My in-laws had a solar hot water heater in Seattle and the damn thing worked pretty well. We looked at solar here at our new place but the neighboring trees made it marginal.

Our kids new house in Irvine CA has solar electricity on the roof plus sub-irrigation for water. Like Rivrguy says, it is amazing he places we aren't using it. Like Hawaii.

One of the key things that we need to deal with is the continuity of supply. There are some situations (hospitals, air traffic control, etc) where we must have reliable power 60/60/24/7/365. That means really huge batteries or some options for when the wind don't blow and the sun don't shine. Certainly not insurmountable, but we must think.

We also need to understand that until we get breeder reactors and other Star Trek advances that we will need fossil fuels. And we will have to make choices. You want to burn that gas in your boat chasing salmon on the Big Blue or save that petroleum for the (say) Navy and Zoomies.