Solar Disinfection: analyses and results of NASA's Daily Series of Insolation Data for Predicting Exposure Period in Nigeria

Published: 26-01-2021| Version 2 | DOI: 10.17632/jgf2y682br.2
Ekene Nwankwo


The operation of solar disinfection (SODIS) systems requires variable exposure period depending upon the available radiation energy. The uncertainty arising from variable exposure period can be resolved by using probability methods. This study presents a methodology for determining SODIS exposure period (days) by analysing the occurrence frequency of the disinfection threshold in a daily series of radiation data. To do this, the exposure period was interpreted as the number of consecutive exposure days until the occurrence of a day whose solar irradiance is greater than the disinfection threshold. Thus, the exposure period required for at least a single occurrence of the disinfection threshold could be estimated with a certain probability of success, depending on the confidence level or risk of underexposure one is willing to take. The folder “NASA's Insolation Data and the Simulated 5-h Average Peak Intensity Equivalence (3600 Datasets)” contains the 3600 (300 times 12) datasets in Excel format representing 300 locations and 12 months in Nigeria. The Excel files are named according to the latitude and longitude and the month the datasets represent. The 5-h average peak intensity equivalence was computed from NASA’s insolation data using the algorithm described in the journal paper associated with this data. The folder “The Results of Pettitt's Homogeneity Test” contains an Excel file and a sub-folder (Homogenous Datasets). The Excel file contains the result of Pettitt’s homogeneity test. The Excel files in the sub-folder “Homogenous Datasets (3600 Datasets)” contains either the same dataset as the files in “NASA's Insolation Data and the Simulated 5-h Average Peak Intensity Equivalence (3600 Datasets)” if the dataset is homogeneous or the longer homogeneous section of the dataset if the dataset is not homogeneous. The datasets in “Homogenous Datasets (3600 Datasets)” were used for the analyses and the prediction of the exposure period. The folder “The Results of the Validation Experiment” contains an Excel file and two sub-folders. The Excel file is the result of the validation experiment reported in the journal paper associated with this data. Each dataset in “Homogenous Datasets (3600 Datasets)” was divided into two halves for validation purposes. The two subfolders contain the first half and the second half of the datasets.