Inverter efficiency: What you say at 3:00 is incorrect (and it contradicts your graphic). Tesla's datasheet and your graphic give the round trip efficiency for the PW3 as 89% whereas the 97.5% you talk of is for a one-way DC-AC conversion at the inverter's peak efficiency (which won't ever be realised in installations with mismatched array output & inverter rating). It's a pity you don't talk about inverter efficiency curves and starting voltages (which are HIGHLY relevant for shorter strings, which the unwary may be tempted by with more MPPT available).
Hi, thanks for the comment. You are correct, 97.5% is the DC-AC conversion, not the round trip efficiency. We realised the mistake when editing the video and it was too late to change it. Hence why the graphic is correct. There should also have been an asterisk to highlight the correction, or it should have been cut out of the video. Thank you for pointing this out. I’ve pinned the comment. We will make a video on the inverter efficiency curves shortly. -Tok
@@spiritenergy_uk Bravo! - I look forward to this - it is a topic I think is insufficiently exposed (by manufacturers) and is consequently insufficiently understood and insufficiently discussed.
@@falfield yes most people just aren’t looking for that level of detail. But it’s good to explore it. You clearly know your stuff when it comes to solar!
@@spiritenergy_uk You're right of course that most people don't seek this detail, but in part that's because they've no idea it is pertinent. And why is that? Partly because manufacturers aren't routinely publishing the info and it is only to be found in research & academic texts. So whether or not you've managed to extract it all from Tesla (and kudos to you if you have) I REALLY hope you'll set out the PW3 efficiency curves at the various inverter power settings and/or show how HUGELY relevant this & starting voltage is when considering a small number of extra panels on an additional roof slope. Inverter efficiency at 20% power output (or min. power for 90/95% efficiency) should be obligatory for every datasheet.
I chose PW3, and am awaiting an installation date with 11 panels over 3 roof directions benefitting from the 3 separate MPPTs for these. One face is NE, so keen to see separately how that performs as some installers wouldn't install there. I chose one who said what they 'would' do, rather than what they 'would not' do. As the Customer, it was my decision to invest in NE panels, even though they could produce less than conventionally directed panels - you make your choice with your eyes open! While the installers are there, the additional cost is reasonable.
Thanks for the comment. This is completely correct, if you’re already on site then it is not a huge additional cost to add on other roof faces - especially if you don’t need an additional inverter as a result of getting PW3. I’d expect the NE roof to generate ~30% less than a perfect S roof would. Will be interesting to see, please let me know how it does perform in the end. - Tok
@@spiritenergy_uk I'll certainly publish my findings. Installation is nominally October, so I'll be stepping into the poorer season - so every little helps. I'm also considering the additional battery extension when it comes out - any idea when it's due? Tesla say 'the autumn' - which could mean pretty much anything!!
At least you'll beat the energy price hike scheduled for October! Regarding the battery expansion packs, we don't have any more information than what Tesla has announced publicly, I'm afraid. Best of luck with your installation. -Luke
@@spiritenergy_uk Thanks for that - I guess they want PW3 out and running before starting to issue the expansion units. And I beat the price rise by fixing in March (Octopus) and not bothering with the summer drop which was pointless as I wouldn't use much then... We know October will likely hike it up again! Fixing the gas in March was the best deal!
@@spiritenergy_uk Hi… I’ve just had a reply from my installers who have spoken with Tesla. Tesla are expecting mid-Q1 2025 for the expansion pack in the UK. So I’ll have to wait!
Enjoyed the video and very informative thank you . Just one bit of valuable information you didn't touch on is the start up voltage for the solar is (60volts min on the Tesla) and (150 volts on the give energy) for me the set up I'm looking to get ,on one string that i would have is very important as i only have 4 solar panels so the Tesla will start making energy earlier in the day as well as on cloudy days the give energy might not make use at all vs the Tesla. What are your thoughts on this ? Thanks Marc
Thanks for the comment! Yes, both batteries will be able to keep the solar running and power the house in an outage. The solar will also be able to charge the battery in a power cut if there is excess generation. -Tok
Thanks for the comment. Yes, please drop me an email to tokc@spiritenergy.co.uk. We’ve installed a few without solar that are going to save money via off-peak arbitrage. -Tok
Can battery systems be moved if you move house/is it cost effective with labour costs? I believe with solar panels, they lose their some sort of certification if they get taken off the roof. Is this the same,e with batteries?
