it's a marginal step improvement to turn a really bad system into a slightly less bad, but highly complex and timeconsuming system that's still only accurate to within 10% or so, and is even worse for east or west facing systems.
and yet we're not allowed to give any prominance to far more accurate methods of working this out because MCS has decided their remit is to ensure the industry is leveled down to the level of the most basic installer rather than encouraging excellence and accuracy.... or with the greatest of respect to the 2 main authors, they are both electrical engineers, and devising the best method of calculating accurate performance estimates and shading impact assessments doesn't really fall into an electrical engineers main skill set IMO.
The development of this entire performance estimation method should have been widened out to the industry and consulted upon properly to produce a method that actually works properly, or at least wording it so that those of us who already have developed and use a suitably accurate method are allowed to use that instead of their method. Not being funny, but this actually is directly within my academic skill set (and I'm sure a fair few others as well), and I did makes these points to one of the 2 lead authors in advance, and the offer to assist was made but not taken up.
This is like some sort of half arsed student project that we're all being expected to follow despite knowing how badly flawed it is. It's frankly laughable that they actually use PVGIS satelllite data to produce the average tables for each region, but won't accept us using PVGIS as it's intended, to provide highly accurate localised performance data rather than data with a >15% regional variance around the average data point they've used (in our region).
I also reckon that as it wasn't consulted upon properly, then MCS have no legal right to force this methodology on the industry... but then I'm not a lawyer and can't afford to pay one to confirm this right now.
/rant.
