Best Solar Panels

pvpbryan

For those who own solar panels, I was wondering which solar panels you feel are the best?

Mcfi5dhc

I have 8 * Sharp Moncrystalline NU180's - these are very good.

However, I can't really comment on how good/bad others are - I have never had any others. My system has exceeded its forecast consistently, but this could be down to good weather over the last two years, or a conservative estimate by the installers.

You also have to consider a good invertor (I've got a Sunny Boy), and cables etc.

Generally Monocrystalline PV is the best, but you pay for it (should be a solid black/blue colour by the way)
Polycrystalline PV - 2nd best, but should be a little bit cheaper (usually blue zigzaggy patterned)
Solar Hot water (in case I got the wrong gist of your post!) - unless homemade, all of them are a waste of money at the moment

If a panel is rated at 180watts (for example), on the day you buy it, in bright sunshine, it will acheive 180watts minimium. But, over time, this degrades - and this is where the cheaper panels start to lose out quickly. Mine have a low degradation factor (still will degrade though over time) and that is what you will need to consider.

Look for a good warranty as well - less than 20 years, forget about it.

Hope this helps

pvpbryan

How do you determine how quickly a panel degrades? Is that usually covered by the warranty? Sharp panels seems to be very popular, but what about the more budget panels like Yingli and Trina? If they have the same warranty, is it safe to assume similar quality and same amount of degradation over time?

Cardew

As far as I am aware there is no reliable data for the degradation of each manufacurer's panel - after all any exaustive test, by definition would take 20 years to complete. You cannot assume that if performance degrades by, say, 1% after the first year that any further degradation will be of the same magnitude.

Also will there be higher or lower degradation in, say, the blazing sun in Arizona to that in, say, North Wales.

In any case, there is little chance of any guarantee covering degradation as you would need to prove that the climatic conditions were identical, that you had cleaned the panels adequately etc etc.

yakky58

I have these panels....the link shows you some degradation statistics...

http://www.altersystems.com/catalog/sanyo-210-watt-solar-panel-hip210n-p-2002.html

Had mine nearly 4 years rated at 2050 watts max output. I have seen this reached and exceed every year so far. I clean mine 2x a year March and September. I would recommend as a decent panel.

Mcfi5dhc

Cardew wrote: »

In any case, there is little chance of any guarantee covering degradation as you would need to prove that the climatic conditions were identical, that you had cleaned the panels adequately etc etc.

This is false, and very much so

The warranty on Sharps degradation (and other suppliers) is very clear. If, in test conditions*, the panel cannot get within a percentage of the max power on a time sliding scale, it will be replaced.

So for example, if a panel in the first ten years doesn't hit greater than 90% of its spec, it has failed, and will be replaced.

You do not have to clean them religiously (though some do) - they must have been fitted by an approved installer to start off with though.

In any event, you are really going to struggle to find someone WITH solar panels and WITH a complaint about them.They are built to last, and have no moving parts, so failures are virtually unheard of. I'm sure someone will post one shortly though...

* Test conditions presumably mean take panel down, put in a light box, and record the output

yakky58

I have a wireless box fitted inline between panels and inverter that sends output figures to a hand held device it displays the following:

1) Total kwH generated (minus loss in conversion)
2) Total CO2 in kg saved, but I am dubious this is accurate
3) Current generation on the panel at the time of measuring

These roll around every three or four mins.

http://www.leiderdorpinstruments.nl/International%20web/Info%20displays/index.html

That's the link.I look in the summer months at the output figure and on bright days have noticed the panels generate over 2kwH. I also am registered with OFGEM for ROCs and
have to report monthly figures so I have a history and have not seen a massive drop so far due to degradation of the panels.

The Sanyo are good for 10 years (it maybe 15) I have not checked. So far zero issues other than I need to reset the wireless handheld as its a 4 digit display and is nearly ready to roll over to 5 figures. The company sent me instructions which I'll do in end of March ready for FIT.

frugalfran

We are currently investigating solar - one question that it raises is changing our electricity (and perhaps gas) providers (we are currently on on-line dual fuel.
Does anyone have any ideas about this? Thanks in advance.....

Cardew

Mcfi5dhc wrote: »

This is false, and very much so

The warranty on Sharps degradation (and other suppliers) is very clear. If, in test conditions*, the panel cannot get within a percentage of the max power on a time sliding scale, it will be replaced.

So for example, if a panel in the first ten years doesn't hit greater than 90% of its spec, it has failed, and will be replaced.

You do not have to clean them religiously (though some do) - they must have been fitted by an approved installer to start off with though.

In any event, you are really going to struggle to find someone WITH solar panels and WITH a complaint about them.They are built to last, and have no moving parts, so failures are virtually unheard of. I'm sure someone will post one shortly though...

* Test conditions presumably mean take panel down, put in a light box, and record the output

I agree that the panels themselves are inherently reliable - otherwise they wouldn't have such a long warranty.

My point was that if you have an array and you suspect one(or more) of the panels is faulty because you are getting low output, what solution do you have(and that was the question posed)

Get the approved installer to come and remove all panels and carry out tests?

Who pays!!

Mcfi5dhc

Cardew wrote: »

I agree that the panels themselves are inherently reliable - otherwise they wouldn't have such a long warranty.

My point was that if you have an array and you suspect one(or more) of the panels is faulty because you are getting low output, what solution do you have(and that was the question posed)

Get the approved installer to come and remove all panels and carry out tests?

Who pays!!

Its fairly irrelevant, because its unlikely to ever happen, but...

SOGA states your contract it with the installer.

Installer will have fitted a meter anyway, so you can test it yourself (in one hour of bright daylight, you should hit 90%+ of your kwp rating)

Phone installers up, they'll be in utter amazement to hear of a fault, but as they are nice people, I'm sure they'll come along and plug their meter in for free. They'll phone up Sharp/Sanyo/whoever, who will also be in utter amazement that a panel might not be performing properly. Homeowner should not have to pay a penny. Claim should be sorted from here.

* If installer has gone bust/closed/other reason you can't contact installer, skip straight to the helpful helplines that Sharp/Sanyo etc have (prepare for their amazement when you say you think your panel is underperforming)

I'll leave the following space to complete for all those who have had issues with panels (PM me, and I'll edit it each time):

1)
2)
3)

Thanks

yakky58

FrugalFran

I am with Southern & Scottish. They are very good with dealing with microgeneration. they gave me an export meter for free and set up the bill to include generation. I have dual fuel with them. I am sure there are cheaper deals but the generation side they have been brilliant.

PM me and I'll send the email contact so you can get details of the offer.