Are some PV panels better than others?

[Gozoman]

I'm currently unemployed and thinking of having Solar PV installed on my roof so obviously I want the best system I can get for the least outlay. I have already received one quote of £3500 and I would like to ask members opinions on this. The System size is quoted as 1880 Watts and the panel type as Linuo P235W and number of panels is 8. Annual generation is quoted as £273.68 and export payment as £24.10 and avoided tariff as £116.63. They list payback period as 8.48 years but it says that this is based on reclaiming VAT back for commercial jobs which I find odd as it's my home it will be installed on and not a commercial property. Have they just did this to make the system look better? Total annual income is listed as £414.41. The roof in question has a gross/active PV surface area of 13.11 / 13.43 square meters with a yield reduction due to shading of 6%. System efficiency is listed as 11.8%. My roof faces due South.

Does this sound like a good deal? My main concern is not the £3500 outlay but the system size of 1880 Watts as I would prefer something higher. So my main question is this. If a different panel was used on the same given area of roof could I expect to get a higher output? What would be the best output I could expect from today's technology and at what extra cost. Many thanks in advance for any information and advice.

 

[Vegelen]

Consider installing a solar system when you are back in full employment.
Save your cash reserves until returning to work, to protect your financial circumstances.
Solar systems are excellent, incremental investments that will help reduce your electricity bills and supplement your income long term. They arent get rich quick schemes.
Your roof has a surface area of 13.11 / 13.43 square meters.
As your roof is small it will be important to use solar panels with as high efficiency as possible, to maximise generation on a small southerly facing area.
The most efficient solar panels are expensive (Panasonic HITS, Sunpower etc), so you'll have to decide how much money you are prepared to spend versus, the net benefit.
Use the following websites to help you discover what panels could be installed on your chosen installation location:

CompareMySolar - Compare solar panel prices and installers in the UK
Best Photovoltaic Solar Panels | Unbiased, Data-Driven Comparisons.
Compare Solar Panels

High efficiency solar panels allow you to generate more energy in a limited space.
You need to look at a variety of solar panels and work out what solar panel will best fit the area available, how much will it generate, for what cost.
The more efficient a panel, the more it will generate for a limited area.
But the more efficient a solar panel is, the more expensive they are to buy.
All 250W solar panels dont generate exactly same amount of power, they have different specified tolerances i.e +5% or +- 3%.
The less efficient a solar panel is, the larger its size will be to generate a similar amount of power.
As your roof suffers from shading it is important to install a solar system that works well with shading issues.

There are many options available designed to work with shading:
(1) Solar Inverters /DC-DC Solar Panel Optimisers (Tigo,Aurora Power One,SolarEdge etc).
(2) Microinverters (Enphase, Enecsys, SMA (Due Q3 2013)).
(3) Solar Edge with Solar Edge Panel Optimisers.
(4) Solar Inverter with Software Algorithm (SMA Inverter with Optitrac Global Peak).

Your roof is small so your options may be limited to (1) & (2).

Solar systems installed on smaller roofs tend to be more difficult to design because of various design constraints i.e small roof area, limited range of high efficiency solar panels & low power inverters etc.
Also solar system efficiency comes into play.
The smaller a solar system is the less efficient its operating efficiency is likely to be.
There are many people on this forum that will be able to help you further, with additional analysis of your system design, following this posting.

 

[Gozoman]

Thanks for that Vegelen. I'll check out those sites. I'm not after a get rich scheme by any means. I have the cash lying doing nothing anyway so at least with a solar PV system it would be doing some good and hopefully pay for itself in about 7 years at which point I will have reached retirement age. After that any cheques I get in will be a top up for my pension.

 

[moggy1968]

there is no value in going for 235's. 250s are probably the same size. It's only worth going for something like panasonic if it increases the number of panels you can fit (because of their small size).

what are the actual dimensions of your roof?

I would say if you need to use up some savings because it has a negative effect on your benefits this is worth doing, but not with that firm, they aren't being upfront and honest. get a couple more quotes in.

