With BST approaching what's the collective view on overnight battery charging?

[Giller]

Would like to pick the hive mind if I may, we installed solar May last year, switched to a Zappi in September from a conventional charger so we could use surplus solar during the day, being in Northern Ireland limited energy companies and no smart tariffs, over the winter have been charging the 10.2 Kw battery at the cheaper night time rate, but is it time to stop this to maximise battery charging during the day from the solar?

 

[Bam Bam]

Would like to pick the hive mind if I may, we installed solar May last year, switched to a Zappi in September from a conventional charger so we could use surplus solar during the day, being in Northern Ireland limited energy companies and no smart tariffs, over the winter have been charging the 10.2 Kw battery at the cheaper night time rate, but is it time to stop this to maximise battery charging during the day from the solar?

So is the old 'when do we switch from winter to solar tariff' conundrum?

Or just 'when to change the charging strategy'?

Not sure I've understood the paramaters.

What is the cost for overnight and what do you receive for solar export?

 

[Giller]

So is the old 'when do we switch from winter to solar tariff' conundrum?

Or just 'when to change the charging strategy'?

Not sure I've understood the paramaters.

What is the cost for overnight and what do you receive for solar export?

Being new to solar don't know what the old conundrum is exactly, hence potential issues with the parameters, hence picking the brains of those who've experience.

Over here only 2 companies purchase surplus, fortunately I'm with the one who pays the top rate of 0.139 per Kw and has a night rate of 0.1389 per Kw.

 

[Bam Bam]

Being new to solar don't know what the old conundrum is exactly, hence potential issues with the parameters, hence picking the brains of those who've experience.

For me in Jolly old England Octopus offer an EV tariff which is good in the winter (cheap overnight to fill the batteries) and Intelligent Flux which is good in Summer (fantastic export rates, but not cheap overnight).

Over here only 2 companies purchase surplus,

It sounds like you've got much less choice so you're stuck with what you've got.

I'm with the one who pays the top rate of 0.139 per Kw and has a night rate of 0.1389 per Kw.

Wow, so it is basically the same.

I'm guessing the main thing will be to make sure you don't deplete your battery and run out in the evening.

In that case, using solar OR filling up at night seem to be essentially equivalent for you.

If I've interpreted that correctly then you don't have much to worry about.

Perhaps the overnight filling is safer in case there is a really cloudy day and you don't fill the battery to get you through.

Conversion losses?

One further thought...

Do you have a hybrid inverter? In that case filling up from the solar might be more efficient as you only one get one set of AC-DC losses. If you've got an AC-coupled battery then I don't think it will make a difference.

 

[Giller]

For me in Jolly old England Octopus offer an EV tariff which is good in the winter (cheap overnight to fill the batteries) and Intelligent Flux which is good in Summer (fantastic export rates, but not cheap overnight).

Please don't, I've seen their tariffs, pass a box of tissues.....

It sounds like you've got much less choice so you're stuck with what you've got.

Pretty much, I got involved with a relatively new supplier called Share Energy over here, heard a rumour they were going to purchase surplus and got my foot in the door early, basically paying 30% more than the only other purchaser, and I loved the simplicity of the export rate pretty much equaling the night rate.

Conversion losses?

One further thought...

Do you have a hybrid inverter? In that case filling up from the solar might be more efficient as you only one get one set of AC-DC losses. If you've got an AC-coupled battery then I don't think it will make a difference.

Have a Solis 6 hybrid 3.68kWh inverter linked to a Dyness Powerbox Pro 10.24 kWh battery, 12 panels facing SE so more capacity than inverter, but in NI with our grid infrastructure we can't have more than 3.68, still works very well.

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[Rolfe]

I think the issue is that the best tariffs aren't available in Northern Ireland, and it might be better to put the excess solar in the car. Is that right?

 

[Giller]

I think the issue is that the best tariffs aren't available in Northern Ireland, and it might be better to put the excess solar in the car. Is that right?

Actually, that’s what I was thinking, much appreciated.

 

[Bam Bam]

Please don't, I've seen their tariffs, pass a box of tissues.....

Pretty much, I got involved with a relatively new supplier called Share Energy over here, heard a rumour they were going to purchase surplus and got my foot in the door early, basically paying 30% more than the only other purchaser, and I loved the simplicity of the export rate pretty much equaling the night rate.

At least you're getting more for export than we are on the big island with Octopus.

Have a Solis 6 hybrid 3.68kWh inverter linked to a Dyness Powerbox Pro 10.24 kWh battery, 12 panels facing SE so more capacity than inverter, but in NI with our grid infrastructure we can't have more than 3.68, still works very well.

Hmmm, if I've understood correctly that you've got a DC coupled inverter then there is a case for having your battery empty before you get the sun. The battery can absorb the excess that you are unable to export, until it is full.