Solar PV (1 Viewer)

[Anthony]

The app we use requires a newer phone than mine so my wife gets all the stats. Although do know that today was the first day we took in WAY more than we used.
Not surprised.... scorchio!

 

[pete]

This is right now.

 

[Anthony]

This was today. Red is imported and yellow is exported (sold).
Also worth remembering that this is peak sun.

 

[pete]

This was today. Red is imported and yellow is exported (sold).
Also worth remembering that this is peak sun.

View attachment 17183

is that saying you exported 17.1kWh, imported 1.4kWh, and used nothing that you generated?

 

[pete]

So I set up the PV battery to charge itself from the grid between 2am-4am (cheapest 12c smart meter tariff time), which it did. I also have the car set to start charging at 2am, which it also did.

As soon as it hit 4am, the car started charging from the house battery instead of the grid, which is exactly what you’d expect to happen & means I saved some money because it was using the cheapest rate power I’d put into the PV battery instead of the overnight 22c rate BUT it would make more sense to not do that - pay the 4am-7am 22c rate for the car and keep the PV battery for use after 7am, when the 42c daytime rate kicks in.

Right?

This is all making me think I should have another battery.

 

[ernesto]

So I set up the PV battery to charge itself from the grid between 2am-4am (cheapest 12c smart meter tariff time), which it did. I also have the car set to start charging at 2am, which it also did.

As soon as it hit 4am, the car started charging from the house battery instead of the grid, which is exactly what you’d expect to happen & means I saved some money because it was using the cheapest rate power I’d put into the PV battery instead of the overnight 22c rate BUT it would make more sense to not do that - pay the 4am-7am 22c rate for the car and keep the PV battery for use after 7am, when the 42c daytime rate kicks in.

Right?

This is all making me think I should have another battery.

Sounds like it's programmable and you don't need another battery

 

[Anthony]

is that saying you exported 17.1kWh, imported 1.4kWh, and used nothing that you generated?

I think the negative spikes in the export is where we were using power. So less was being exported but we still weren't using enough to start importing.
It was an unusual day anyway. I was sitting outside all day. The only electric being used was the usual "always on" things life router and fridge. Probably one one computer going.

 

[pete]

So I set up the PV battery to charge itself from the grid between 2am-4am (cheapest 12c smart meter tariff time), which it did. I also have the car set to start charging at 2am, which it also did.


Sounds like it's programmable and you don't need another battery

The inverter has been programmed to charge the battery between those hours alright but I’m not sure how to program it to not draw from the battery between 4am-7am.

 

[pete]

I think the negative spikes in the export is where we were using power. So less was being exported but we still weren't using enough to start importing.
It was an unusual day anyway. I was sitting outside all day. The only electric being used was the usual "always on" things life router and fridge. Probably one one computer going.

Bit odd that the top graph shows some green but a figure of 0%

 

[Anthony]

So I set up the PV battery to charge itself from the grid between 2am-4am (cheapest 12c smart meter tariff time), which it did. I also have the car set to start charging at 2am, which it also did.

As soon as it hit 4am, the car started charging from the house battery instead of the grid, which is exactly what you’d expect to happen & means I saved some money because it was using the cheapest rate power I’d put into the PV battery instead of the overnight 22c rate BUT it would make more sense to not do that - pay the 4am-7am 22c rate for the car and keep the PV battery for use after 7am, when the 42c daytime rate kicks in.

Right?

This is all making me think I should have another battery.

I think you're correct. Charge the car at the night rate and use the battery to cook the dinner.
We're experimenting with only charging the car between 2 and 4. Perfect for when my wife has a day off and we can charge 2x 2 hours at cheap rate rather than 2 hours cheap and 2 hours night rate.

Once you get into this shit you go crazy with it. For example we don't use the electric shower anymore (once we saw how much it cost) we use the one connected to the hot water tank that uses a pump. It's generally free.

 

[Anthony]

Bit odd that the top graph shows some green but a figure of 0%

Yea the app give you tons of data, not sure what all of it means.

 

[pete]

I think you're correct. Charge the car at the night rate and use the battery to cook the dinner.
We're experimenting with only charging the car between 2 and 4. Perfect for when my wife has a day off and we can charge 2x 2 hours at cheap rate rather than 2 hours cheap and 2 hours night rate.

Once you get into this shit you go crazy with it. For example we don't use the electric shower anymore (once we saw how much it cost) we use the one connected to the hot water tank that uses a pump. It's generally free.

Yeah I’m not charging the car tonight so we can see exactly how having the PV battery charged for 2 hours overnight works out.

Just trying to set it up to minimise export as much as possible. We were out yesterday afternoon and it generated a rake of power that went straight into the grid.

 

[Anthony]

Yeah I’m not charging the car tonight so we can see exactly how having the PV battery charged for 2 hours overnight works out.

Just trying to set it up to minimise export as much as possible. We were out yesterday afternoon and it generated a rake of power that went straight into the grid.

Did your installer fill out the form ( M Something) to submit to your provider. It tells Electric Ireland (or whoever) to pay you for the exported power. It comes off your bill.

The goal is to sell enough power to offset the standing charges.

 

[pete]

Did your installer fill out the form ( M Something) to submit to your provider. It tells Electric Ireland (or whoever) to pay you for the exported power. It comes off your bill.

The goal is to sell enough power to offset the standing charges.

Yeah, waiting for all that to kick in now.

 

[Anthony]

Yeah, waiting for all that to kick in now.

It'll take at least a month, maybe 2.

 

[snakybus]

Solar Electricity Grants

Use solar electricity to generate renewable electricity for your home.

www.seai.ie

Grants available. If you root around that site you'll see an elearning module on Solar PV what I worked on and all.

 

[pete]

The inverter has been programmed to charge the battery between those hours alright but I’m not sure how to program it to not draw from the battery between 4am-7am.

So I don’t think this can be done but I’m trying a slightly different approach.

- leave the car battery charging from 2am until it’s full, so 2 hours at 12.25c per kWh and the rest at 20.86c per kWh

- I’ve told the inverter to charge the PV battery from 2am - 7:59am. This should (I think) mean it will fully charge, and then won’t discharge, for those 6 hours.

If I’ve got this right, then at 8am the PV battery should be 100% charged so we don’t pay the peak 42.3c rate until its drained again, by which time we should be getting some solar pv power anyway… in theory.

Right?

edit: this is the Solis inverter config

 

[Anthony]

Can you tell the inverter to charge the battery from 2 am - 4 am then top it up with solar?

 

[pete]

Can you tell the inverter to charge the battery from 2 am - 4 am then top it up with solar?

Yeah that’s what I was aiming for, with the intention being we’d have a fully charged battery when we get up and before the solar starts generating. But if the car is still charging after 4am it immediately starts using the PV battery charge instead of the grid.

 

[pete]

Here’s yesterday’s stats anyway


That blue chunk of export is annoying me. Having another 5kwh battery would probably get rid of the ~30% export/import discrepancy, but that’s in absolutely optimal conditions. Having the extra battery to fill up at overnight cheap rate could also be useful in the depths of winter when the PV isn’t generating much, but I’ll wait and see.

Still waiting on the other 3 panels to be hooked up properly…