>I don't agree. Doing everything in your own back garden is extremely inefficient.

What you say is true in principle. But you say "allowing for the cost of transport" as though this cost were trivial, when it is actually enormous.

What's the best location for wind power? You should turn North Dakota into one big wind farm. Since the local demand is basically zero (compared to CA), you ought to build a transmission line to take the power to where it's needed.

Setting aside the losses from long distance transmission (which are not trivial, but let's keep it simple), what's involved in building a transmission line from North Dakota to California? You have to get zoning permits and purchase right of ways over hundreds of miles. Some people will refuse to sell you the land, so you have to take them to court and take the land by eminent domain. People hate the way high voltage lines look, so they are going to fight having them built nearby. It's a political and social nightmare, as well as being expensive in materials and labor. And assuming you plan to get paid for your transmission line, by the time the power gets to California, it's going to cost 3-4 times what power generated from fossil fuel costs. Like it or not, people aren't going to want to quadruple their power bills just to "go green".