Letters to the Editor

the ancient art of military logistics
Re: "mission possible," June 2009
Great article about the transition efforts under way in Iraq. DC VELOCITY has done an excellent job updating readers on the efforts of our military forces around the world. Since "logistics" was born out of ancient military campaigns, it is only natural that the magazine continue to feature these types of articles. I also enjoyed the fact that the logistician was a female.
Scott McWilliams, OHL

well, duh!
Re: "the fatal flaw in ERP," TechWatch, March 2009
Of course this solution [Mark Payne's formula for calculating how much a company must produce to meet demand] is right. Inventory is what is supposed to be variable along with demand. In the short term, production (supply) cannot be variable.
Andrew DeWitt, Tosca Ltd.

talkin' about (energy) generation
Re: "cell-ing the transition," June 2009
Mark B. Solomon's otherwise excellent article on hydrogen fuel cells for lift trucks included an estimate by a battery-charger developer that a fuel cell-powered lift truck uses three times more energy than a truck using a battery. This statement is meaningless without specifying both how the hydrogen is produced and how the electricity used to charge batteries is being generated.

According to an Argonne National Laboratory study published in 2008 (Full Fuel-Cycle Comparison of Forklift Propulsion Systems), a fuel cell forklift using hydrogen produced on site from natural gas—a technology that is commercially available from Nuvera and others—uses less energy than a battery-powered forklift when recharged with standard U.S. grid electricity, on a national average basis.

The Argonne National Laboratory report is available, at no cost, through the Department of Energy's Office of Scientific & Technical Information's Web site.
Gus Block, Nuvera Fuel Cells