Solar generation in the UK from November to February is generally very poor. You'll see a massive improvement from spring to late autumn. That'll be time to watch your generation.

I have an evenly split 4 kW nominal East-West array.  Your figures are much as expected, particularly with E-W orientation. For example, my generation 08/11/2021-13/02/2022 was 180 kWh - so low that it doesn't even cover consumption without an ASHP.  Total annual generation is ~4000 kWh.  Winter generation is worse than the S-facing configuration but it's higher in early morning/late evening in summer.  Here's a >>link<< to some modelling I did on this.

Your contractor will have misled you if he suggested that an E-W orientation could deliver surpluses in winter.

Ours is E/W and generating similar in mid winter. Currently we are getting 5Kwh on a sunny day.

Posted by: @katcesca

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Ours is E/W and generating similar in mid winter. Currently we are getting 5Kwh on a sunny day.

What size is your solar PV system?

@katcesca wow I wish I was getting 5kwh per day 😊

Posted by: @lfranklin

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@katcesca wow I wish I was getting 5kwh per day 😊

We have had output from our solar PV system every day since it was installed over 10 years ago. I think that the lowest daily production was 30Wh and the highest over 25kWh.

The main determining factors are the cloud cover, any form of shading, and the orientation and angle of the panels. Battery storage can of course help smooth out the peaks and troughs when those 'pesky' clouds come along, and also allow excess daytime generation to be stored for later use.

If you suspect that you are not obtaining the expected output from your panels, then I would suggest monitoring the output on a sunny day, whilst checking for any form of shading that may be occurring.

Posted by: @lfranklin

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We had growatt solar system installed at beginning of Jan (16 x 405w panels as a split 10 on East 6 on West and a 6.5kwh battery) and I'm not convinced working right as only generating within a range of 0.8-2kwh per day generation at the moment which seems extremely poor for this size of system that works on PV and min 7 hours daylight at the moment.

As I am very unfamiliar with PV I was hoping someone may be able to advise if this generation sounds correct or not? We were sold the battery in that we could store excess electric on shorter winter days to use on an evening but at the moment we aren't producing a drop in the ocean of the electric the ASHP is costing lol.

Have you got a variable rate tariff and have scheduled the Growatt battery to charge during cheap rates to supply during standard and peak rates? It's a good way to use the battery to your advantage in winter when there's little solar PV generation. The charge and discharge combined efficiency is around 90% by my estimate, with about 85-90% of the 6.5kWh battery capacity useable.

I have moved onto Cosy Octopus to do that, I'm saving around 20% off my bill each day in doing so, with the ASHP on 15hrs a day or so and generating hot water each day in the low rate early afternoon period. I've probably offset the further increase in tariffs in April, but by then, my 3.6kW 9 panel solar PV will be contributing more.

I'm quite impressed with my south facing install, even with low solar inclination as per now it provided 11kWh yesterday. E-W is not optimal, but can work. Whatever you micro-generate is free energy. Unlikely you'll ever make much of a dent in the ASHP energy requirement in the winter months, but over a year....

@allyfish  at the moment no as not got a smart meter but I keep checking if available yet. Moved to Octopus recently with that exact intention when I am able. Can I ask what scheme you are on for selling excess back to them in summer?

I agree producing electric off grid is great but looking forward to recouping some of the large amount of money laid out for the system in first place.lol.

@lfranklin ah, yes, you'll need a smart meter for Cosy. My PV export tariff is 'Outgoing Octopus 12M fixed' their standard 15p/kWh fixed arrangement. OVO were offering 4p/kWh!!

That said, I have an i-Boost diverter, which kicks in when the Growatt battery is fully charged and 200W surplus generation, so don't plan on exporting much. I want to use all I generate at home.

Octopus set up everything super quick, both my switch to them, initially onto a standard variable price cap tariff, the application for Cosy, and the Export tariff. All done within 2 weeks. Ovo sat on my export generation application for 8 weeks and I heard absolutely nothing back before giving up on them and looking elsewhere.

@allyfish can you tell me a little more about the diverter and now much it costs/how it works?

@lfranklin used to divert excess solar PV generation into a system hot water tank via the 3kW immersion. About £350-400. Friends with them have said they provide practically all their daily hot water requirements all through the late spring, summer & early autumn. I've yet to see mine through the summer.

I have an i-Boost

https://www.marlec.co.uk/product/solar-iboost/

but Eddi is a similar unit 

https://www.myenergi.com/eddi-power-diverter/?gclid=EAIaIQobChMI2tDp8oTy_AIVxNLtCh07eQypEAAYASAAEgLxmfD_BwE

They measure your outgoing energy via a current transformer on your supply at the meter box, any surplus PV it will divert into your hot water until the cylinder demand is fulfilled. Can divert from 100W upwards.

There's no intelligence between the Growatt battery discharging and the iBoost. There's a potential that the battery discharge may feed the solar diverter. I've found this doesn't happen with the Growatt SPH5000 hybrid inverter and i-Boost combo, but that's probably just luck. The Growatt inverter is quite sensitive on the control, balancing battery discharge power closely to load, whereas the iBoost is a little slower to respond.