Thanks for the comment. Solar panels may lose their warranties if moved. This is also the case for most battery systems I believe. It’s usually not worth it, and you should just get a new one at the new house. You may be able to add the NPV of the battery onto the house price if you can convince the buyer of how much they’ll save as a result of the system. This is what you can often do with solar PV systems. Although this topic is quite heavily debated. This article might help… blog.spiritenergy.co.uk/homeowner/unleashing-your-brightest-investment-the-profit-of-solar-power?hs_amp=true Tok
My supplier is recommending 2 x 5kWH enphase units, whereas I don’t understand why one of the 13.5kWH AIO units doesn’t offer a significantly better economy/storage kWH. I’m putting in enphase micro inverters and 16 PV units at the sam3 time (we have tree shading issues). Am I right or am I missing something please?
Thanks for the question. I agree with you - the economics of the AIO tend to be better than the Enphase so it’s worth going back to them on that. I’d also ask them to run through the maths that shows the micro-inverters are actually worth doing as well. Is the 25-yr increase in savings actually going to be higher than the cost? In my experience it rarely is. AC coupled systems also have losses because they need to invert the current so much. A DC coupled system sounds like the best thing for this in my experience. Maybe a PW3 with the extra MPPT to help mitigate shade. -Tok
@@spiritenergy_uk Thank you. My only concern with the PW3 is that it isn’t included in the beta octopus intelligent flux scheme, whereas the AIO is. Which is odd, because octopus fit the PW3 and enphase, but not AIO.
@@yp77738yp77739 We were told by Tesla when they came to our office in Reading that it will be compatible with Octopus Intelligent Tariffs, so hopefully in the pipeline for release soon. -Tok
@@spiritenergy_uk Hmmn. I would say that if a 2 MPPT installation underperforms because of shade, then a third MPPT isn't going to rescue the situation. The key fact behind this is the impossibility of ensuring that all shaded panels are at all times grouped together, and are equally impaired. Worse, doing away with the microinverters as you suggest will lose him individual panel level monitoring (Tesla doesn't know individual panel-level data and doesn't offer consumer access to individual string performance). So for variable soft (tree) shading, I'm puzzled you are not mentioning DC optimisers or the groundbreaking AIKO panels with partial cell-level optimisation.
@@falfield Thanks for the comment. We have found that third MPPT does really help the situation and you often get shade scenarios where a consistent bank of panels will be affected. Video out this week with a good example case study. I’ll link it here when it’s launched. In that case, the system with PW3 inverter would have a yield reduction due to shading of 7.6%. With Enphase it would be 5.3%. Due to the high uplift for Enphase kit it proved to be not cost effective. In that case study we then go onto talk about how we took the bypass diode layout and half cell orientation into account. That particular customer had JA440 panels, however, we now recommend AIKO as you say. Panel level monitoring is a nice perk but we find a lot of clients don’t care. The panels themselves break incredibly rarely. Far less often than the optimisers or microinverters. We try not to push them on people unless the data shows it’s worth it. Which it rarely is. For this particular comment, we would have to take a detailed look at the roof and situation. But there’s only so much that one can say in a TH-cam comment without proper data… Thank you for your technical questions and for watching the channel. -Tok
For more detail, and for the full table comparing GivEnergy All in One and Tesla Powerwall 3, check out our article here: blog.spiritenergy.co.uk/homeowner/all-in-one-vs-tesla-powerwall-3
I think some of the data given regarding the AIO is incorrect, for example the Giv Gateway is rated at 100A not 80A (according to the datasheet). In addition the DNO limit relating to the AIO inverter added to any Solav PV inverter doesn't seem right. I have a DNO export limit of 4kW which is addressed by limiting the export from the gateway. I never get 4kW solar so maybe I'm misunderstanding the video. Maybe for export purposes the video assumes a stand-alone AIO?
Hi Nigel, Thank you for the comment. The grid supply connection to the Giv Gateway can be rated up to 100A (protected by 100A MCB), but the load output connection is only rated up to 80A (protected by 80A MCB), and so the Gateway effectively limits your backup load supply to 80A. Ergo, it can only backup 80A. The information is a bit obscure, and the datasheet doesn't make it clear. We were referencing the installation manual along with our own experience. Here's a link to the installation manual; see page 29, breaker D. givenergy.co.uk/wp-content/uploads/UK-Installation-Manual-All-in-One.pdf Regarding the DNO limitations, the video is correct. If you have a 6kW GivEnergy All in One and a 4kW solar inverter, you'd need to apply for 10kW of DNO permission. In your case, it sounds as though the DNO limited you to 4 kW, meaning you could not export your full potential-only 40% of it. -Luke
Inverter efficiency: What you say at 3:00 is incorrect (and it contradicts your graphic). Tesla's datasheet and your graphic give the round trip efficiency for the PW3 as 89% whereas the 97.5% you talk of is for a one-way DC-AC conversion at the inverter's peak efficiency (which won't ever be realised in installations with mismatched array output & inverter rating).
