Normal Incident Solar Radiation Atlas
These data were originally downloaded from the National Renewable Energy Laboratory (NREL) web site http://www.nrel.gov/gis/data_solar.html in units of kilowatt-hours per square meter per day and were converted to Langleys per day. 1 Langley per day = 1 calorie per square centimeter per day. or 1 Langley per day = …