MCS PV Output Estimation and Shading

[Gavin A]

Thanks for the document, Gavin. It looks comprehensive and I wish you both a good trip to London. (It might have been a good idea to locate Skegness, Sheffield and Skipton on the map because the suits in Whitehall probably don't travel much north of Watford so wouldn't be so clued up about Butlins at Skeggy).

I did think about that, but then decided that if any of them actually are that ignorant of the north, then it probably wouldn't be a bad idea to smoke them out.

emails sent

 

[BruceB]

Well done both of you. I have sent some comments and a note of support in separate emails
Regards
Bruce

 

[Gavin A]

As Jesus said, "it is easier for a camel to go through the eye of a needle, than for a humble solar installer to change the mind of the MCS steering committee."

more later maybe... got some eating and drinking to do tonight.

 

[The Solar King]

An interesting meeting. Whilst not a win, some of the comments made are very useful. I am sure that our interpretations will differ somewhat due to our differing start points and expectations.

Like Gavin I have some R&R to do. Surprised I managed to function on 4 1/2 hours sleep night before. (They appeared to be resurfacing Birmngham to delay my journey yesterday evening).

Thanks to Gavin for his invaluable input.

 

[SolarCity]

Well done fellas. Fair play for actually trying to do something.

 

[solarsavings]

Just seen this. Thanks both of you.

 

[Energetic]

Just seen this thread, apologies, too late but you have my support. Will email details.

Thanks for all your efforts.

e

 

[Gavin A]

No time for details now, but I'm still interested in gathering support for this - basically we got knocked back at the meeting, but have got consent to effectively set up a working group to investigate the subject further and report back.

Got to get the terms of reference agreed, but I'm actually thinking that this could be a pretty good option longer term.

 

[The Solar King]

We got knocked back, but the absurdity of the situation was further exposed. I felt as if I was listening to a despot who had created a logic that could be followed to justify committing an atrocity. Whilst logical it never makes it right. In their eyes what ever you say is wrong. Continuance means this will all end in tears with the scheme in disrepute.

I could not believe my ears when at one stage the Chair stated it had been designed so it could be used by a salesman to sell on the day.....

I am not back home yet, but will post more on my return. To use a military analogy, we have drawn their fire, know their positions and have exposed their weaknesses.

 

[SolarCity]

I could not believe my ears when at one stage the Chair stated it had been designed so it could be used by a salesman to sell on the day.....

He really said that?

In that case, what IS the MCS for? Because if that is what their position is then it is simply dumbing down a complicated industry.

 

[Gavin A]

The chair of the MCS working group uses deal on the day salesmen, therefore the method was designed to be usable by sales men working on site.

The other key member of the group who seemed to be able to block anything proposed, basically has criteria that it has to be easily for assessors to verify and replicate.

So essentially we have a policy that is aimed at being very simplistic, and easy to check that the method has been followed correctly. Anything to do with accuracy plays second fiddle to those 2 points.

As someone else in the meeting said.... 'if a representative of a consumer organisation was in this meeting, what would they be saying about this?'

 

[SolarCity]

As someone else in the meeting said.... 'if a representative of a consumer organisation was in this meeting, what would they be saying about this?'

There it is in a nutshell. What exactly IS the MCS for?

I will be absolutely f'ing fuming if (when) I get pulled up in my MCS evaluation for essentially using a method which is not compliant as it is too complex for a f'ing salesman to use.

 

[The Solar King]

I will post more bits in dribs and drabs on this.
Here is the disclaimer we are proposing to use in all our customer quotations:

"We are obliged under the terms of our membership of the Microgeneration Certification Scheme to provide the following estimate of performance based on a specified manual method. This estimate will be that shown on the registration document for your system. This method may produce inaccurate results for the following reasons:

• It takes insufficient account of geographic location.
• There may be significant variance in irradiance at your location in comparison to that given in the data provided.
• The estimate takes no account of the performance of equipment specified or its ability to mitigate the effects of shading.
• It is prone to further inaccuracy in estimating the effects of shading due to human error.

Following the mandatory performance estimate is one prepared using expert system software specific to your location, based on the survey undertaken, and taking full account of the equipment specified. Any financial analysis provided is based on this figure. In our opinion this better reflects expected performance and is subject to the standard disclaimer given."

I would welcome any comments on how this can be honed to improve it.

 

[TedM]

"Any financial analysis provided" - don't you always provide an analysis? If so this should be "The financial analysis provided".

"In our opinion this better reflects expected performance" sounds a little weak and will just prompt a request for justification. I would use "Data from existing customers have shown that this method better reflects expected performance." and actually have the data to back that up, possibly as an anonymised separate report you can give the customer.

"... and is subject to the standard disclaimer given." I would have this as a separate sentence and use a section/paragraph reference to avoid any ambiguity. "This analysis is subject to the standard disclaimer given at x.xx."

 

[whinmoor]

Saw this job recently. Wonder how it would have scored using the sunpath diagram and if it's performing in line with the installer's prediction . It may have been better to install on the other roof surface.