It's a pity you don't talk about inverter efficiency curves and starting voltages (which are HIGHLY relevant for shorter strings, which the unwary may be tempted by with more MPPT available).
Hi, thanks for the comment. You are correct, 97.5% is the DC-AC conversion, not the round trip efficiency. We realised the mistake when editing the video and it was too late to change it. Hence why the graphic is correct. There should also have been an asterisk to highlight the correction, or it should have been cut out of the video. Thank you for pointing this out. I’ve pinned the comment.
We will make a video on the inverter efficiency curves shortly.
-Tok
@@spiritenergy_uk Bravo! - I look forward to this - it is a topic I think is insufficiently exposed (by manufacturers) and is consequently insufficiently understood and insufficiently discussed.
@@falfield yes most people just aren’t looking for that level of detail. But it’s good to explore it. You clearly know your stuff when it comes to solar!
@@spiritenergy_uk You're right of course that most people don't seek this detail, but in part that's because they've no idea it is pertinent. And why is that? Partly because manufacturers aren't routinely publishing the info and it is only to be found in research & academic texts. So whether or not you've managed to extract it all from Tesla (and kudos to you if you have) I REALLY hope you'll set out the PW3 efficiency curves at the various inverter power settings and/or show how HUGELY relevant this & starting voltage is when considering a small number of extra panels on an additional roof slope. Inverter efficiency at 20% power output (or min. power for 90/95% efficiency) should be obligatory for every datasheet.
Great to see quality brands being discussed (vs. the cheap Chinese brands)!
I chose PW3, and am awaiting an installation date with 11 panels over 3 roof directions benefitting from the 3 separate MPPTs for these. One face is NE, so keen to see separately how that performs as some installers wouldn't install there. I chose one who said what they 'would' do, rather than what they 'would not' do.
As the Customer, it was my decision to invest in NE panels, even though they could produce less than conventionally directed panels - you make your choice with your eyes open! While the installers are there, the additional cost is reasonable.
Thanks for the comment. This is completely correct, if you’re already on site then it is not a huge additional cost to add on other roof faces - especially if you don’t need an additional inverter as a result of getting PW3.
I’d expect the NE roof to generate ~30% less than a perfect S roof would. Will be interesting to see, please let me know how it does perform in the end.
- Tok
@@spiritenergy_uk I'll certainly publish my findings. Installation is nominally October, so I'll be stepping into the poorer season - so every little helps.
I'm also considering the additional battery extension when it comes out - any idea when it's due? Tesla say 'the autumn' - which could mean pretty much anything!!
At least you'll beat the energy price hike scheduled for October!
Regarding the battery expansion packs, we don't have any more information than what Tesla has announced publicly, I'm afraid.
Best of luck with your installation.
-Luke
@@spiritenergy_uk Thanks for that - I guess they want PW3 out and running before starting to issue the expansion units.
And I beat the price rise by fixing in March (Octopus) and not bothering with the summer drop which was pointless as I wouldn't use much then... We know October will likely hike it up again! Fixing the gas in March was the best deal!
@@spiritenergy_uk Hi…
I’ve just had a reply from my installers who have spoken with Tesla.
Tesla are expecting mid-Q1 2025 for the expansion pack in the UK. So I’ll have to wait!
Hey Tok, really nice video - well done
Thank you sir! -Tok
Enjoyed the video and very informative thank you .
Just one bit of valuable information you didn't touch on is the start up voltage for the solar is (60volts min on the Tesla) and (150 volts on the give energy) for me the set up I'm looking to get ,on one string that i would have is very important as i only have 4 solar panels so the Tesla will start making energy earlier in the day as well as on cloudy days the give energy might not make use at all vs the Tesla.
What are your thoughts on this ?
Thanks Marc
Would like to see a comparison between the Powerwall 3 and the new Sigenergy AIO.
Good vid 👍
Very detailed video, thank you.
Would Tesla Powerwall 3 charge from solar while powering the house during the power cut?
Thanks
Thanks for the comment! Yes, both batteries will be able to keep the solar running and power the house in an outage. The solar will also be able to charge the battery in a power cut if there is excess generation.
-Tok
Great video, I’m thinking on getting a Powerwall 3 and charging on cheap rate at 7p kWh. Would you advise on this without solar?
Thanks for the comment. Yes, please drop me an email to tokc@spiritenergy.co.uk.
We’ve installed a few without solar that are going to save money via off-peak arbitrage.
-Tok
Can battery systems be moved if you move house/is it cost effective with labour costs? I believe with solar panels, they lose their some sort of certification if they get taken off the roof. Is this the same,e with batteries?
Thanks for the comment. Solar panels may lose their warranties if moved. This is also the case for most battery systems I believe.
It’s usually not worth it, and you should just get a new one at the new house.
