"It works in California" means that it is potentially viable elsewhere. As others have pointed out: California is not the sunniest, not the simplest roads, mos

"It works in California" means that it is potentially viable elsewhere. As others have pointed out: California is not the sunniest, not the simplest roads, most consistent weather, or the most favorable regulatory environment. If it works in California then it will probably work elsewhere. AND more importantly, if it doesn't work in California then it's probably not going to work anywhere else.