Actually in California a solar panel owner already does have solar rights. http://www.leginfo.ca.gov/cgi-bin/displaycode?section=prc&group=25001-26000&file=259

Actually in California a solar panel owner already does have solar rights. http://www.leginfo.ca.gov/cgi-bin/displaycode?section=prc&group=25001-26000&file=25980-25986 http://www.leginfo.ca.gov/cgi-bin/displaycode?section=prc&gr... "25982. After the installation of a solar collector, a person owning or in control of another property shall not allow a tree or shrub to be placed or, if placed, to grow on that property so as to cast a shadow greater than 10 percent of the collector absorption area upon that solar collector surface at any one time between the hours of 10 a.m. and 2 p.m., local standard time." There are a number of exceptions later in the act, including a notification requirement. However, once a solar system is installed - a neighbor can't cause the system to be shaded with impunity.