PV Panel War: Sanyo v. Hengji. The ultimate side-by-side long-term, real-world test.

[Vegelen]

Re: PV Panel War: Sanyo v. Hengji. The ultimate side-by-side long-term, real-world t

Thor v Uxello Solar:

Ask questions and enter the debate....

Help me explain why the latest Suntech monocrystallines should be performing so well relative to Sanyo 250 HITS on 2 similar systems 10km apart.

The Suntech solar array with transformerless inverter was earthed on the 28th March 2012.

Since that date the 2 systems relative performance has narrowed.

 

[morpheus75]

Great experiment would love to hear how its all going over the course of the year(s) to come.


Sent from my iPhone using Tapatalk

 

[SolarCity]

Re: PV Panel War: Sanyo v. Hengji. The ultimate side-by-side long-term, real-world t

How can you be sure that they are in equal conditions?

 

[Vegelen]

Re: PV Panel War: Sanyo v. Hengji. The ultimate side-by-side long-term, real-world t

How can you be sure that they are in equal conditions?

The only way equal conditions can be found is by installing side by side.

Do you know a millionaire locally that will fund such an experiment?

I'd be happy to see the results.

I know what we'd find, that the Sanyo 250 HIT's generate marginally more than the

latest Suntech's. The Suntech STP250S - 20/Wd monocrystaline panels have a

module efficiency of 15.2% versus 18% on the Sanyo HIT-H250-E1.

The Sanyo HIT 240's are 19% and the latest Sunpowers at approximately 20-21%.

All are very much more expensive.

Economically they wouldn't be worth investing in over 25 years, unless maximising

solar power generation for a fixed size of roof, where panel size affected the amount

of panels that could be installed in a limited space.

Anyone with a commercial interest in installing Sanyo Hits would be likely to

challenge these results, as they have economic interests to protect.

Unfortunately I dont.

I care to find the best quality panel, outputting the most energy over 25 years, In

typical conditions that prevail in North West England.

If I lived in Greece with greater average sunshine another panel may be my panel of choice.

Some PV panels perform better in low light than others etc.

Some perform better in high light conditions and greater temperatures etc.

Choosing the right solar panel for your environment, depends on where you live, the

typical weather conditions that surround you, your size of roof and a few additional

factors, IMHO.

 

[SolarCity]

Re: PV Panel War: Sanyo v. Hengji. The ultimate side-by-side long-term, real-world t

The only way equal conditions can be found is by installing side by side.

Do you know a millionaire locally that will fund such an experiment?

I'd be happy to see the results.

As would I.

All I am saying is that to compare these two systems is not very good science, particularly when you understand just how much impact orientation, pitch and shading can have on a system.

To take these two systems and then to go and make a conclusion based on the results is not going to very accurate.

 

[Vegelen]

Re: PV Panel War: Sanyo v. Hengji. The ultimate side-by-side long-term, real-world t

Unless you have tried to do your homework and understand the impact of such factors....

The difference in roof declination of 30 Degrees compared with 45 degrees amounts to a potential difference of 4% in system output of comparable systems, if the roofs are within +/- 10 Degrees of Due South.

If the roofs are orientated within + or - 40 Degrees of Due South, the difference in system output can be as much as 7-8%.

I know these 2 solar systems have comparable shading, that they are located close to one another at similar altitudes / orientations and that they have similar weather. The roofs have a different inclination, which affects output between the two systems by 4%.

I have tried to compare the outputs of 2 comparable systems scientifically, but others may agree to differ.
I have found the latest Suntech STP250S - 20/Wd to compare favourably to the
Sanyo's 250 HIT's. I am seeing a 4-5 % difference in generation between the 2 in current climatic conditions in March 2012 in North West England.

If the Sanyo Hits lost 4-8% maximum generation output based on roof declination / orientation in a worse case scenario, how much more energy are they likely to generate than the Suntech STP250S - 20/Wd solar panels for a 40-50% cost premium? 8-13%?

 

[SolarCity]

Re: PV Panel War: Sanyo v. Hengji. The ultimate side-by-side long-term, real-world t

I know these 2 solar systems have comparable shading, that they are located closed to one another at similar altitudes / orientations and that they have similar weather.

I'm not trying to be difficult, I'm just trying to make sure that the analysis is accurate.

Have you seen the sites and compared them both or are you just going off the PVOutput details?

 

[Vegelen]

Re: PV Panel War: Sanyo v. Hengji. The ultimate side-by-side long-term, real-world t

To compare these two systems is not very good science, particularly when you understand just how much impact orientation, pitch and shading can have on a system.