 

[Gozoman]

Yeah that's what I'm doing at the moment Moggy. Hopefully I will have at least another survey done next week.

 

[Vegelen]

If you find the ideal solar panel for your roof is from a Chinese manufacturer, make sure your MCS installer buys advanced stock before the EU introduces anti dumping taxes on imported Chinese solar panels into the EU.
The European parliament intends to take the UK government to court for charging 5% VAT on solar hardware for domestic installs.
They want to increase UK VAT to 20% on solar hardware.
These 2 factors will significantly increase solar hardware costs in the short term.

 

[Gozoman]

I can assure you that if any installer suggest fitting anything Chinese to my roof they will be told where to stick it. I wouldn't have anything Chinese in the house!

 

[Vegelen]

I understand the sentiment, I get fed up with buying and fixing many cheap Chinese items, but in fairness to the Chinese some Tier 1 solar panels / hardware are made to exceptionally high standards on German production lines with Centrotherm equipment.
I'd avoid buying Chinese inverters, as German solar inverter hardware is expensive but more reliable, although the Chinese are catching up fast.
SMA are exceptional at replacing failed hardware under warranty should anything go wrong.

 

[Gozoman]

I don't much like the Chinese and their flooding of the world with fakes and substandard products. But I hate them more now as the company I worked for moved the majority of their operation to China and I ended up out of a job!

 

[SRE]

Ahem! Linuo - Chinese manufacturer ....... I think you'll find a good 85 - 90% of panels installed in the UK are made in China, along with an increasing number of inverters. Some installers would go as far as to say they would have some Chinese manufacturers over Sharp panels made in the UK. If you're wanting bargain prices then you may well end up with Chinese panels ON your house.

 

[Gozoman]

I can assure you I won't mate. That's why they are fast becoming the most powerful nation on earth because we are financing it. I don't intend to help them in that regard. I don't want any cheap Chinese rubbish on my roof and I'm prepared to pay extra to ensure that doesn't happen. My main concern is quality rather than cost.

 

[Vegelen]

If you're wanting bargain prices then you may well end up with Chinese panels ON your house.

* This is a time limited offer.
The EU are recording Chinese imports into the Eurozone, with a view to introducing retrospective anti dumping levys.
Want cheap Chinese panels? - Buy soon to avoid imminent price hikes.
Or follow Gozoman's lead and give them the bum's rush.

 

[finchy]

Where are you located Gozoman. I would get a quote from some of the regular contributors on here. Only use Real and Mcs companies check their credentials on the website. http://www.microgenerationcertification.org/

It's not a decision to rush, once you have found an installer you then can get prices for alternative panels inverters and output predictions.

 

[Gozoman]

Hi Finchy. I'm based in N. Ireland so probably not as many installers here as on the mainland.

 

[SRE]

I can assure you I won't mate. That's why they are fast becoming the most powerful nation on earth because we are financing it. I don't intend to help them in that regard. I don't want any cheap Chinese rubbish on my roof and I'm prepared to pay extra to ensure that doesn't happen. My main concern is quality rather than cost.

Good to hear, wish our customers were the same but the vast majority are very price sensitive. We're in a low wage area and those with cash have probably just got as much as those perceived to earn low amounts in other parts of the country. So in short even the cash rich in our area haven't got much cash!

 

[jason121]

How many of you on this forum have Apple Iphone or IPADs were do you think they are made.

 

[Gozoman]

What I really need to know here is this. I have been quoted for a system which has 8 Linuo P235W panels having a total system size of 1880 Watts. The panels are Chinese which I certainly don't want and the system efficiency is stated as being 11.8% which okay I'm no expert but that doesn't sound great given there are panels on the market with over 20% efficiency. Given the footprint of these 8 Linuo P235W panels as that appears to be my limit area wise are there other panels I could request which would give me a better efficiency and a higher overall output? Also can anyone comment on the inverter which they propose fitting in this system which is a Samil Power Co. SolarRiver 1600TL 1.5kw? I suppose this is more Chinese made stuff? I may seem to be coming down hard on the Chinese here but I really don't want to trust my property or my life to an electrical component made in China where quality and health and safety are nil!

