Patent ID: 9620663
Date: 2017-04-11
CPC Classifications: F24S,H01L,H02S,Y02E

Claim:
1. A system for detecting an optimal timing for cleaning duty solar panels which include photovoltaic cells configured for generating electricity, the system comprising: a simulation sensor which includes photovoltaic cells identical to the photovoltaic cells of the duty solar panels, wherein the simulation sensor is configured to generate a simulation electrical signal which simulates electricity signal generated by the duty solar panels, and the simulation sensor and its photovoltaic cells are separate and distinct from the duty solar panels and their photovoltaic cells; a reference sensor which includes photovoltaic cells identical to the photovoltaic cells of the duty solar panels and same area as the simulation sensor, wherein the reference sensor is configured to generate a reference electrical signal which simulates electricity signal generated by the duty solar panels in a clean condition, and the reference sensor and its photovoltaic cells are separate and distinct from the duty solar panels and their photovoltaic cells and from the simulation sensor and its photovoltaic cells; and protection means configured to selectively expose the reference sensor for a specified period of time, wherein the system is configured to operate independently of the duty solar panels being monitored by comparing the simulation signal and the reference signal when the reference sensor is uncovered and providing an indication that the duty solar panels should be cleaned if a difference between the simulation signal and the reference signal exceeds a predefined level.