If there is no shading and we know the relative pitch is 30 Degrees versus 45 Degrees and the orientation of both houses is within 10 degrees of due south, both houses use similar inverters on comparable sized systems, we know the panels on both roofs, the houses are within 10km of one another, the panels are both orientated landscape on the roofs, please explain why such a real time experiment cant glean us any useful information?
It seems to me that in this world there are too many people, protecting their interests or failing to employ common sense.
It is clear that Sanyo HITs are excellent solar panels, but they are far too over priced for what they are and many competitively priced solar panels exist to replace them with.
To say this publically comparing "apples and pears" presenting real time analysis of 2 similar systems in the real world, threatens people with a vested interest in stocking and installing them.
It is not difficult to see the relative performances of Sanyo v Suntech solar pv panels, but until they are put side by side, all and sundry will argue about one panel versus another until definitive proof exists one way or another.

IMHO Sanyo's HIT panel systems are 20-30% more expensive to buy and generate 5-12% more KWh than comparable Suntech PV systems, in comparable locations, with similar roof inclinations and climate.

 

[Gavin A]

Re: PV Panel War: Sanyo v. Hengji. The ultimate side-by-side long-term, real-world t

The Sanyo Hit panels are currently outperforming the monocrystalline Suntechs by 4-5%. They cost a 40-55% premium.

well if it's 4-5% improvement, then this is in line with what we've been estimating for our performance estimates.

The cost premiums you give though are pretty misleading, as these purely compare the panel prices, rather than the whole installed system prices. The difference in the system prices is around 20-30%.

The major benefit of installing Sanyo systems though comes on roofs with limited roof space where the Sanyo systems can usually fit between 20-30% more actual generation capacity in the same roof area. At this point, this plus the 5% improvement in performance starts to make the payback times / ROI for a 4kW Sanyo vs eg a 3.3kW mono system be relatively equivalent.

Before the big price cuts recently the Sanyo systems actually came out better in those calculations than the cheaper systems most of the time. The situation now is a little different as the standard PV prices have dropped so much, but it's still worthwhile enough for more than half of our installs last month to have been Sanyos when we quote and give performance estimates for both options. Not sure what it will be like at 21p with no potential for 43.3p FIT mind, time will tell, but my feeling is that the Sanyos will still be popular.

 

[SolarCity]

Re: PV Panel War: Sanyo v. Hengji. The ultimate side-by-side long-term, real-world t

If there is no shading and we know the relative pitch is 30 Degrees versus 45 Degrees and the orientation of both houses is within 10 degrees of due south.

How do you know there is no shading? I know it seems like a strange question but I visit plenty of sites where an installer and the customer has declared that there is no shading. They have also measured the orientation of the roofs poorly. I have seen plenty of SE or SW facing roofs with chimneys and neighbour's roofs shading parts of the array where other companies have run SAP figures as south facing/unshaded.

please explain why such a real time experiment cant glean us any useful information?

I'm not saying it is not useful. I am saying that it is providing information. It is how you interpret this information that is important. To look at two different arrays on a website and draw conclusions on that is just bad science - there are too many factors that you cannot know.

It seems to me that in this world there are too many people, protecting their interests or failing to employ common sense.
It is clear that Sanyo HITs are excellent solar panels, but they are far too over priced for what they are and many competitively priced solar panels exist to replace them with.
To say this publically comparing "apples and pears" presenting real time analysis of 2 similar systems in the real world, threatens people with a vested interest in stocking and installing them.

You seem to be implying that I stock Sanyo panels and that I'm therefore trying to give them a public 'boost'. You are incorrect. Indeed, if you do a search, you will often read comments from myself praising Suntech panels as a better value for money option than Sanyo.

 

[Gary K]

Re: PV Panel War: Sanyo v. Hengji. The ultimate side-by-side long-term, real-world t

I know its only nearly 3 months from fitting but do we have any conclusions/updates yet?

 

[mbuckhurst]

Re: PV Panel War: Sanyo v. Hengji. The ultimate side-by-side long-term, real-world t

These experiments, although possibly flawed (though I would say in relatively fixed manner which could be eliminated to a reasonable extent), are better than anything else we have to go on. When installing my system I found most installers didn't understand the basics of the Physics, so had no way to explain why things like shading matter (I have a wife with a Ph.D. in semiconductor Physics so have an insider ), so any real world comparisons, no matter whether they're 100% comparable is going to be useful. And thanks for doing these.

My system is Sanyo based, not for any other reason than I wanted to get the most out, didn't care so much about the cost, and at the time the difference in price wasn't 40-50%. Now it's been installed for 6 months, I've noticed several interesting facts, I have shading issues on some of the install, and used micro-inverters to ensure the system wasn't as badly impacted. I also need the highest output for the size of panel, since if larger panels were used more of any panel and possibly more panels would have been affected by the shading, if I could get the same number on the roof.

1) No panel produces the same output, even where I have panels in a rectangle in full sunlight, each will disagree with the neighbour above, below or sideways by as much as 10% and almost always there's a variance of 2% between neighbours. So any test with a large array next to another large array is never going to be perfect, but better than nothing.

