Solar Panel Guide Discussion

ed110220

Lei_Chat wrote: »

Do some inverters and/or panels have better thresholds or is that just sales banter?

If I'm to believe the sales pitch the latest hardware can generate energy for longer each day in more cloudy weather than the older brands.

Like Mart I'm skeptical of claims that one panel performs better than others. Photon.Info have been field testing panels at Aachen in northern Germany so in a climate broadly similar to that of the UK. The latest results (Jan-Nov 2014) are available here: http://www.photon.info/upload/YM_Results_November_2014_engl_5205.pdf. I think the kWh per kW of panel are surprisingly close. The best achieved 1160.7 kWh/kW and the worst was 902.3 with most clustered around 1100.

You also have to remember that the wattage of a panel is not necessarily exact. Different manufacturers have different tolerances for their models. Taking two at random:-

Panasonic give a tolerance of +10/-5% for their 245W panel, so the true wattage under standard conditions could be between 232.75 and 269.5W

Hyundai give +3/-0% for their 250W, so the true wattage could be between 250 and 257.5W

So much (or even most) of the difference in Photon's results could be due to chance ie whether they happened to get a panel at the top, middle or bottom of the tolerance range.

Ed

Misslayed

My 14 Enphase panels went live on 18th December last year. They each have their own micro inverter. I can't do much tecky talk, but I don't mind sharing our electrickery production and income if it helps anyone. We chose this system from 4 quotes because the very knowledgable young man spoke about the future of solar panels. He is always looking at the next step, unlike others who assured us they had 'used these panels without any problems for five years'. That seemed to us a bit like promoting the same TV or camera for five years. We are lucky enough to live on the south coast, have a south facing roof and no shading. Happy to help!

zeupater

Misslayed wrote: »

My 14 Enphase panels went live on 18th December last year. They each have their own micro inverter. I can't do much tecky talk, but I don't mind sharing our electrickery production and income if it helps anyone. We chose this system from 4 quotes because the very knowledgable young man spoke about the future of solar panels. He is always looking at the next step, unlike others who assured us they had 'used these panels without any problems for five years'. That seemed to us a bit like promoting the same TV or camera for five years. We are lucky enough to live on the south coast, have a south facing roof and no shading. Happy to help!

Hi Misslayed ... Welcome to the forum ...

Apologies for being particularly blunt, but considering that micro-inverters are suited to combat shading issue and you state that you have no shading, the 'very knowledgable young man'[sic] has probably simply used his knowledge of sales techniques to upsell the product and increase his margins & commission, nothing to do with the 'future of solar panels' at all ....

Enphase are the manufacturers of the micro-inverters & (to my knowledge) have no interest in panel manufacture or particular technology as long as they suit their product, so the panels you have could be anything from the cheapest polycrystalline makes available, to high efficiency expensive mono-crystalline or hybrid units ....

On this forum and elsewhere we're seeing an increasing number of references to sales representatives encouraging customers to select a more expensive product solutions which they didn't really need .... as you have already had your system installed, I do hope that the system wasn't a silly price and that it does perform well for you. Considering that you 'can't do much tecky talk' [sic], it's just a shame that you didn't come to the forum to glean some of the basics from those with pv or just ask for impartial views before committing to the install ...

HTH
Z

Misslayed

I did come to the forum, and the high level of tecky talk was no use to me at all. Too much information. However I'm very happy with the return on my investment, which is looking like at least 8% based on current figures, not counting the saving on electricity. My last quarter happened to coincide with my first quarter with PV panels, and my bill was 20% lower than last year. I've generated half as much in the last three weeks as I generated in the first quarter, which bodes well for returns in the spring/summer/autumn months. This is the kind of basic information I was looking for when I searched the forum. Hence my post. I used a local, trusted, long standing family firm as installer, whose quote was marginally higher than the other three I received.

Martyn1981

Misslayed wrote: »

I did come to the forum, and the high level of tecky talk was no use to me at all. Too much information. However I'm very happy with the return on my investment, which is looking like at least 8% based on current figures, not counting the saving on electricity. My last quarter happened to coincide with my first quarter with PV panels, and my bill was 20% lower than last year. I've generated half as much in the last three weeks as I generated in the first quarter, which bodes well for returns in the spring/summer/autumn months. This is the kind of basic information I was looking for when I searched the forum. Hence my post. I used a local, trusted, long standing family firm as installer, whose quote was marginally higher than the other three I received.

Hiya Misslayed and welcome. Whilst you clearly didn't mean to cause any offence, I can't help but be a little offended by your posts.

Firstly, how can there ever be too much information? I think the PV FAQs are set at a level that most people will understand, and encourage readers to post and ask questions. If the information is too detailed or irrelevant then the reader can skim or ignore irrelevant sections.

