Variability of measured Global Horizontal Irradiation throughout Qatar

摘要: Abstract This paper presents a study of up to six years ground measurements Global Horizontal Irradiation (GHI), the total solar radiation arriving on horizontal surface, collected by 12 automatic weather stations throughout Qatar. The year-to-year and monthly variations daily GHI are calculated for each station; average found is 5.80 kWh/m 2 /day, 2116 kWh/m /year. Spatially, averages through country vary with relative standard deviation 4% respect averages; in general, higher south north regions Qatar, except at northern tip country, lower values mainly central latitudes, close industrial areas. Frequency distributions present two peaks, which correspond distinct periods year: one from March September, most frequent around 7 kWh/m October February, centred 4.5 kWh/m /day. A similar can be advisable other areas comparable climate or topographies, since these seasons might also and, if found, should considered design implementation photovoltaic-based systems. Finally, clearness index (ratio ground-level top-of-the-atmosphere GHI) presented location Qatar as whole compared longer-term satellite-based values. annual 0.64, indicative clear-sky conditions year. fuel photovoltaic systems, so its fundamental such applications, provides reference derivation data models satellite observations.