Solar panels and battery - any real world recommendations?
- Thread starter GinG
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Damn. Was hoping it would be live data or something with the Octopus mini.
Yeah I see that. Had the negative figure from ages ago. I just expected more info, like a graph or something. Would be nice to see live date of how much exported at any given point for example.
Could be it will happen in the next few days. I only just got the email saying it is live in the morning.
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Only if your smart meter supports it.
I’m exporting 5.4kw right now but my min is reporting 0w. My half hourly reads show up 24 hours later.
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From my perspective, I was paying over £250 DD per month. I now pay £50-75 per month and am around £500 in credit. 3 years of ownership (thereabouts), 36 months x (250-75) = £6,300 in direct debit saving + £500 credit, that's nearly £7k. that DD includes gas too though. I paid around 11k I think at the time, so another 12-18 months all things being equal and I am basically quids in, and I don't worry so much about using electricity now thanks to also having a battery.
Same here, my meter doesn't support live export power, currently exporting 5.7kW and the Mini shows 0. I just use the inverter grid power for live data.
Amazing!
If it was me running Octopus export department, I wouldn't hurry too much with the permission to export
91kw is massive, which direction are the panels facing?
How much did it cost? My guess is £21,600.
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Was a bit more then that to install at £26k. The install is a bit more complicated than most though with the armoured cables runs to the garage and consumer unit. I knew that when purchasing though.Amazing!
If it was me running Octopus export department, I wouldn't hurry too much with the permission to export
91kw is massive, which direction are the panels facing?
How much did it cost? My guess is £21,600.
Generated 94.7 KW today and have DNO agreement for 10kw export once I have my MCS.
The roof is at 220 degrees(SW) with all panels on the one roof.
BTW did you check how they connected the panels to the Powerwalls?
Probably for maximum efficiency you want 6 strings with 5 or 6 panels each.
Many installers like to save cable and work and use fewer strings than optimal.
If you took a picture with the front cover removed, you can see how the DC string cables are connected - they are the in right upper corner, there are 6 connectors for 3 strings.
Probably for maximum efficiency you want 6 strings with 5 or 6 panels each.
Many installers like to save cable and work and use fewer strings than optimal.
If you took a picture with the front cover removed, you can see how the DC string cables are connected - they are the in right upper corner, there are 6 connectors for 3 strings.
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You are robbing your energy supplier in plain day light
If you have panels and battery, you should look into getting a heat pump and cutting the gas off. Octopus Energy have 15% off this summer and the Heat Geak guys have 500 quid discount.
They connected three strings, two with ten panels and one with 11 all into the 3 MPPT on one Powerwall which I was ok with as the one inverter can deal with 21kw of DC. The other power wall charges on AC so I can charge at 10kw into the batteries. A powerwall and DC expansion can only charge at 8kw.
There are no shading issues with my house roof and the other powerwall gives me the ability to add more solar onto the garage roof where the batteries are located if needed.
Are the Powerwalls installed next to each other?
I'm no expert, but IHMO you should move the 11 panel string to the 2nd Powerwall. It will put less load on the inverter in the 1st one - so it will last longer. And it will avoid two conversions, that loose energy - currently 1st Powerwall converts DC to AC, and the 2nd one AC to DC to charge the battery. Instead you can have the 11 panels feed DC directly to the battery. That may not matter much right now, if you don't have a heat pump - as you'll be selling all the generated energy to the grid, rather than charge the battery.
I'm no expert, but IHMO you should move the 11 panel string to the 2nd Powerwall. It will put less load on the inverter in the 1st one - so it will last longer. And it will avoid two conversions, that loose energy - currently 1st Powerwall converts DC to AC, and the 2nd one AC to DC to charge the battery. Instead you can have the 11 panels feed DC directly to the battery. That may not matter much right now, if you don't have a heat pump - as you'll be selling all the generated energy to the grid, rather than charge the battery.
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That's certainly something to think about. Does the installer need to configure the powerwall MPPT or would it be a matter of turning off and removing the string and just connecting to the other powerwall and powering both back up?
To the DNO for another G99 as Im replacing my 5kW inverter in the loft with a 10.5kW one in the garage. The south-east strings will be on two MPPTs and two lots of 3kW of new panels facing north-east and south-west on another MPPT each. I specifically requested a large inverter now we have a heat pump and induction hob as we can really draw some juice. The batteries are quite old now, but can max out that 10.5kW as they're high voltage (427v if I go to eight modules, which i will for 19.6kWh total) and can discharge at up to 48A (20kW!).
My previous installer said I was given no limit on the G99. I took that to mean they were happy with 5kW + 3.68kW so it would be no issue, but my new installer thinks they've fudged it. Either way, I may get hit with a stricter limit this time as Northern power are notoriously stingy with export limits. Im hoping as we're on a newer estate it might not be too bad. If I get at least 6-7kW I can make that work.
My previous installer said I was given no limit on the G99. I took that to mean they were happy with 5kW + 3.68kW so it would be no issue, but my new installer thinks they've fudged it. Either way, I may get hit with a stricter limit this time as Northern power are notoriously stingy with export limits. Im hoping as we're on a newer estate it might not be too bad. If I get at least 6-7kW I can make that work.
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