There's not enough sun where I live
If you can get a sunburn where you live, you can make productive use of the sun. Conditions at your specific property may not be suitable for solar energy (due to trees, adjacent structures, etc) but every region of the world has a workable solar resource. The Germans recognized this fact and have become the world leading country of installed PV systems despite a well deserved reputation for having cloudy weather. You'll see from the map above that all of the US has a much better solar resource than that of Germany.
A basic principle of solar electric production is that colder weather boosts voltage output of modules so a clear cold day in the winter could lead to the greatest output of the year. On the solar water heating side of things, lower ground water temperatures in the north make solar thermal even more attractive from an energy economics angle than in sunny, warmer places. The bottom line is that solar works everywhere. Residents of every part of the United States are missing out on a great opportunity if we don't take a hard look at the potential for solar energy sytems in our area.