I don't really get the constant focus of the energy conversation on transportation (< 1/3 of total energy use). If, as you say, we can get solar energy to the g

I don't really get the constant focus of the energy conversation on transportation (< 1/3 of total energy use). If, as you say, we can get solar energy to the grid for less than coal then we're getting close to the time when no one will ever build a coal plant again. Then accelerating economies of scale will cause the price to fall to the point where we're shutting down fossil fuel plants, then to the point where we can make biofuels with solar rather than fossil fuels. Now GHG emissions are down 75-90% with a set of mostly evolutionary technical advancements. Some environmentalists might not like that process because it's market-driven and doesn't involve any economy-shrinking monastic self-sacrifice (e.g. Kyoto protocol), but it is the reason I'm reasonably optimistic about climate change.