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Solar Insolation Data for US Cities

Solar insolation data for many large U.S. cities.

Find the city closest to you on the list below – or use this USA map of insolation and PV potential for greater accuracy.

Always use the low value for your calculations when designing an off-grid system to make sure your battery bank is prepared for the worst case scenario!

State City High Low Avg
AK Fairbanks 5.87 2.12 3.99
AK Matanuska 5.24 1.74 3.55
AL Montgomery 4.69 3.37 4.23
AR Bethel 6.29 2.37 3.81
AR Little Rock 5.29 3.88 4.69
AZ Tucson 7.42 6.01 6.57
AZ Page 7.30 5.65 6.36
AZ Phoenix 7.13 5.78 6.58
CA Santa Maria 6.52 5.42 5.94
CA Riverside 6.35 5.35 5.87
CA Davis 6.09 3.31 5.10
CA Fresno 6.19 3.42 5.38
CA Los Angeles 6.14 5.03 5.62
CA Soda Springs 6.47 4.40 5.60
CA La Jolla 5.24 4.29 4.77
CA Inyokern 8.70 6.87 7.66
CO Granby 7.47 5.15 5.69
CO Grand Lake 5.86 3.56 5.08
CO Grand Junction 6.34 5.23 5.85
CO Boulder 5.72 4.44 4.87
CT Hartford 5.40 3.33 4.74
DC Washington 4.69 3.37 4.23
FL Appalachicola 5.98 4.92 5.49
FL Belie Is. 5.31 4.58 4.99
FL Miami 6.26 5.05 5.62
FL Gainesville 5.81 4.71 5.27
FL Tampa 6.16 5.26 5.67
GA Atlanta 5.16 4.09 4.74
GA Griffin 5.41 4.26 4.99
HI Honolulu 6.71 5.59 6.02
IA Ames 4.80 3.73 4.40
ID Boise 5.83 3.33 4.92
ID Twin Falls 5.42 3.42 4.70
IL Chicago 4.08 1.47 3.14
IN Indianapolis 5.02 2.55 4.21
KN Manhattan 5.08 3.62 4.57
KN Dodge City 4.14 5.28 5.79
KY Lexington 5.97 3.60 4.94
LA Lake Charles 5.73 4.29 4.93
LA New Orleans 5.71 3.63 4.92
LA Shreveport 4.99 3.87 4.63
MA E. Wareham 4.48 3.06 3.99
MA Boston 4.27 2.99 3.84
MA Blue Hill 4.38 3.33 4.05
MA Natick 4.62 3.09 4.10
MA Lynn 4.60 2.33 3.79
MD Silver Hill 4.71 3.84 4.47
ME Caribou 5.62 2.57 4.19
ME Portland 5.23 3.56 4.51
MI Saulte Ste. Marie 4.83 2.33 4.20
MI E. Lansing 4.71 2.70 4.00
MN St. Cloud 5.43 3.53 4.53
State City High Low Avg
MO Columbia 5.50 3.97 4.73
MO St. Louis 4.87 3.24 4.38
MS Meridian 4.86 3.64 4.43
MT Glasgow 5.97 4.09 5.15
MT Great Falls 5.70 3.66 4.93
MT Summit 5.17 2.36 3.99
NM Albuquerque 7.16 6.21 6.77
NB Lincoln 5.40 4.38 4.79
NB N. Omaha 5.28 4.26 4.90
NC Cape Hatteras 5.81 4.69 5.31
NC Greensboro 5.05 4.00 4.71
ND Bismarck 5.48 3.97 5.01
NJ Sea Brook 4.76 3.20 4.21
NV Las Vegas 7.13 5.84 6.41
NV Ely 6.48 5.49 5.98
NY Binghamton 3.93 1.62 3.16
NY Ithaca 4.57 2.29 3.79
NY Schenectady 3.92 2.53 3.55
NY Rochester 4.22 1.58 3.31
NY New York City 4.97 3.03 4.08
OH Columbus 5.26 2.66 4.15
OH Cleveland 4.79 2.69 3.94
OK Stillwater 5.52 4.22 4.99
OK Oklahoma City 6.26 4.98 5.59
OR Astoria 4.76 1.99 3.72
OR Corvallis 5.71 1.90 4.03
OR Medford 5.84 2.02 4.51
PA Pittsburgh 4.19 1.45 3.28
PA State College 4.44 2.79 3.91
RI Newport 4.69 3.58 4.23
SC Charleston 5.72 4.23 5.06
SD Rapid City 5.91 4.56 5.23
TN Nashville 5.20 3.14 4.45
TN Oak Ridge 5.06 3.22 4.37
TX San Antonio 5.88 4.65 5.30
TX Brownsville 5.49 4.42 4.92
TX El Paso 7.42 5.87 6.72
TX Midland 6.33 5.23 5.83
TX Fort Worth 6.00 4.80 5.43
UT Salt Lake City 6.09 3.78 5.26
UT Flaming Gorge 6.63 5.48 5.83
VA Richmond 4.50 3.37 4.13
WA Seattle 4.83 1.60 3.57
WA Richland 6.13 2.01 4.44
WA Pullman 6.07 2.90 4.73
WA Spokane 5.53 1.16 4.48
WA Prosser 6.21 3.06 5.03
WI Madison 4.85 3.28 4.29
WV Charleston 4.12 2.47 3.65
WY Lander 6.81 5.50 6.06

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