NASA Surface meteorology and Solar Energy - Available Tables for Sri Lanka

NASA Surface meteorology and Solar Energy - Available Tables


Parameters for Sizing and Pointing of Solar Panels and for Solar Thermal Applications:
Monthly Averaged Insolation Incident On A Horizontal Surface (kWh/m2/day)Lat 7
Lon 80 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual
Average
22-year Average 4.69 5.61 6.07 5.54 5.09 4.70 4.74 4.93 4.99 4.66 4.32 4.28 4.96
Minimum And Maximum Difference From Monthly Averaged Insolation (%)Lat 7
Lon 80 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Minimum -19 -40 -16 -16 -8 -15 -15 -11 -18 -12 -20 -23
Maximum 19 19 13 7 9 15 17 14 18 27 14 21
Parameter Definition
Monthly Averaged Diffuse Radiation Incident On A Horizontal Surface (kWh/m2/day)Lat 7
Lon 80 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual
Average
22-year Average 1.86 1.90 2.02 2.23 2.19 2.15 2.17 2.25 2.26 2.13 1.95 1.84 2.08
Minimum 1.62 1.48 1.74 2.15 2.10 2.04 2.04 2.13 2.09 1.87 1.86 1.64 1.90
Maximum 1.93 2.03 2.23 2.33 2.23 2.16 2.18 2.27 2.28 2.14 1.94 1.85 2.13
22-year Average K 0.50 0.56 0.58 0.52 0.49 0.46 0.46 0.47 0.48 0.46 0.46 0.47 0.49
Minimum K 0.41 0.34 0.49 0.44 0.45 0.39 0.39 0.42 0.39 0.41 0.36 0.36 0.40
Maximum K 0.60 0.67 0.65 0.56 0.53 0.53 0.54 0.54 0.56 0.59 0.52 0.57 0.57
NOTE: Diffuse radiation, direct normal radiation and tilted surface radiation are not calculated when the clearness index (K) is below 0.3 or above 0.8.
Parameter Definition