04/08/2026
Performance Ratio ek fraction hai. Industry poora dhyaan numerator pe deti hai, aur denominator ko kabhi audit nahi karti.
Numerator — actual generation. Yeh metered hai, invoiced hai, disputed hai, monthly reconcile hoti hai. Iske peeche sab lage rehte hain.
Denominator — measured irradiance. Yeh ek sensor se aata hai. Ek pyranometer, ek mast pe, poore plant ke liye. Aur uska output kabhi verify nahi hota.
Ab yahan asymmetry samajhne wali hai. Agar pyranometer measured irradiance kam report kare, to denominator chhota ho jaata hai — aur PR badh jaata hai. Yaani sensor ka error plant ko behtar dikhata hai, kharab nahi. Under-reading sensor ek flattering error hai.
Aur denominator ko galat karne ke kai raaste hain: dome pe soiling, calibration sensitivity drift, levelling error (tilt se cosine response badal jaati hai), mast position jo array ke representative nahi hai, structure ya vegetation se partial shading, thermopile sensor mein thermal offset, aur sensor class jo plant ke reporting requirement se match nahi karta.
Sabse important baat yeh hai. Jis din site dusty hai, us din dono cheezein soil hoti hain — modules aur pyranometer dome. Modules soil hone se generation girti hai, to PR girna chahiye. Pyranometer soil hone se measured irradiance girti hai, to PR badhta hai. Do effects ek doosre ko partially cancel kar dete hain.
Iska matlab: soiling loss PR mein dikhna band ho jaata hai. Jo parameter aap soiling detect karne ke liye dekh rahe hain, wahi soiling se masked ho jaata hai.
Aur ek structural point — pyranometer ko clean aur maintain karne wali party usually wahi hai jiski performance PR se measure hoti hai. Yeh self-audit possible nahi hai. Isme koi bad intent zaroori nahi, structure hi aisa hai.
Teen cheezein maango: pyranometer ka last calibration certificate, cleaning log with dates, aur sensor ka level check record.
EnergyYield SolarEPC EngineeringFacts
