But that led me to wonder: how sure am I about the relative merits about the electric vs. gas? I mean, yes, there are oft-cited statistics like "120 MPG equivalent" when you plug the car in -- but surely that's a gross oversimplification. From an *environmental* perspective (I'm not talking about cost here), there are lots of confounding factors that have to be taken into account. For example, what is my electricity mainly based on? Wind vs. coal makes a dramatic difference in the environmental impact of my electricity, and finding out the actual percentages isn't simple. (Yes, I can tell the power company "I want green electricity", but that really is just influencing the mix, rather than giving me entirely greener-based power.)
Moreover, there's another oft-cited statistic, that half of all electricity is lost in transmission. I *assume* that the amount of loss is proportional to where I am, though -- that there's a big difference if I'm 1000 yards from the power plant, as opposed to ten miles away. (Physics types should please tell me if that assumption is incorrect.) But I haven't the slightest clue how long the wires are between me and the nearest power plant, much less how the other plants in the grid factor into that. Figuring out how much electricity is being lost getting to *me* is quite difficult even to approximate realistically, and I would expect that to make a significant difference in the actual environmental footprint of this theoretical plug-in car.
So I find myself wishing for a website that would allow me to give the location of my house, and which would produce a *realistic* estimate of what my electricity looks like environmentally. I have no idea what the business case for such a website would be (and heaven knows, I don't expect it to be simple to write), but with awareness of environmental issues on the rise it seems like it ought to have a market. If Google wants a next project for their "organize all the information in the world" push, that might be a worthwhile thing for them to tackle...
