I don't think UPS has to make a decision between reducing operating costs or delivering more packages. The company says this particular truck is best suited to urban use, where its narrower size makes it easier to get around--and therefore speeding deliveries. As the article states, the 900 lbs difference is in the truck's weight, not the weight of its contents, and the contents difference is measured in cubic feet: it's about 70 cubic feet smaller.
So now on to the difficult decision: Reduce operating costs or deliver 900 lbs more packages without raising the current cost. Ether way, it is a huge win. Hooray for enterprise for innovating new cost savings in transportation. All we got from government was a PSA about correct tire inflation.
It appears that UPS is in good company with their decision to explore the use of composite materials. I've read about several other pilot projects in the mass transit and delivery sector where they are out in front leveraging both new materials and alternative energy vehicles to try to cut operating costs. Given that the trucks are the fuel constitute huge operating costs, the strategy makes a whole lot of sense.
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