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First May with PV, but it's actually been a year since I installed the battery and what a difference it has made!
Two records fell this month:
- Daily generation max of 31.29kWh
- Peak PV power of 6.03kW

The 5 degree array is really coming alive with the higher sun angle, so generation has shot up.
I've accepted that I can't keep up with the daily generation anymore. Self consumption is down to 59% but PV contribution to house load is 98%.
Unfortunately, the slow response of the Solis at points means I'll never fully eradicate import.

Solaredge 539kWh
Victron 481kWh
Graig Fatha 402kWh

Solaredge & Graig Fatha are not PB's, yet with the rearranging of Victron system late last year it is a combined single month PB. Also my first 1MWh+ solar month.

Total 1,422kWh RE generated.

It brought a smile to my face when I checked my May generation and saw it was being reported in mW.

That was quite a month - after a slow start, finished off with an amazing 2nd half - to bring multiple all time record days (36kWh).
Final tally for the month is 730kWh, which is more than 100 above the PVGIS prediction

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marshman wrote: ↑Thu Jun 01, 2023 8:53 am

MrPablo wrote: ↑Thu Jun 01, 2023 7:42 am
Self consumption is down to 59% but PV contribution to house load is 98%.
Unfortunately, the slow response of the Solis at points means I'll never fully eradicate import.

I have a Solis inverter and a heatpump in an "all electric house". I keep seeing references to the "slow inverter response" causing import to be measured. Last month according to the "Acrel" meter attached to the Solis I imported 0.04kWh. The "proper" electric meter measured 1kWh of peak rate and zero off peak for the month, but then it only has a resolution of 1kWh so could have carried over 0.996kWh from April! So I don't believe so called slow response is an issue.

0.04kWh in a month is mind-bogglingly low, I dream of being able to reach that.

I have a IHD from Glow (https://shop.glowmarkt.com/products/dis ... -customers) which communicates directly with the smart meter (ie the only meter that actually matters, the one I get billed via), but it's a lot more useful than most IHD as it can be connected to WiFi and spits out lots of data every 10 seconds:
So this is directly from the electricity meters registers. Stuffing this into Grafana means I get extremely detailed import/export figures on a very granular basis.

I do concur with you on the huge kW power swings, I sometimes see many hundreds of watts or more in the "power" section, but they are very transient and the resulting "import/day" barely moves because of it.

That said, I do see persistent accumulating import/export - you can see above the week is 0.533kWh (the month is lower because its the 1st of June). I actually found it got worse after installing my Victron Multiplus. The Luxpower was actually better at keeping these closer to zero, which is a disappointment. I'm considering getting an ET112 or something which are supposed to be more accurate, but then the tradeoff is they're slower to react than a CT (which I'm currently using) so I'd likely be no better off.

All in all, it's only a few pence a day ultimately so I'm obsessing over tiny details. Just the OCD in me wishes my import/export could be maintained a lot closer to zero - not least because I'm not supposed to be exporting at all

I have both a Glow IHD and also an LED pulse sensor on the smart meter itself, both tally with the readings Octopus use.
The pulse sensor results in an energy granularity of 0.3125wH (3200 pulses per kWh), which is massive overkill but at least accuracy is never an issue....

For me, the inverter response is not quite fast enough for certain appliances, particularly the portable induction hobs and breadmaker.
Inverter capacity is no longer an issue now I have the 6Kw unit.

As for the meter that came with the inverter, my understanding is that the inverter queries it once per second (Acrel meter and S5-EH1P inverter), so it's quite possible to fill the meter energy accumulation bucket one or more times before the inverter acts to balance the load.
Also seen when you have a day with fast changing cloud cover.

All in all, it's a minimal problem. Just interesting to see that short of a very fast acting control system, it's unlikely that a grid parallel topology will see perfectly zero import (with 'spiky' appliances anyway).

My results for May were:

3.87 kWp, slope 50 degrees, due south, lat 57.15

Total generation: 419kWh

Daily average: 13.5kWh

Generation per kWp: 108.3kWh

Daily average per kWp: 3.5kWh

PVGIS: 401kWh

%PVGIS: 104%

Worst May since install, 60kWh below the average and 143kWh less than May 2018.

1121.9kWh

Low 13,6kWh
High 56.6kWh
Average 36.2kWh

Destinations:
35% to house
27% to battery
38% to grid

Say it every month, need more battery (or another EV that can stay at home during the day!)