Solaredge and Batteries

[openspaceman]

That's why I'm going down Joeboy's route of adding panels just to charge a battery. I am hoping the 1.5kW will mean I can stay off grid most of October and March but also get in an extra 10kWh during the months of November, December, January and February, cutting my grid usage to around 400kWh.

[Joeboy]

That's why I'm going down Joeboy's route of adding panels just to charge a battery. I am hoping the 1.5kW will mean I can stay off grid most of October and March but also get in an extra 10kWh during the months of November, December, January and February, cutting my grid usage to around 400kWh.

One aspect that I have not spoken of is that by finally maxing out the available roofspace I now have a tremendous relaxed feeling. All the 'what if' is now gone. We had a very rainy day yesterday. At one point I was walking past under grey skies, checked and we had 1.1kW coming in which was more than i expected (really dreich). Later in the day it was 7.1kW for a few minutes as the clouds broke and the sun blazed onto cold wet panels. Both those values are excellent for the environment at the time as its all being caught and sent to the battery stack if not instantly used. For me it's definitely 'more panels, bigger net, larger catch' as the winner over gadgetry. All location specific of course.
There is also a real joy in doing for yourself and keeping the price low. After Nowtys original suggestion I am now in the enviable position of having two full on PV arrays grabbing what they can Far North and learned plenty on the way
Nowty!

[Oldgreybeard]

The PVGIS plot looks about right. 402kWh for December compares reasonably well with our figure of 195kWh for December from a smaller system. I know for sure that we have loads of days in winter when we struggle to get above about 500W all day, so using the ratio of December generation for the two systems I would say that you will have lots of winter days when you struggle to get above about 1kW. I think 2kW is very much a pipe dream for any sort of guaranteed output in winter, TBH. May be some days in winter when you see way more than 1kW, but equally there will be days when you probably see less. The ratio between good and bad days can easily be three or four to one in terms of output. For example our best summer day can deliver around 40kWh, but we can easily get days like one last week where we only generated around 9kWh. Same applies in winter, but with levels that are around one quarter of those in midsummer.

I think from your clear ''at the coal face'' experience shows a good argument for battery storage so that at least what you get is useable even if stored in a battery for use later rather than fed to the grid.

Battery storage makes a huge difference. Not just the obvious one of being able to use more PV generated electricity overall, but the unexpected benefit (to me) of having a system that meets short duration peak power requirements on dull or cloudy days, with the battery topping up again when the generation spikes upwards. This means that we can use the washing machine, dishwasher etc more or less irrespective of whether there is enough peak PV generation, knowing that the battery will soak up the peak power demand and the lower power from the PV will top the battery back up again over a period of time. The battery system works like a buffer, giving us a "no grid" peak power capability of the PV power output plus the battery inverter max power.

[nowty]

Battery storage makes a huge difference. Not just the obvious one of being able to use more PV generated electricity overall, but the unexpected benefit (to me) of having a system that meets short duration peak power requirements on dull or cloudy days, with the battery topping up again when the generation spikes upwards. This means that we can use the washing machine, dishwasher etc more or less irrespective of whether there is enough peak PV generation, knowing that the battery will soak up the peak power demand and the lower power from the PV will top the battery back up again over a period of time. The battery system works like a buffer, giving us a "no grid" peak power capability of the PV power output plus the battery inverter max power.

A Nowty Towers extreme example of Oldgreybeard's point,

[Adokforme]

In our case it's a godsend, not only has our inverter thrown up an error message resulting in zero energy generation from PV but with WT1 down also battery storage is our one remaining saviour. At least allowing us run on Go's cheap rate overnight leccy!

[Joeboy]

In our case it's a godsend, not only has our inverter thrown up an error message resulting in zero energy generation from PV but with WT1 down also battery storage is our one remaining saviour. At least allowing us run on Go's cheap rate overnight leccy!

Nice one, a fallback for a fallback. A man after my own heart.

We have had and will continue to haves seamless days of rain, now Utilising the grid and our storage capacity to keep it all low cost & Green.