| Mittlere tägliche Globalstrahlung auf horizontale Flächen [kWh/m2/d] | ||||||||||||
| Station / Monat | Jan | Feb | Mär | Apr | Mai | Jun | Jul | Aug | Sep | Okt | Nov | Dez |
| Norderney | 0.56 | 1.30 | 2.60 | 4.27 | 5.13 | 6.02 | 5.45 | 4.75 | 3.06 | 1.66 | 0.74 | 0.44 |
| Hamburg | 0.52 | 1.13 | 2.23 | 3.55 | 4.67 | 5.44 | 4.82 | 4.34 | 2.79 | 1.49 | 0.67 | 0.40 |
| Braunschweig | 0.63 | 1.16 | 2.24 | 3.43 | 4.65 | 5.20 | 4.77 | 4.21 | 2.79 | 1.50 | 0.70 | 0.42 |
| Braunlage | 0.74 | 1.34 | 2.40 | 3.51 | 4.42 | 4.95 | 4.79 | 4.16 | 2.78 | 1.67 | 0.76 | 0.51 |
| Berlin | 0.61 | 1.14 | 2.44 | 3.49 | 4.77 | 5.44 | 5.26 | 4.58 | 3.05 | 1.59 | 0.76 | 0.46 |
| Bocholt | 0.64 | 1.20 | 2.18 | 3.78 | 4.89 | 4.75 | 4.14 | 3.52 | 2.71 | 1.63 | 0.79 | 0.44 |
| Gelsenkirchen | 0.60 | 1.23 | 2.10 | 3.45 | 4.69 | 4.44 | 4.31 | 3.78 | 2.68 | 1.65 | 0.78 | 0.48 |
| Aachen | 0.69 | 1.34 | 2.29 | 3.61 | 4.75 | 5.00 | 4.82 | 4.26 | 3.06 | 1.76 | 0.88 | 0.54 |
| Bonn | 0.72 | 1.33 | 1.79 | 3.33 | 4.82 | 4.38 | 4.15 | 3.63 | 2.76 | 1.67 | 0.84 | 0.53 |
| Trier | 0.72 | 1.47 | 2.52 | 3.88 | 4.88 | 5.25 | 5.27 | 4.43 | 3.31 | 1.79 | 0.84 | 0.56 |
| Geisenheim | 0.70 | 1.22 | 2.07 | 3.59 | 4.72 | 4.85 | 4.52 | 4.07 | 2.87 | 1.52 | 0.77 | 0.54 |
| Freiburg | 0.76 | 1.34 | 2.51 | 3.59 | 4.71 | 5.20 | 4.83 | 4.55 | 3.46 | 1.92 | 0.97 | 0.72 |
| Nürnberg | 0.70 | 1.42 | 2.27 | 3.07 | 5.66 | 5.84 | 5.03 | 4.52 | 2.99 | 1.90 | 0.87 | 0.65 |
| Würzburg | 0.82 | 1.60 | 2.68 | 4.04 | 5.03 | 5.54 | 5.34 | 4.49 | 3.53 | 1.94 | 0.92 | 0.65 |
| Weihenstephan | 1.07 | 1.83 | 2.96 | 4.11 | 5.08 | 5.39 | 5.46 | 4.60 | 3.70 | 2.23 | 1.18 | 0.83 |
| Hohenpeissenberg | 1.38 | 2.05 | 3.17 | 4.15 | 4.89 | 5.13 | 5.40 | 4.62 | 3.85 | 2.62 | 1.43 | 1.12 |