I’m serving on a small working group that is trying to develop some high-level ideas for how the City of Portland could encourage more sustainable freight.
It’s a little bit of a mind-bender, because all of my urban design sensibilities push for smaller vehicles.
But in fact from a fuel efficiency perspective, there is a very strong inducement toward larger trucks and keeping them full. Fuel per pound of cargo goes down as trucks get bigger (regardless of what vehicle technology improvements you make like electric or biodiesel).
The other half of the question is reducing vehicle miles traveled (VMT). Obviously from this point of view it’s better to send out a full truck and let it deliver until it’s empty.
The problem is, many customers want their deliveries at the same time (7-10am is typical). This can result in running many partially empty trucks at the same time, because you can only fill the truck with what it can deliver during that window.
Some of the keys to making this more efficient would include:
- Getting customers (with some kind of financial inducement?) to accept night-time deliveries or deliveries over a wider time span during the day
- Getting customers to hold more inventory so they get larger, less frequent deliveries (doesn’t work for perishable goods)
It’s a very interesting set of tradeoffs.