Solar panel production figures

One of the hidden benefits of batteries is also that when generation is spiky, such as a sun/cloud day you grab all the peaks and store them
A solar only array doesnt do that so you can potentially be exporting a load and importing a load which the battery just smoothes out
So even a smallish battery makes sense. Its just that bigger is better ;)

I agree with previous posts, within reason as many panels as possible as long as you stay below needing anything more specialist, but whatever you can run on a 6kwh inverter (can be up to around 9kw of panels depending on manufacturer from what i have seen) seems sensible

The battery, views vary, but I found the sweet spot on a few calcs to be 50-70% roughly of your daily usage. Going after higher means your periods when your actually gaining from the extra are pretty minimal since even 60% on most late spring to early summer days should be enough to bridge the gap from generation one day to the next
Below your likely not getting as much benefit as you could from cheap(er) overnight units being bought and used in the winter primarily.
 
HungryHippos said:
Big systems are good, you get more in the winter when you need it the most, and you can export excess in the summer which helps pay you back some.

A lot of the install costs are just them "showing up" to do the job, so whilst there, adding more panels, or a slightly bigger inverter is worth it.

Your usage at 600-700kWh per month is higher than mine, so I think that would make you a good candidate for a solar install. My average is around 17 kWh per day, or 510 per month.

I have a GE system, which from what I can tell is one of the better consumer systems for features. Includes some good stats as well.

I'll let my data do some of the talking, this is from 01/09/2022 until today.

Home Chart (this is monthly home usage, and how much of the consumption came from Solar vs Grid vs Battery. You can see Battery was about 50%).



Generation Chart (this is how much Solar came in, and where it went. So 58% of my inbound solar immediately fed the home demand, with 31% being re-directed to battery, and 10% going to export to grid).



Grid In Chart (this is how much Grid was used. A lot of this was charging the battery off-peak for cheap rates, which were then fed to home in the first Home chart).



Conclusions? saving a bunch of cash, not using Grid as much (not free from using it though), and the best months for generation are yet to come.

Not much of my grid usage was at peak rates, a lot of that was at cheaper rates on Octopus Go, and more recently Octopus Flux.

I've already put 600 kWh into the battery from solar, but I would argue that I am getting a lot more utility from battery not just from solar feed in, but cheap off-peak charging as well.

Additionally I posted about my overall bills for 7 or so months, and even including gas and standing charges, it made for a good total compared to what I'd usually pay - posted it here: https://forums.overclockers.co.uk/t...no-referrals.18948056/page-1125#post-36299181
Click to expand...

Wow that is really useful, thanks. :)

What is the reason for exporting solar to grid, then charging the battery from the grid, rather than just using all the solar to charge the battery ?
 
MassiveJim said:
Wow that is really useful, thanks. :)

What is the reason for exporting solar to grid, then charging the battery from the grid, rather than just using all the solar to charge the battery ?
Click to expand...
time of use....... with the right tariff off peak energy costs a fraction of the cost of it at peak time so you can essentially day trade electricity if you want...
 
MassiveJim said:
Wow that is really useful, thanks. :)

What is the reason for exporting solar to grid, then charging the battery from the grid, rather than just using all the solar to charge the battery ?
Click to expand...

In Eco mode the priority for Solar is: House load => Battery Charge => Grid Export.

Once the battery is full, we're exporting, which on a nice sunny day you'd struggle to find enough things to power on to beat the generation.

With Flux tariff I also don't mind exporting a bit, I get paid £0.24 per kWh in the day, and from 16:00 - 19:00 it's £0.36, so export is good.

See my post here, I earnt almost £4 that day! Ron-ski will be pulling even crazier numbers.

Solar panel production figures

I would love a bigger system, but the roof doesnt allow it.... i am still looking at the rear of the property, but that will a future project if it goes ahead. i only paid a little over 5k for my system of 8 x 410watt panels and a growatt string inverter, no battery system. I put it in place, so...
forums.overclockers.co.uk forums.overclockers.co.uk
 
Today's figures are 33.61 kWh generated and circa 28 to the grid, some Welsh clouds came along so the afternoon wasn't as good.


HungryHippos said:
Ron-ski will be pulling even crazier numbers.
Click to expand...

@MassiveJim My electricity costs for yesterday were minus £7.03, that means Octopus credit my account £7.03 for just yesterday.

Yesterday I imported just over 14 kWh, this was between 2am and 5am when I pay 20.51p per kWh, then I run off the battery until the sun comes up, charges the battery until full then export the excess over and above what we are using for 23.18p per kWh. I exported just under 40 kWh, and roughly 10 kWh of that was during the peak rate 16:00 to 19:00 slot, earning 36.85p per kWh, some will be from solar, and some force discharged from the battery.

On Flux, due to the good export rates it makes sense in most cases to charge the battery as much as possible in the cheap rate period, that way if the day is bad you have plenty in the battery, if the day is good then you export for more than you imported although there will be some efficiency losses, this also makes managing it all very straight forward.
 
18.1kWh generated and 9.2kWh exported.

Better than expected as it was pretty cloudy all day, but it would be nice to have a proper sunny day from start to finish.
 
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