I'm doing business (in my household) with both Tesla and Solar City. I can tell you this about Solar City: They're doing with roofing and power meters what Tesla is doing with vehicles. They're promoting a location-aware distributed electric-distribution grid.

We're lucky right now that the government's promotion of PV is putting the burden of power storage on the power-grid operators. Without net metering, this stage of PV would never happen. But net metering is essentially bad for the grid operators; they get paid nothing for storing power or sending it from a net producer to a net consumer. They will eventually prevail like they tried to do in Nevada earlier this year and buy power cheaper than they sell it.

But in the meantime the power grid companies haven't got a chance without competition. My home electric meter is as dumb as a box of hammers, even though I spend a lot of money with it and rely on it to keep my family safe in the winter. If that meter were capable of telling me when the power I used was coming from a peak-load diesel generator, I would happily turn off my electric stuff. But they can't do that now.

PV needs to use this window of opportunity to get going, and to get other power-storage solutions working. A Model S is one of those solutions: a gigantic battery with wheels and cruise control. To my way of thinking, systemwide integration is an electropolitical move worth making.

From a personal point of view, I can say that Solar City's sales and engineering teams are smarter and more committed than the people at other PV companies I spoke to. They are trying to build a scalable business rather than bopping from town to town installing stuff and moving on.

Will this work long term? Who knows? But it's worth trying.