Today, the Urbanophile tweeted a link to a "caution" about bike share from Payton Chung. While I agree that caution is in order, I'm disturbed by the framing of Chung's piece, particularly the assumption that a significant amount of "rebalancing" is necessary in any bike share system. Rebalancing is where share bikes are transported, usually in a truck, from "full" stations to "underutilized" ones. Let me go through my ideas in response to that:
First, there's something profoundly depressing about a bike system supported by large gasoline-powered vehicles. I first got the same feeling when I read about the large long-distance bike rides - not tours - that are supported by "sag wagons." Essentially, you ride your bike, but you're paying for someone to drive ahead of you with your stuff. This happens in races, too. A single sag wagon can carry stuff for multiple cyclists, but it still undercuts the whole idea of bicycles as transportation.
Paris's Vélib´system, as the first large-scale bike sharing system, showed that there is an imbalance in the use of the bikes - or at least two, in fact. First, there's a daily pattern where people ride their bikes from home to work and back again. Most bike share stations are not equally balanced in terms of home and work destinations, so the ones that have more homes nearby tend to be emptier in the middle of the day and fuller at night, and vice versa for stations close to jobs. There were similar patterns in terms of travel to shopping, recreation and metro stations.
This one seems like a no-brainer. The system should simply be built with enough flexibility to absorb extra bikes depending on time of day. There should be enough bikes at the home stations in the morning, and at the work stations in the afternoon. This may seem like a waste, but it's preferable to driving the bikes back to the home site for another wave of commuters, and back in the afternoon.
Secondly, the Vélib' managers found that people were quite willing to ride their bikes downhill, and less so uphill. Brian McEntee tweeted that Paris and DC have experimented with building incentives into the pricing structure to encourage people to ride uphill. This seems like a promising response.
It seems to me that there are two primary goals for a bike share system. One is to encourage cycling at the expense of any other mode, thus turning everyone into part-time cyclists and building a constituency of cyclists who will then support other parts of the agenda. The other is to create a composite transportation system that is more flexible, convenient and efficient than private cars. If you really want to increase efficiency overall, you need to look at how much fuel consumption, pollution and carnage a "rebalancing" trip adds to each bike ride.
Does the rebalancing (and all the other fossil fuel use that goes into a bike share system) make it more efficient, cleaner or safer to drive a single-occupant vehicle? What about a bus? Bike share works best with trips that are too dispersed to warrant a transit route, but if you're paying someone to drive a diesel vehicle back and forth, you might as well skip the bike share and just run a bus.