This study is focused on technical and economic analysis of cleaning protocol of Photovoltaic panels in power plants as function of dust density translated into soiling level. Indeed, the accumulation of dusts on PV panels influences the conversion efficiency of PV modules. The design and operating simulation have been carried out with specific computer calculation code "Helioscope". The effects of soiling on these clean power plants have been studied for power capacities of 1 and 5 MW and two types of PV panels' technologies: Cadmium Telluride (CdTe) Thin Films and Monocrystalline Silicon (Mono-Si). By considering databases of environmental dust loads, soiling level of 10 and 15% allows to be close to conditions of two studied locations in Sahara desert of Algeria. The analysis of simulations results for performance index (PR) showed remarkable diminution when PV panels' fields are soiled. For estimating cleaning cost of PV fields, the design and simulations of PV power plants in Algerian Sahara sites of Adrar (1 MW) and Ouargla (5 MW) demonstrated the existence of soiling threshold allowing cleaning profitability which is situated around 7% in term of minimal level. Besides, it has been shown that the PV panel technologies are affecting sensibly this level and then can be decisive in the choice of the type of PV modules to install. Also, the feed in tariff (FIT) is critical on this soiling threshold. (C) 2017 Elsevier Ltd. All rights reserved.