I'm not a techy person, and am constantly aware that my posts are both long and boring, but that's because I try to be clear, and explain each step / option / suggestion as I go along. I personally think that that is the same as most of the PV'ers on here that post information purely to help and advise. Again, overly complicated/detailed posts can be skimmed or skipped. However, threads generally start of simple and get more complicated as detailed information is requested and more complex solutions are sometimes needed.

I also believe that all of us sharing info are more than happy to explain anything that doesn't make sense, and 'hold prospective PV'ers hands' when asked. Evidenced by dozens, possibly hundreds of threads over the last 4+ years.

Most threads also give the basic information (that you say you searched for) by explaining generation estimates, income streams, breakdowns, and returns on investment.

Lastly, given your system description .....

Misslayed wrote: »

We are lucky enough to live on the south coast, have a south facing roof and no shading.

..... I'm a little shocked at your 8% return figure.

Since generation should be around 1,000kWh per kWp of installed PV, and assuming you have a 4kWp system, then income (before leccy savings) should be approx 4,000 x 17p = £680.

If you followed the basic advice on this board, then you should have paid £6k or less in late 2014. So £680/£6k = 11.33% ROI

Had you avoided micro-inverters (or power optimisers), devices that do an excellent job (shade mitigation), but do unfortunately mean extra kit placed in hard to reach locations, then returns may have been £680/£5.5k = 12.36%.

An 8% ROI would suggest a price north of £8k, something that all of us on here would have been quick to advise against (given the opportunity) and our 'good intentions' to prevent prospective PV'ers getting ripped off.

Mart.

tunnel

Misslayed wrote: »

I did come to the forum, and the high level of tecky talk was no use to me at all..

After looking at your previous posts you certainly didn't ask for any advice like the many dozens of people who have been before you on the forums


The good folk who post on here do try their hardest to explain in simple terms the merits and pitfalls of all aspects of solar, we're not here to help you part with your hard earned cash, none of us are installers either, we are just fellow PV'ers who take an interest in the industry.


I'm glad you are happy with your install....BUT...are you as happy now knowing you were sold kit that wasn't needed and probably paid well over the odds for?

ed110220

Misslayed wrote: »

My last quarter happened to coincide with my first quarter with PV panels, and my bill was 20% lower than last year... This is the kind of basic information I was looking for when I searched the forum.

Without knowing 'tecky' (sic) things like the size of your system in kW, which way it faces, the roof pitch and some non-techy things like where you are in the country, how much electricity you use when the sun is shining etc it's impossible to predict how much you will save.

Don't mean to be rude, but you seem to have been expecting some simple on-size-fits-all answer that doesn't exist.

Plenty of people post details of quotes they get here and get simple opinions on whether they are good value or not. Seems you've gone for something that solves a problem you don't have (shading) and paid more than you could have and come back to tell us how well you've done.

Ed

orrery

Misslayed wrote: »

I did come to the forum, and the high level of tecky talk was no use to me at all. Too much information.

People have been a little unkind, so lets try to make it helpful instead.

It would be worth persevering a little with the techie bit, simply because knowing more about your system will help you make more of it and achieve greater savings.

It has already been discussed on this forum, but it is worth understanding a few simple facts ...

Assuming your connection into your house electricity is the the same as most people, and assuming your tariff works in the same way too, then:

• you get paid nothing extra for exporting what you generate (don't get confused with the sales talk of 50% export - that is just an assumption made and is paid on what you generate, not what you export), so it is best if you can make maximum use of the free power you are generating, so...
• always try to use powerful appliances (washing machines, dishwashers, kettles etc) when it is sunny, and...
• only use them one at a time - not on all together (once you've used what you are currently generating, the rest is imported and you pay for it).
• don't try to displace cheaper forms of heating (e.g. gas) by using solar electricity, as you are likely to just end up importing more at a much higher cost than you pay for gas (unless you use an automatic diverter, like a solarImmersion or similar)

amitagarwal

Hello


Does anyone know about Green Energy Nationwide Ltd (also known as Green Energy NW Ltd) who have taken my deposit and not come back for work in last 3 weeks. They have been not responding to any phone and email.


Thanks

CrazyCol

First as someone looking to install I would like to thank all the contributors for the help & advice I have been following, it is much appreciated. Tech level is exactly right for me & been invaluable.
Secondly I am much closer finalising my system from 1 of 2 suppliers,
1 for 14 LG mono X 280W panels plus Growatt inverter. 10 yr warranty on each, plus monitoring via wifi. app.
2nd for 16 X JA solar 250W panels with built in edge monitoring plus solar edge inverter complete with 10/20yr warranties resp. wifi via solar edge + solo II monitor.
Not much in it on price really more about the quality of the 2 systems.
I know solar edge not really required(no shading) but improved individual panel monitoring + better inverter + it's warranty + local display
versus
Better quality LG panels, only 14 to fit, less complex with no edge monitoring to go wrong. Though plenty of space for 16X250W
What can you advise about the relative merits please