I am starting to use home assistant to better control my inverter. Home assistant reads the inverter settings - see screenshot.
My inverter is 5.0kW, but it says the maximum export is 6kw?
What does the 5kw refer to? I assumed it was 5kw dc to ac (whether from the solar or battery).
I know the export can be limited in line with DNO limit, but why would the inverter have a limit set greater than its capacity. A 5kw export limit from a 5kw inverter makes sense, 6kw doesn’t, unless I have misunderstood something.
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Did you installer apply for the export limit with your dno? Export limit 6kw i think is the export to grid limit. Solar + battery export total.
Welcome to the rabbit hole of Home Assistant !
You don’t mention it, but I assume you are using GivLocal or GivTCP to talk to your inverter. Judging from the names of the entities I’m guessing you have installed GivLocal; I’ve only ever used GivTCP but I know there are happy users of GivLocal and some of the controls are a bit easier than GivTCP.
To answer your question, the 5Kw on your inverter refers as you say to the max DC to AC your inverter can convert. The 3600 is the figure in watts that your inverter can charge or discharge in/out of the battery, i.e. 3.6kW (its not quite this due to losses and how its measured, you’ll probably find you get a bit more than 3.6 on discharging and a bit less on charging), so of the 5kW max DC inverter throughput, 3.6kW can go in to the battery and the rest into the home or exported.
The 6000 is your DNO imposed export limit based on how much the DNO believes your grid can handle. You are correct, you can’t achieve this with a 5kW inverter, but if in the future you had a second inverter it would still be respected by this inverter so it has to be set by your installer.
Thank you for clearing that up.
I am using givTCP.
I do code, but have not used YAML before so it is a bit of a learning curve.
Currently looking at a calculation so that remaining battery capacity (which varies a lot day by day especially in the winter) is exported just before it begins charging on cheap rate overnight.
Most of my solar (except for the base load) is exported as my export rate is 2.5x my overnight import rate.
This potentially saves me another £400/year.
no problem!
Having said that the 6000 is the DNO imposed limit, I went and looked for that entity in Home Assistant myself as I wasn’t familiar with it, didn’t think it existed in GivTCP, but it does (just hadn’t seen it!), and mine too is set to 6000W.
I have no DNO imposed export limit and I am pretty confident that GivEnergy set mine to 10,000 as a result, so this value confuses me.
Looking at my HA long term history I achieved peak export power approaching 10kW a couple of times in June 2024, but as this is aggregate into hour summaries I probably did actually exceed it. Will have to look again this summer and see what happens
However yesterday I hit 8kW export power yesterday:
and the inverter didn’t clip out at 6kW, so my conclusion is that this is probably a wrongly mapped register on the inverter and can thus be ignored!
I started off with Home Assistant to get a handle on what my inverters were actually doing (I have two 5kW hybrid inverters and the GivEnergy app and portal struggle to display them correctly together). I then wrote my own automations and then scripts to control charging and discharging around best times to use Flux, and then after a while I moved to Predbat: Predbat Documentation
Predbat is very configurable battery management software that predicts your solar generation and home consumption and generates an optimal plan for your battery to minimise your expenditure/maximise income
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No dno limit? That’s unusual. It is usually in the DNO acceptance letter. Usually matches inverter size.
I just double-checked the letter, it is actually 10kW, matches my inverters
