After noting recently that there was movement again in the portable fuel cell market, a reader dryly noted that we'd been down that road before and come to a dead end. More like an uneventful drive with no scenery and nothing but rest stops, I'd say. Regardless, there is a parallel road that isn't examined quite as often in the press: stationary fuel cells.The big boxes, often fired by natural gas, combine cooling, heat, and power to make data centers more energy-efficient. They fall into the category of greener computing. They still use fossil fuel, but far more efficiently than pulling electricity from coal-burning power plants.

In case you haven't seen any of these creatures, the fuel cell industry is gathering en masse in Phoenix next week to show off its wares and compare notes at the 2008 Fuel Cell Seminar & Exposition.

Among those exhibiting is UTC Power, a subsidiary of United Technologies, whose fuel cells and power plants are relatively common in the nascent market, as evidenced in California, where they are deployed in a variety of large enterprises.

As for portable fuel cells, you'll hear them discussed but probably see little evidence of them at the Phoenix show. And that's reflective of the commercial market, says Valerie Browning, technical program chair of the Fuel Cell Seminar. "I do think fuel cells have made progress. We're starting to see them in applications," she says. Rather, the market for fuel-cell chargers for 20- or 100-watt portable electronics is a more likely market in the near term, particularly in areas where the grid isn't available or reliable, says Brown. "But some of these applications that receive a lot of attention -- for example, fuel cells with cell phones and computers -- don't make the most sense."

There are some who are a little more sanguine on the portable fuel-cell market. Among them, Viaspace subsidiary Direct Methanol Fuel Cell Corp. (DMFCC), which in July signed a manufacturing agreement with Tyco Electronics. DMFCC will be at the show next week, as well.