “Nulleinspeisung” with balcony power plants and Home Assistant here: https://martinteske-blog.de/home-assistant-nulleinspeisung-balkonkraftwerk/

Unfortunately, I can’t give you any empirical values by myself. I find the concept of zero feed-in very interesting.
But in our 2-family house we have a average base load of 200 watts. The utilisation rate of the energy produced by our 800W balcony power plant is 92-95% on average. Unfortunately, this still makes a storage system economically unattractive in our case. :-/