PV+ Grid Voltage Monitor

Martyn1981

I'm no where near you, but if it helps, and builds up some examples, my numbers for whole years, with all systems operational (against PVGIS targets) are:

2013 - 104%
2014 - 108%
2015 - 106%
2016 - 102%
2017 - 97% (current prediction if the rest of the year is average).

And just to be pedantic. If the average drop was 12-14%, which I don't believe, then if the PV+ was working as they claim, wouldn't you have gotten 86% + 17.2% (20% of 86%) = 103.2% of average annual target (120% of their stated national average of 86%)?

Martyn1981

If this helps, you can look at the Met Office anomaly maps. Scrolldown and select:
climate variable - sunshine
year - 2015 and 2016 (one at a time)
period - annual
map type 1981 -2010 (giving a comparison against 30yrs of data)

I'm no expert but it looks like 2016 was an ok year (95%-105% of average), whilst 2015 was better. However this is sunshine, and of course PV varies by temperature as well, but it may help you (in some way?)

Met Office anomaly maps

pinnks

To add to Mart's data, mine is:
2015 - 103% (first full year of both systems)
2016 - 101%
2017 - 100% (predicted based on year to date)

June 2016 was poor but the rest of the year not that bad as the overall position shows.

HTH

POLLY1133

Thank you so much for this information, I have a rep meeting me at my house on Thursday. They are looking at dirty panels (bird muck) and trees - although rainfall seems to keep the panels clean and I was up at 6 am and have monitored sunlight and there was no tree cover. Have been offered my money back if no improvement in a year's time but hoping to have an earlier resolution - no guarantee the company will be operating in a year's time! Again, I am very grateful to you!

Martyn1981

POLLY1133 wrote: »

Thank you so much for this information, I have a rep meeting me at my house on Thursday. They are looking at dirty panels (bird muck) and trees - although rainfall seems to keep the panels clean and I was up at 6 am and have monitored sunlight and there was no tree cover. Have been offered my money back if no improvement in a year's time but hoping to have an earlier resolution - no guarantee the company will be operating in a year's time! Again, I am very grateful to you!

All the very best for Thursday, but expect a lot of BS. If you want some extra ammo (be prepared), I've only given my panels a light wash every 2 or 3 years, but never really noticed any difference in performance, before or after.

The Energy Saving Trust, state:

Solar PV maintenance

Solar PV needs little maintenance – you'll just need to keep the panels relatively clean and make sure trees don't begin to overshadow them. In the UK panels that are tilted at 15° or more have the benefit of being cleaned by rainfall to ensure optimal performance. Debris is more likely to accumulate if you have ground mounted panels.

Once fitted, your installer should leave written details of any maintenance checks that you should carry out from time to time to ensure everything is working properly. This should include details of the main inverter fault signals and key trouble-shooting guidance. Ideally your installer should demonstrate this to you at the point of handover. Keeping a close eye on your system and the amount of electricity it’s generating (alongside the weather conditions) will familiarise you with what to expect and alert you to when something might be wrong.

The panels should last 25 years or more, but the inverter is likely to need replacing some time during this period, at a cost of about £800. Consult with your installer for exact maintenance requirements before you commit to installing a solar PV system.

And don't forget, whilst their claim that 2016 was an 86% year is clearly false, you should still have gotten 103.2% if their product had given you an uplift of 20% compared to 'average'.

So use real facts, figures, and their own claims against them.

zeupater

Hi

Information provided below is from PVOutput team 'United Kingdom' for the past 4 years. The team consists of 548 systems of which around 250 currently contribute on a daily basis therefore the sample size would prove statistically significant.

Average Generation kWh/kWp per day - percentage is 2016 vs year
2016 - 2.185
2015 - 2.243 - 97.4%
2014 - 2.276 - 96.0%
2013 - 2.209 - 98.9%

2016 when compared to the previous 3 year average resolves to a relative generation of 97.4% (2.185/((2.243+2.276+2.209)/3)), therefore a 'reasonable man' consideration would be that the reduction in generation due to irradiation conditions would be in the region of 2.6% which is certainly in line with the Met Office sunshine analytics figure provided by Martyn1981 in an earlier post.

