It's true and a Big Problem on my Monitor Data Logging Rambos 😎 They assumed the best and when I do upgrade work always look 1 year and 2 year back !!! Than they see ,also after 1 week only ( so they think No major improvement ). So I keep on telling them let's assume March 2025 to look at starting January to May wether it fits in between. No ,always the same response - not better some are "complaining" it's worse than a year before and We did that already Andreas - no improvement that time What they miss out is weather anomalies as You describe +- 2-3 months of . But I say there's every year potatoes and strawberries ..... So look up highest peak! Better Mppt value We are in "transitioning" I had a 180 MW site and I told them to check kWh/kWp. Nope they kept on checking Irradiance or PR value ,which is kind of a Gimmick at the end of the year. I could higher the kWh/kWp at the end of the year. And instead having only 135 MW online ,I pushed the values as high as 175 MW for several hours after fine-tuning !!! So keep on telling them We made BIG progress ,Inverters are All online producing 1-3 hours earlier than before and have the highest Peak Performance going almost 100% output . After 1-2 month it became clear the Plant was outperforming previous years ,starting from March . But the Nonsense from Monitoring Team never stopped ,weather All of a sudden was better , that's only for these 1 or later 2 months than 3 months etc etc. Some guys do the same job for 8-10 years never tried to finetune and are reluctant to learn something new - sadly Of course that's not overall but again 80% of my work are underperforming systems and they are onsite like "headless chicken". I had guys which confirmed over and over not working strings but exactly at 9 am . Those were mounted on east or west facing inclination . In some cases they "outperformed" later the other strings or even inverters. But he was "booking" the numbers since 8 years like clockwork ,never once went to site and gave out the same ticket for years.

Absolutely You can only learn from the Best and Questions they ( still ) have...... I love it .....

@Jan Mastny https://www.linkedin.com/posts/sebastian-ewert_energiewende-zaeuhler-activity-7404425959216660481-vbAj?utm_source=share&utm_medium=member_android&rcm=ACoAAAIq-W0B9doX5ZyoUdW0LH1OIL-04-rauPY

@Jan Mastny some tried 1,5 years to get a smart meter and gave up . Even Munich City Power has its problem with some providers ..... Thats on purpose ,as they make No Money even pay Money out - who wants that So increasing monthly "metering costs" etc etc

Yeah, I had this issues in several Plants ,Spain ,Rumania , Ireland ..... It is either the Protocoll or PPC Controller which is asking reactive power and curtailement at the same time. Inverters sometimes wrong Grid Codes ,wrong software ,different software packs between dataloggers and inverters "creating" a YoYo Effect. By that the inverters getting "package" thinking they are alone , so when some invertets go down - others go up which makes AC unbearable. Some fix it with a -10% curtailement in advance to cope with changes other use fixed values for different Transformers so All of them go down to fixed value and than slowly increase . Its the Controller is to slow with All inputs , it creates 30% for one while others are still at 90% output - till they get the Signal Your thought is correct when You stop Controller .....its an ongoing problem ,especially for inverters who can malfunction

The problem differs ,it's about fine-tuning your inverters to "surroundings" - it doesn't help to have the best components and the Utility Grid "is a Beast ". Also if You feedin LV side of a factory ,You need to help out the factory with harmonics,pf ,cost , reactive power . If You won't stabilize the Grid no one will help You out. As You correctly stated ,it was working fine ,but those setpoints must be revaluated - in my sites I do it every 6 months ,could be taps settings of Transformer or setpoints Mppt ,local ,global, sun ,cloudy ..... Keep it simple , but stay "afloat". Don't react when it's to late .

No its not your right. Most Investors or EPCs try to get overboard and use same products ,same inverters and sadly make same mistakes ....... Some are banklisted as Tier 1 and it definetly still makes sense what badge You receive. Still not All are of same quality ,similar but some are from old lines vs newer lines or even different Cities. Good example Hotels or Flights although 5* rated are not of same quality ..... On another note the BOM list has nothing to say about Transport ,Installation or Output of the System built. With always quicker ,quicker and deadlines which cannot be fulfilled without Tricks and some Transportation issues of Transformers or BESS Project is dead on arrival. The more output ,the less quality . In my days in manufacturing many used durable Silicon material with hardened frames at factory vs kind of still curing Silicone during freight . Sometimes modules cured skew ,other times it was fine or ok. Inventory ,Warehousing is an issue - always was . Producing onetime another !!!

You get some real "PV freaks" who know everything about everything ,some even design their own system. Naturally they know nothing about PV but All other neighbors installed PV so he also installs it. All comes towards feedin or like Germany already "matured market " in self consumption. In Germany many start with 2-4 modules called balcony solar which is cheap and almost anywhere available. Once they see it working they get bigger systems. Not every house roof is South facing ,but East West works wonders . It All depends on the Country . In South Africa 2003-2009 I sold PV systems only with backup supply / battery . There was No feedin ,but You had your Internet running ,Lights on and dedicated plugs like fridge ,freezer etc etc Money back in 1 day. Via Feedin or saving like 100 years But loosing 8 hours and longer power supply or sending your employees home or cannot phone - the math added up