 

[Gozoman]

Point taken Jason as I have a new iPhone 5. However I didn't have a choice in the matter as it was a present from a friend and I don't think there is a possibility that it will malfunction to the degree where it might burn my house down!

 

[Vegelen]

:leaving:

 

[Vegelen]

I don't think there is a possibility that it will malfunction to the degree where it might burn my house down!

That's what Beko fridge freezer owners said.....:ihih:

​

 

[Gozoman]

Sorry you feel that way Vegelen. Personally I thought that was the idea of the forum, to provide an opportunity for people with the necessary knowledge and experience in a particular subject to help others by passing that knowledge and experience on. Personally if someone with your attitude called at my house to quote for a job I'd tell you where you could go!

 

[Vegelen]

Earlier in the posting I provided you with a number of website's showing you solar panels, their efficiency, size etc to help you find the best solar panels for your roof.

You indicated that you didnt like Chinese products and wouldnt buy them.

You mentioned that you'd been offered Chinese manufactured Samil Inverters and Chinese manufactured Linuo solar panels, which you asked forum members for opinions on.

A 5 second internet search would tell you about the provenance of Samil inverters and Linuo panels.

 

[SolarCity]

I don't have much to add to this discussion (as I'm on a sporadic hotel Wifi connection for a start), but I will say that "Cheap Chinese crap" isn't a very accurate description of most imported panels.

Linuo are great panels. If you decide against these and choose to install British made instead, then there is a very high probability that you will pay more for a lesser quality item.

But as you suggest earlier in this thread, you may buy British out of loyalty anyway.

 

[Gozoman]

To be honest Solarcity I didn't know that panels were manufactured in Britain, but now that I do I would probably agree with you that the quality might not be up to some of the more established makers. And it's not a case of buying British out of any form of loyality. I would probably be more inclined to buy German as I have always found the quality of German products to be better. But that the whole point of my original post. I could run a search on the web and find these great write-ups about German panels or French panels or Swiss panels or whatever but where would that get me? I thought that people who were installing them for a living and had been doing so for years would be able to give an honest opinion of what to go for. I have no doubt there are quality products coming out of China but practically every fake product in this country was made in China. If you were fitting wall sockets in a house would you go for a trusted make like MK or would you be happy fitting MK fakes made in China which have been shown to catch fire under load? As an electrician you would probably be able to spot the difference but they would look the same to me. I can't see me going with the Chinese manufactured Samil Inverter and Chinese manufactured Linuo solar panels because I just wouldn't trust them. And when the panels are only rated at 11.8% efficiency they wouldn't be worth it anyway.

​

 

[Vegelen]

SMA are very high quality German inverters with a long operational reliability record - expensive but good.
The Chinese Solar panel manufacturers undercut the German solar panel manufacturers and many German companies went bankrupt, due to the Chinese dumping solar panels in Europe at very low prices. The manufacturing equipment from many of these factories was shipped overseas to China.
Now some German panels are made in China, to the same standards they were made in Germany, on German production lines.
The Chinese solar industry is currently over producing solar panels and prices have reduced as supply is far exceeding demand.
China is trying to stimulate its internal solar market to try to mop up some of this excess oversupply.
It is a good time to buy solar hardware due to current low prices.
If you feel very strongly about buying Chinese hardware, there are a few European factories that still manufacture panels.

 

[Gary K]

You need to make a decision as to how much cash you are prepared to spend. If you want a decent system for as little as possible then it is very likely you will end up with chinese panels but as already stated, they are in the whole not a bad product. If on the other hand you want to cram as much output as possible on your smallish roof,then you will have to pay out for premium panels like Panasonic(sanyo) or Sunpower which have efficiency getting on for 20% but as always for quality gear, you may end up paying getting on for double(at a guess) what the cheaper system costs.

 

[Gozoman]

I'm beginning to see that this is going to be a minefield if German branded panels are coming out of China! I often think what a better world it would be if China sank!

