Solar panel production figures

14.8kWh here today @ 5.05 efficiency. Battery lasted all night and through the day so only imported 900watts, but exported 5.3kWh for next to nothing.
 
Sorry if this isn't the right Forum for this question, but I thought people who are interested in all the figures would be able to help.

I have a growatt inverter and battery system that I charge at night for the cheaper rate on octopus flux. I have a spreadsheet that I want to track savings on but I'm having trying to work out how much money I am saving charging the battery at night.

Does anyone know what figures I would have use to work this out? I really only want to look at numbers at the end of the month and not have to note things down daily. The shinephone app only seems to give total charge daily and doesn't differenciate between ac charge and solar charge.
 
HungryHippos said:
Looking at your pvout you've had a pretty awesome April for generation, even ignoring the larger panels and such!
Click to expand...

I've just looked at the full information on the SOlarEdge web dashboard for April.

2016 513 kWh
2017 562 kWh
2018 423 kWh
2019 492 kWh
2020 570 kWh
2021 550 kWh
2022 553 kWh
2023 481 kWh (Projected currently at 418)

So 2018 was the worst at 423, this year looks to be the second worst.

The Average is 518, so we are below average.
 
Can anyone help me to work out what a solar installation is likely to save me per year ?
I tried to use a couple of calculators online last night but the result of one of them suggested that I would only put about 600KWH per year into a 9.5KWH battery with a 6kw solar panel install, and in total would only be using around 27% of produced energy, this seemed very low to me and makes the battery almost pointless. Real world though I would expect to full charge it most days from April to September and use it all up overnight which would be about 1500 - 1700kwh
currently use around 600 - 700 kwh per month
South west facing "normal" pitched roof.

not sure on exact system yet as am trying to weigh up install cost vs payback time etc.
I imagine I would need a 6kw system with a 9.5kwh battery ?

I'm asking in here as you guys obviously have a firm grasp on real world figures/savings
 
MassiveJim said:
Can anyone help me to work out what a solar installation is likely to save me per year ?
I tried to use a couple of calculators online last night but the result of one of them suggested that I would only put about 600KWH per year into a 9.5KWH battery with a 6kw solar panel install, and in total would only be using around 27% of produced energy, this seemed very low to me and makes the battery almost pointless. Real world though I would expect to full charge it most days from April to September and use it all up overnight which would be about 1500 - 1700kwh
currently use around 600 - 700 kwh per month
South west facing "normal" pitched roof.

not sure on exact system yet as am trying to weigh up install cost vs payback time etc.
I imagine I would need a 6kw system with a 9.5kwh battery ?

I'm asking in here as you guys obviously have a firm grasp on real world figures/savings
Click to expand...

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%).

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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).

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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).

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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
 
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Armageus said:
The system is rated at 298Kw, consisting of 1104x 270W JA Solar modules, south facing - 10 degree tilt, and 9x Solaredge inverters.
The system was installed in 2018, and generally supplies between 18 and 24% of our site's energy demand.

We are currently having a 2nd bank of panels installed (~550, with 3 further inverters), which should be online in the next couple of weeks

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Click to expand...

#Commercial

Just checking in, but upgrades have happened


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rubbish day so far, ticking over at 1kW but so grey dont think this will change much, might have to cancel my evening dump unless I get a chunk of battery charged sharpish!
 
@MassiveJim Put as many panels on as you can, and perhaps double up on the batteries. Just make sure you get an MCS certificate, you can then get good export payments on Octopus Flux. I aim to fully charge my battery as much as possible off peak at 20p a kWh, then excess is exported at 23p, in the winter you need the battery to last through to the next cheap rate period to charge again. I've even export some from the batteries in the peak period at 36p kWh.

As for costs, and ROI I've no idea, but my electric bill is -£18 most weeks although only been on the new tariff since 11 April, and that's only going to improve as we go into summer.
 
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