Temperature coefficient is the most critical specification for hot climates: Premium panels with coefficients of -0. 29%/°C can maintain 85-90% efficiency in extreme heat, while standard panels may lose 15-20% efficiency at the same temperatures. In commercial solar street lights and other off grid lighting system applications, solar panels are continuously exposed to intense outdoor sunlight. Proper installation can improve performance. Hot spots are regions of extreme heat that influence solar cells by absorbing energy rather than producing it. As a result, the panel gets heated and overloaded, which leads to a short-circuit that lowers output efficiency overall while hastening material deterioration. Hot spots can origin, if one solar cell, or just a part of it, produces less carrier compared. However, when one or more cells in a string cannot produce enough current, the situation is known as the hotspot effect. How to Detect Solar Panel Hotspots? Solar panel.