It is important that POLLY1133 accurately compares 12 month generation post-installation for the same periods pre-installation in energy terms (kWh) as opposed to FiT payments as this removes tariff variance.

From information provided, annual payment reduced by £38 on a historical 'estimate' of £500. The annual uplift for FiT between 2015 & 2016 was 1.21%, therefore suggesting a 7.5% (38/(500*1.0121)) reduction in generation for this particular site which suggests that the FiT 'estimate' of £500 needs to be addressed urgently prior to any discussion with the vendor.

Irrespective of the accuracy of the data, it is clear that the provision of technology claiming to benefit generation is not performing in line with any technical or financial claims made.

Regarding 'bird muck' - considering that the generation periods being compared are annual, it is extremely unlikely (or even unreasonable) to assume or claim that a temporary reduction in output would resolve to anywhere near a 20.9% (1-((100*0.925)/((100x1.2)*0.974))) fall in annual generation against claims & expectations, this being due to the natural cleaning effect of rain combined with year on year long term averaging (birds tend to target panels on a regular basis!).

Regarding shading - it would be unreasonable to assume that shading related to trees would seriously impact annual generation (in the region of 25%) between two consecutive years without the shading source being extremely close to the array in question and the shade being almost immediately obvious.

It's no use in considering FiT income in any discussion unless claiming compensation for reduced generation. Accurate data on energy generation is needed to be gathered together urgently - this can either be from the quarterly submissions or downloaded directly from the inverter.

HTH
Z

POLLY1133

I shall digest the information you have kindly let me have and be prepared for them to come! They are coming Wednesday now but I shall stand my ground, I was certainly mis-sold! Thank you, thank you, thank you!

Merlin139

POLLY1133 wrote: »

I shall digest the information you have kindly let me have and be prepared for them to come! They are coming Wednesday now but I shall stand my ground, I was certainly mis-sold! Thank you, thank you, thank you!

If this system can do what it says then they should be able to show you proof backed up by facts and figures. The company that wanted to install one with me was Save Heat Energy. Based in Durham. because they installed my system I would be charged only £875.00

As I have said to them get 2 systems in houses next to one another. 1 with the system and 1 without. Then they could show you proof. I am still waiting after nearly a year for them to comeback to me. They won't because it dose not work!

My 3.975 kWh SolarEdge system produced:

2015 4158 kWh's
2016 4061 kWh's

I should also point out that I have a shading issue that causes a reduction of nearly 10% This being the reason I got a SolarEdge system with Micro Optimisers.

If they are not prepared to refund your money go down the small claims court route.

Hope you get the result that you want.

POLLY1133

Yes thank you Merlin139, it is the same company!

I have now calculated from the date of installation rather than quarterly readings

2015-2016 2885 kWh's - the year immediately before installation of PV +
2016-1017 2843 kWh's - the year from the date of installation

Enough said, readings would be ok had I not 'invested' in the PV+!

Gadget_Dave

I was contacted November 2016 about having PV Plus installed on my system by the original supplier. I've had my PV system installed since 2012. I listened to the salesman and what he had to say which made sense at the time and I agreed to give this a free trial, which he said if I am not totally satisfied after the 12 month trial they would remove it. The cost to have it installed was £1250.00 and I filled out a loan form for this underwritten by Ikano Bank. I was going to pay for this in cash but now looking at the data I've generated I've asked them to remove it and put my system back to how it was before. I am a saddo in the fact that since installation of my PV system I've methodically recorded daily figures for generation and was pleased to show this to the sales rep at the onset of the PV Plus upgrade discussions, basically saying i'll have the data to prove or not any potential improvements in generation. I have now produced a graph showing this data over the last 4 years, and includes the data after the PV Plus installation, the graph clearly shows no improvement whatsoever and therefore I will not be paying the fee.