Experimental investigation of soiling losses and a novel cost-effective cleaning system for PV modules

Abstract

Dust accumulation significantly reduces the efficiency of a photovoltaic (PV) module, and the unavailability of an economical and efficient cleaning solution is the persistent problem. Therefore, the focus of this study is to investigate the effect of dust on PV performance and propose a novel cleaning system for the removal of dust from the PV modules. The outdoor experiment is conducted on the monocrystalline (mono-PV) and polycrystalline (poly-PV) PV modules. Each experimental set contains two PV modules (mono-PV and poly-PV), one set is cleaned every day and the other set left uncleaned throughout the experiment. The cleaning of the PV module is performed using pressurized water, sprayed through a flat-fan nozzle to clean the front surface. The wastewater is collected, filtered and directed back to the storage tank. The cleaning system has a water recovering capacity of 55% and a water requirement of 1.8 L per m2 of PV area. It has been analyzed and observed that the output power of the mono-PV module and poly-PV module has decreased by 16.16% and 11.54%, respectively after one month with the dust deposition density of 4.6 g/m2. The cleaning process improves the efficiency of the PV modules to 98% of it’s original value in 35 s of operation. It has been evaluated that the proposed cleaning system is cost-effective for commercial sized PV modules. Furthermore, the mono-PV module (400-watts) and poly-PV module (355-watts) should be cleaned within 85 days of dust accumulation for optimum energy usage.