Need some help with a Huawei three phase solar inverter and battery

Forums › Home Workshop DIY › Need some help with a Huawei three phase solar inverter and battery - reporting all up the wazzoo

1 | 2 | 3 | 4

naturalhighNZ

32 posts

Geek

#3198571 21-Feb-2024 21:59

SomeoneSomewhere:

Transpower runs electricityinfo.co.nz.

You're most interested in Bream Bay BRB0331, but the prices at Otahuhu (OTA2201) are almost identical.

But the only way to benefit from this is to go to a spot price power supplier, yea? Like Flick? Are there others that might be available where I am?

Samsung

Shop now on Samsung (affiliate link).

eonsim

384 posts

Ultimate Geek

Trusted

#3198579 21-Feb-2024 23:29

naturalhighNZ:

SomeoneSomewhere:

Transpower runs electricityinfo.co.nz.

You're most interested in Bream Bay BRB0331, but the prices at Otahuhu (OTA2201) are almost identical.

But the only way to benefit from this is to go to a spot price power supplier, yea? Like Flick? Are there others that might be available where I am?

Ecotricity offers a spot price plan. Note such plans are relatively high risk unless you have enough battery to simply drop your usage to zero when spot prices go crazy, or you have enough battery to supply the house and sell back to the market during crazy periods.

Pretty sure there have been instances of spot prices reaching over $3-4 per kWh in the last 12 months.

https://www.emi.ea.govt.nz/Wholesale/Reports/G42MES?_rsdr=L364D&DateFrom=20230222&DateTo=20240221&_si=v|3

If you can sell during that period it's great, but if you have to purchase at spot prices you get burnt badly.

CrazyM

110 posts

Master Geek
Inactive user

#3198589 22-Feb-2024 06:13

naturalhighNZ:

CrazyM: You are close now, change the signal point to show Pa Pb and Pc and that will show the loads on all 3 of your phases. The graph just currently shows phases b,c and then the total of all 3 phases

Okay I think I got it - love to know if any insights or anything I can take from this. What I note, and probably my issue with the installer, is that I very clearly am importing at times when I'd rather not be related to the phasing.

This plot basically represents exactly what your power company is seeing and charging you for. Consider each phase as a separate electrical connection that you get charged for when it is negative (i.e. below the centre line), and you get paid when it is positive)

It looks pretty good to me. I dont think there is anything you need to do as far as balancing phases around your house. Looking at the plots I would surmise...

The inverter looks well sized to your panels (at least on this day) as it doesnt spend much time clipping (flat spots at +2200W)
Your hot water cylinder is on phase A and uses a lot of grid power from 10pm-2pm (yellow)
You have ~300W of fluctuating loads on phase A 24 hours per day, probably chest freezers or an HRV etc...
Your battery seems to have charged from the grid between 4am-6am shown by all 3 phases having a constant draw of ~800W (pink)
I expect your kitchen in on phase B with its occasional large loads at 10am, 2pm (probably boiling the jug) and 5-7pm (cooking dinner) (orange). I expect your battery also discharged during 5-7pm as you can see phase A go more positive than expected and the phase B loads gets truncated slightly.

It is slightly hard to see what you battery is actually doing with its charge/discharge cycle, perhap it can also be overlayed on this graph but it looks like it was never charged with solar. Its just taking your power charged from your night-rate and using it at your time of peak-rate, which is the right time to use it.

naturalhighNZ

32 posts

Geek

#3198835 22-Feb-2024 18:31

Nice man, that is amazingly accurate - though I think the "hot water" is the EV; might be on the same phase as the hot water though (which is heat pump cylinder on a timer to exclude peak periods only). This was a weekend so I guess not the norm but good to know that things are looking good actually.

Unfortunately with the way the Huawei app is designed I don't think there is a battery overlay to this screen that I could see. Not definitive, but I don't think I can overlay it sadly which is a bit of a shame but the battery, whilst not eliminating peaks, is no doubt helping to reduce the cost. The shame is that if I wasn't on a three phase system I actually doubt I'd be paying much if anything during peak periods - but the problem of course being that my loads will exceed the maximum phase for the inverter. That's the sticking point still for me with the provider - like seriously, why was this not explained face palm.

1 | 2 | 3 | 4