 

[Gozoman]

Thanks for that Gary. I have read that Sunpower are very good but as you say very expensive to match. As you say my problem is a small roof so I really need to get as much output as possible. Not sure I could stretch to double my present quote to achieve that though!

 

[Vegelen]

Focus on finding the right solar panel for your limited roof space, with a good efficiency, at an acceptable price and quality.
The links I specified earlier, will help you do this.
I'd personally install Monocrystaline solar panels, in preference to Poly's but thats a personal choice as many good Polycrystaline panels exist.
Canadian Solar, Linuo, Panasonic, REW Premium Plus, Suntech, Sunpower, Znshine are excellent panel manufacturers.
Be careful which panels you choose from a chosen manufacturer as panel efficiency / quality can and does vary from brand to brand.

 

[Gozoman]

Thanks Vegelen.

 

[SRE]

Of course if you work with a local installer, who can show you several satisfied customers and you don't force the price down they will be happy to show you the way to go. It's taken a long time and quite a bit of trial and error to get the expertise found on the forum. There's little more frustrating than someone picking your brains and then screwing you on price. If you want a quality installation service you will need to pay for it, but installers on here provide that service at a fair price.

 

[Gozoman]

I don't think there is anyone local. If there is I haven't found them. Closest I have found I think was Belfast.

 

[SRE]

I se what you mean - only 2 installers in NI Microgeneration Certification Scheme - Installer Search. If you ask nicely maybe one of the guys on the forum might be prepared to drive over and do the job for you - obviously you'd need to pay for the travel etc but then again you'd know you were getting good info and a decent installation. It's a long term investment so you should get the job done properly

 

[Gozoman]

I'm waiting for a PowerNI rep to call me next week to arrange an appointment. Given that I used to work gor them and they are the power suppliers here I'd like to see what they can offer. Trying to get them to contact me is like pulling teeth. You would tghink they would be glad of the work but after two emails went unanswered I had to ring them on Friday. Hopewfully I'll know more by the end of next week.

 

[SRE]

My advice would be to talk to a smaller company and definitely not a rep. Yesterday I went to a house where they had had 4 reps in the last 2 days. Some wanted to install on a N facing roof, some wanted to put 1kwp more than the roof would hold, none saw a chimney on the middle of the roof or that the roof needed re-inforcing. A rep will move from job to job, my customers can knock on the door if anything goes wrong. I don't want them to do that so we make sure they get the job they deserve not the one that helps us hit our bonus. You are in a difficult position but it may pay to work with someone who has had their MCS longer than June 2012 when the market was on it's knees.

 

[moggy1968]

I would say SMA are the inverter to go for. they're German, superb quality and have a great bluetooth interface as standard (on HF and TL, don't take any other SMA inverters though as they will be older and less efficient).

The other option might be microinverters such as enphase which will maximise your yield and could produce upto 20% more for an extra cost of about £600, more cost effective then going for something like panasonic panels.

IT may help if people name you some panels which aren't Chinese so you can research them, so here's a few to kick off with. Bosch (German) Samsung (Korean), Canadian Solar (strangely enough. Canadian!). Don't be fooled by Chinese panels with names that don't sound chinese. Some of the bigger instalers import container loads of chinese panels, some of which are rubbish, and put their own european sounding name on them. There are good chinese panels, Yingli and Suntec for example but I understand your reasoning.

I would like to say it is refreshing to see someone interested in more than just price, the pound shop mentality of some in this business properly does my head in!

 

[Gozoman]

No problem that way with PowerNI as they are the company in N. Ireland that own and run all the power stations and who I pay my bill to every quarter.

 

[Gozoman]

Thanks for that Moggy. I'm taking a note of these recomended panels and the inverter. Are the HF and TL you mention models of SMA inverters?

I'll have a look and see if I can find some information on those microinverters you mention.

 

[moggy1968]

they are yes

 

[Gozoman]

Moggy I was looking at that M125 Enphase Microinverter. Let me see if I understand this right. This uses a separate Microinverter for each installed solar panel. Are these a replacement for the usual inverter fitted in the loft or do they work along with it? Are there any problems with them being exposed to the elements?