I'm still chewing on the transportation efficiency thing. This isn't necessarily productive, as it's easy to go crazy trying to figure this stuff out in the abstract. (It's also easy to get things badly wrong, like an early report that electric cars would emit 60x as much lead per mile as a conventional car burning leaded gasoline. Even were the numbers valid, are all "emissions" equal? Lead particles in the air, ready to rain down into the drinking water, seems different from the occasional fully encapsulated battery ending up in a well-maintained modern landfill.) It's also unnecessary from a policy perspective. You don't need to best answer to set policy, just a way to price the positive and negative externalities, so that those costs can get included in the prices paid by consumers. Let the invisble hand work out the optimal compromises.

Still, even if I want to do the calculation, I'm not sure how to do it. There are so many large uncertainties. Does it really make sense to charge the bicyclist for food energy? After all, perhaps they would normally have driven their SUV to the gym to work out for an hour a day had they not been biking, making their personal energy expenditure neutral. Do increases in exercise, at the margin, always lead to increased food consumption? In increased food purchasing? Human physiology is more complicated than mechanical engines, and it's easy to imagine physiological states where increased exercise leads to decreased consumption. Does increased food purchasing lead to increases in production, or simply less waste as farmers produce all they can in any case? Are we interested in energy costs at the margin, under current conditions, or in some ideal Kantian centrally-planned state where everyone is making the same choice? You've got to answer all of these before generating an answer. Still, I bet the Lomborgians would love any calculation (no matter how valid) that showed bicycling to have a bigger environmental footprint than driving an SUV.

ObRide: Through rationing power usage to be kind to the battery, I made it all the way to work yesterday, and home again too. 25.3 final there, 25.5 final back. I felt like I was outpedalling the motor during the hard parts, though, resulting in no assist. Just can't win.