Ahmed Alami Merrouni

Experimental Investigation of Potential Induced Degradation (PID) Impact and Recovery on Crystalline Photovoltaic Systems

The present study focuses on the effects of PID on the performance of c-Si based solar PV panels installed on the mid-southwestern- Morocco for 3 years. The investigation has been divided into two parts: (i) The measurement of the power drop due to PID; (ii) since the PID is a reversible phenomenon, the polarity inversion technique has been used to evaluate the PID recovery. Electroluminescence (EL) images and electrical characteristics of investigated PV modules as the most accurate way of power loss analyzing have been conducted as a verification routine. Results show that the rate of power output drop due to PID is between 1 and 4%/years. Furthermore, the polarity inversion for one day can make this defect no more visibly detected (using EL inspection) and show an improvement in the module’s power output of 7.6%.

A Comparative Study on Hydrogen Production from Small-Scale PV and CSP Systems

The aim of this study is to simulate the hydrogen production from small scale solar photovoltaic (PV) and Concentrating Solar Power (CSP) technologies using 3 years averages of high quality solar irradiation data measured at ground level. To do so, a EuroDISH Stirling system and a PV plant with a capacity of 10 kWe have been designed and their electricity production were simulated under the climate of Bengrir, Morocco. Afterwards, the hydrogen production, via water electrolysis process, has been calculated for both technologies and the performances of each technology were assessed. Results show that Stirling dish produces more electricity than PV with an annual production of 20.7 MWh against 16.7 MWh. Similarly, the annual hydrogen production from the EuroDISH system is around 364 kg while is around 334,2 kg for the Stirling dish and PV respectively. Nevertheless, the electricity production from the Stirling dish is more expensive than from PV with an LCOE of 0,2909 €/kWh and 0,0928 €/kWh for the dish and PV respectively.

Evaluation of Different PV Prediction Models. Comparison and Experimental Validation with One-Year Measurements at Ground Level

At the early stage of photovoltaic plants feasibility study, the assessment of the power production and the technology performances is a necessity. To do so, engineers usually use software’s and prediction models. Plenty of models are available in the literature, nevertheless, the selection of the most suitable one to be use in a specific climate is a hard task since no study deals with the inter-comparison of the existing PV production models. In this paper, the output of 12 from the most used PV production models were evaluated and their accuracy has been assessed versus one-year real measurement data from a PV module in different time resolutions. Results show that four models (M1, M2, M3 and M4) are the most adequate models to simulate the PV performances under harsh climatic conditions (case study of Benguerir city, Morocco) with a minimum hourly RMSE of 7.07% during spring, 4.23% during summer, 7.56% in autumn and 10.11% in winter.

The uncertainty of the HelioClim-3 DNI data under Moroccan climate

The purpose of this study is to evaluate the uncertainty of the DNI satellite-derived data from HelioClim-3 against those measured at ground level by calculating the classical statistical performance indicators for different time resolutions (hourly, daily and monthly). Correlations between the errors and the Aerosol optical depth (AOD) data measured by an AERONET sun photometer station at the University of Oujda were performed. Results show that the DNI data derived from Helioclim-3 can be considered as acceptable for satellite data with an RMSE of 19.7 % and a bias of 7.9 % for the hourly data. HelioClim-3 systematically over-estimates the daily DNI sums for the investigated site. The correlation to AOD at 550 nm can only be one of the reasons for the deviation. Corrections or site adaptation could help to increase the accuracy of the data base for that pixel.The purpose of this study is to evaluate the uncertainty of the DNI satellite-derived data from HelioClim-3 against those measured at ground level by calculating the classical statistical performance indicators for different time resolutions (hourly, daily and monthly). Correlations between the errors and the Aerosol optical depth (AOD) data measured by an AERONET sun photometer station at the University of Oujda were performed. Results show that the DNI data derived from Helioclim-3 can be considered as acceptable for satellite data with an RMSE of 19.7 % and a bias of 7.9 % for the hourly data. HelioClim-3 systematically over-estimates the daily DNI sums for the investigated site. The correlation to AOD at 550 nm can only be one of the reasons for the deviation. Corrections or site adaptation could help to increase the accuracy of the data base for that pixel.