2) The angle of the panels affects the output more when the sun if full on, I've got 2 pairs of 4 panels facing the same direction at the same height but slightly different angles, at this time of year I get between 1 and 5% difference in output between them, peaking around lunchtime and early morning/late evening there's no difference, however, over the year, I expect the benefit to switch between the two as the sun gets higher still.

3) Temperature is a huge factor, when it's chilly and full sun, my panels exceed spec. by around 11%, now the sunshine has arrived nowhere near this level (although it's potentially more hazy with the overall increase in air temperature). Also, they still generate with snow - though not huge amounts of electricity, unlike my thermal panels which ran continuously during a sunny winters day, covered with around 10cm of snow.

4) My chimney stack that put 90% of installers off, because it couldn't be done, rather than can we minimise the impact, at this time of year, is only shading one panel to any level, the shadow itself has shortened significantly to the point it only glances 2 panels and shades a 3rd. But of course at this time of year I'm doing 85% of the annual generation, so the actual impact is less significant than anyone predicted (yesterday I generated the same in one day as the whole of December). I've never once seen an installer consider anything beyond the that tree or chimney shades the panel, don't install. My neighbours were told by an installer that we were stupid as they wouldn't work, whilst I'm watching the shaded 5 panels generate nearly 1kWh at 10am, and a lot more at lunchtime.

mike

 

[series530]

Re: PV Panel War: Sanyo v. Hengji. The ultimate side-by-side long-term, real-world t

Very similar for me .... Sanyo and Enecsys with some shading (but less of an issue with higher sun). We're down to about 80% efficiency with the hot weather. A few days ago we were touching 100 and even occasionally beyond.

Today has been the first day ever where we experienced a near perfect bell curve. Up until then the chimney had caused some shading. It still does but only after 5pm.

Even so, best performance ever in the past couple of days. It's never going to be as good as a gentle inclined roof with no shade but it looks a whole lot better than it did a few days ago.

 

[mbuckhurst]

Re: PV Panel War: Sanyo v. Hengji. The ultimate side-by-side long-term, real-world t

Very similar for me .... Sanyo and Enecsys with some shading (but less of an issue with higher sun). We're down to about 80% efficiency with the hot weather. A few days ago we were touching 100 and even occasionally beyond.

Today has been the first day ever where we experienced a near perfect bell curve. Up until then the chimney had caused some shading. It still does but only after 5pm.

Even so, best performance ever in the past couple of days. It's never going to be as good as a gentle inclined roof with no shade but it looks a whole lot better than it did a few days ago.

1 month ago I peaked at 264W from a single 240W panel, and my best ever day under cool conditions, 15th April, we peaked at 262/263W across 9 panels and the remainder showing 255W or more, with the exception of my panel that can't communicate until evening.

One thing I have noticed, even with shading, for the first 6 months, which is roughly the a mirror of what you'd expect for the second 6 months, both my main panels with shading issues, have still managed more than 60% of the total managed by the panels with no shading whatsoever.

This is interesting because there was the choice to drop those panels from the system altogether saving something like £1000, but in reality only 40% of that number because we're not gaining the electricity either, so on balance I've lost £400 of that figure, all of the other costs would have remained static, but both of these panels is currently on target to achieve £50 per year or more, meaning that they pay for themselves in around 8 years, which is actually around the predicted pay back of the whole system.

The conclusion I can come to is that it's worth fitting panels in shaded positions providing

1) By not fitting them you don't save more than the cost of the panel/micro-inverter.

2) The shading should not cause more than 50% of the day to be lost. In reality only in the summer does this matter, it can be in full shade for november, december and january and it won't have much impact.

3) If you use a sting inverter, you have to be sure you don't compromise the whole string when a shaded panel is in the string.

Point 3 is interesting because the unwritten rule from the installers perspective seems to be one panel out, all out, unless the string is large enough to cope - in my case it wouldn't be. Depending on whether this rule is true or not, and I don't have any evidence either way, except to know, a panel with only a small amount of shade (maybe 10-20%) fails to operate. But if this is the case it proves the sense in fitting micro-inverters over standard string inverters in many cases where shade is unavoidable.

mike

 

[Gavin A]

Re: PV Panel War: Sanyo v. Hengji. The ultimate side-by-side long-term, real-world t

I've never once seen an installer consider anything beyond the that tree or chimney shades the panel, don't install.

fwiw, we produce full 3d models of every building we install on and can estimate the shading impact very precisely on average for each hour of daylight for each month of the year, and use this to design the system to absolutely minimise the shading impact.

We actually don't use micro inveters though, as we've never found a situation where the figures stacked up to mean that their benefits outweighed the reduced efficiency of the micro inverters vs an SMA 4000TL, which with Optitrac global peak enabled will already greatly reduce any shading impact on a properly designed system to get the best out of the panels in built bypass diodes to bypass any shaded strings of cells.

Took us a fair amount of time, effort and scratching of heads to get to that point though.