You may be able to add the NPV of the battery onto the house price if you can convince the buyer of how much they’ll save as a result of the system. This is what you can often do with solar PV systems. Although this topic is quite heavily debated. This article might help… blog.spiritenergy.co.uk/homeowner/unleashing-your-brightest-investment-the-profit-of-solar-power?hs_amp=true
Tok
Would love to hear your thoughts on Enphase’s IQ Battery..
Noted! I'll add it to the drawing board.
Thanks for the comment,
-Luke
My supplier is recommending 2 x 5kWH enphase units, whereas I don’t understand why one of the 13.5kWH AIO units doesn’t offer a significantly better economy/storage kWH. I’m putting in enphase micro inverters and 16 PV units at the sam3 time (we have tree shading issues). Am I right or am I missing something please?
Thanks for the question.
I agree with you - the economics of the AIO tend to be better than the Enphase so it’s worth going back to them on that.
I’d also ask them to run through the maths that shows the micro-inverters are actually worth doing as well. Is the 25-yr increase in savings actually going to be higher than the cost? In my experience it rarely is.
AC coupled systems also have losses because they need to invert the current so much. A DC coupled system sounds like the best thing for this in my experience. Maybe a PW3 with the extra MPPT to help mitigate shade.
-Tok
@@spiritenergy_uk Thank you.
My only concern with the PW3 is that it isn’t included in the beta octopus intelligent flux scheme, whereas the AIO is. Which is odd, because octopus fit the PW3 and enphase, but not AIO.
@@yp77738yp77739 We were told by Tesla when they came to our office in Reading that it will be compatible with Octopus Intelligent Tariffs, so hopefully in the pipeline for release soon.
-Tok
@@spiritenergy_uk Hmmn. I would say that if a 2 MPPT installation underperforms because of shade, then a third MPPT isn't going to rescue the situation. The key fact behind this is the impossibility of ensuring that all shaded panels are at all times grouped together, and are equally impaired. Worse, doing away with the microinverters as you suggest will lose him individual panel level monitoring (Tesla doesn't know individual panel-level data and doesn't offer consumer access to individual string performance). So for variable soft (tree) shading, I'm puzzled you are not mentioning DC optimisers or the groundbreaking AIKO panels with partial cell-level optimisation.
@@falfield Thanks for the comment. We have found that third MPPT does really help the situation and you often get shade scenarios where a consistent bank of panels will be affected. Video out this week with a good example case study. I’ll link it here when it’s launched. In that case, the system with PW3 inverter would have a yield reduction due to shading of 7.6%. With Enphase it would be 5.3%. Due to the high uplift for Enphase kit it proved to be not cost effective. In that case study we then go onto talk about how we took the bypass diode layout and half cell orientation into account. That particular customer had JA440 panels, however, we now recommend AIKO as you say.
Panel level monitoring is a nice perk but we find a lot of clients don’t care. The panels themselves break incredibly rarely. Far less often than the optimisers or microinverters. We try not to push them on people unless the data shows it’s worth it. Which it rarely is.
For this particular comment, we would have to take a detailed look at the roof and situation. But there’s only so much that one can say in a TH-cam comment without proper data…
Thank you for your technical questions and for watching the channel.
-Tok
For more detail, and for the full table comparing GivEnergy All in One and Tesla Powerwall 3, check out our article here:
blog.spiritenergy.co.uk/homeowner/all-in-one-vs-tesla-powerwall-3
I think some of the data given regarding the AIO is incorrect, for example the Giv Gateway is rated at 100A not 80A (according to the datasheet). In addition the DNO limit relating to the AIO inverter added to any Solav PV inverter doesn't seem right. I have a DNO export limit of 4kW which is addressed by limiting the export from the gateway. I never get 4kW solar so maybe I'm misunderstanding the video. Maybe for export purposes the video assumes a stand-alone AIO?
Hi Nigel, Thank you for the comment. The grid supply connection to the Giv Gateway can be rated up to 100A (protected by 100A MCB), but the load output connection is only rated up to 80A (protected by 80A MCB), and so the Gateway effectively limits your backup load supply to 80A. Ergo, it can only backup 80A.
The information is a bit obscure, and the datasheet doesn't make it clear. We were referencing the installation manual along with our own experience. Here's a link to the installation manual; see page 29, breaker D.
givenergy.co.uk/wp-content/uploads/UK-Installation-Manual-All-in-One.pdf
Regarding the DNO limitations, the video is correct. If you have a 6kW GivEnergy All in One and a 4kW solar inverter, you'd need to apply for 10kW of DNO permission. In your case, it sounds as though the DNO limited you to 4 kW, meaning you could not export your full potential-only 40% of it.
-Luke