31% PV efficency

[Joeboy]

https://www.nature.com/articles/s41565-022-01228-8

A long way to go before production but it's good to see.

[Stinsy]

We really are at the stage where solar technology is mature. Currently 20% efficiency is normal, I can see 25% being normal on commercial products in my lifetime. Prices are already super-cheap too.

[Mart]

Not much that gets me more excited than the potential for silicon/perovskite PV. Been watching the numbers rise steadily for years, and I think figures in the mid to high %30's is reasonably expected. [Sorry if that's covered in the report, I quickly ran out of talent trying to read it.]

Crucially, as Perovskite is so cheap, if all of the issues can be worked out, then even with the added complexities of combining two chemistries, the panels should only cost the same per Wp as Silicon panels. Eg a 400Wp Si panel may cost £200, and a 600Wp Si/Perovskite panel may cost £300.

What excites me so much about the efficiency and cost, is that you get to put so much more generating power on a roof, or a field, for the same land cost, and also most of the non-PV costs will be the same (frames, rails, cables, labour etc). I think the PV costs for a PV farm are about 30% of the total cost, so if for example you could put twice as much MWp in the space, then the PV cost doubles, but most other costs don't change much, so 200% the generation for 130% of the cost.

For demand side, it means more energy from the same roof area, more viability for shaded roofs, small rooves etc etc.. For demand side roof top PV, I believe the PV is about 50% of the cost, so a doubling (again just as an example) would cost 150%. However, these costs were before the World went mad and inflation impacted all costs especially labour, so take with a pinch of salt.

Lastly for my own ponderings, I have 5.58kWp on my roofs with ~15% efficient panels, so at 35% the potential rises to 13kWp, and a big NO from the DNO, but fascinating to put it all into context.

[AE-NMidlands]

Lastly for my own ponderings, I have 5.58kWp on my roofs with ~15% efficient panels, so at 35% the potential rises to 13kWp, and a big NO from the DNO, but fascinating to put it all into context.

But if you had batteries and didn't try to export any more than now, why should it affect the DNO?
A

[Oldgreybeard]

Even without batteries it would only be a problem if the inverter was uprated to match the higher output. There's merit in having panels that are rated for a fair bit more than the inverter maximum output, as long as the input limits are met, as this will tend to flatten the generation peak and give more power at either end of the generation period each day.

If my system hadn't been on a reasonably good FiT deal then when expanding it I'd have looked at just adding more panels whilst keeping the same inverter rating, really just to get that benefit during the majority of the time when the system isn't running at its maximum power.

[Mart]

Lastly for my own ponderings, I have 5.58kWp on my roofs with ~15% efficient panels, so at 35% the potential rises to 13kWp, and a big NO from the DNO, but fascinating to put it all into context.

But if you had batteries and didn't try to export any more than now, why should it affect the DNO?
A

I don't know, why should it affect the DNO if I had batteries and didn't try to export any more?

[AE-NMidlands]

Lastly for my own ponderings, I have 5.58kWp on my roofs with ~15% efficient panels, so at 35% the potential rises to 13kWp, and a big NO from the DNO, but fascinating to put it all into context.

But if you had batteries and didn't try to export any more than now, why should it affect the DNO?
A

I don't know, why should it affect the DNO if I had batteries and didn't try to export any more?

You said

a big NO from the DNO,

so I interpreted that as them having a veto on what you did to upgrade your system behind the inverter.

[Mart]

But if you had batteries and didn't try to export any more than now, why should it affect the DNO?
A

I don't know, why should it affect the DNO if I had batteries and didn't try to export any more?

You said

a big NO from the DNO,

so I interpreted that as them having a veto on what you did to upgrade your system behind the inverter.

Nope. I was simply chatting about how much more PV could be fitted to a given space. I added the comment about the DNO, in case anyone with an anorak and an adenoids problem got petty and pointed out that a house can't normally have 13kWp of PV.

But back to your question, as I didn't raise batteries or export limitation, (you did), why should it affect the DNO?

[Stinsy]

Common misconception!

DNO cares only about inverter power. You can have as much solar as you like!

[Mart]

Common misconception!

DNO cares only about inverter power. You can have as much solar as you like!

I appreciate this is a further digression from the OP, but on that subject, I'm still hoping to add some more PV (steep pitched south facing for winter gen), via a zero export battery addition. Been chatting with a company, and the use or not of the PV input (hybrid inverter but not linked to my existing PV) may not be an issue. But my gut tells me that the DNO may still get funny, even if the PV isn't mentioned*, as they've already said my current 5.9kW limit shouldn't have been granted.

So I have to gamble on rockin the boat, with a battery application, even if it's zero export.

Difficult decision. Probably end up tossing a coin.


*Anyone know if you need to tell the DNO about PV that feeds into a battery, for domestic consumption? I can see why it might be irrelevant, but at the same time it's grid connected ..... sorta? [Edit - Just to be clear, a battery whose inverter has DNO certification confirming it meets the zero export requirements.]