Feb 1, 2010 12:00 PM, By Donny Jackson (donald.jackson@penton.com)

Fuel-cell and renewable-energy advances are providing more options for powering remote sites

Despite all of the advances in wireless technology — which have sparked blurry-fast evolutions of feature sets and devices, and spawned an alphabet-soup of acronyms for the latest protocols — power availability remains a simple, yet critical, factor.

With power, even the most arcane wireless systems can provide valuable, powerful communications across vast distances. Without power, the latest and greatest wireless infrastructure is nothing more than an expensive eyesore, and the niftiest devices transform into costly paperweights.

This fundamental reality often impacts the location of base-station sites. What an engineering map may identify as an ideal site — in terms of providing RF coverage in a remote area — may not be viable because the electrical power grid does not reach the location, and trying to extend commercial power to the prospective site would be cost-prohibitive.

For commercial wireless carriers, the good news is that consumers typically want to use their cell phones in areas where the power grid is readily accessible. But the first-response community does not always have that luxury, because emergencies often occur in areas where no power company could justify the cost of providing service.

“There are some interesting factors involved — whose land you're going over, whether the utility can be run overhead or underground,” said Jim Parcels, director of systems management for the Pennsylvania statewide radio system.

“Often, in state forest land and particularly state parks, they are loathe to allow overhead lines to be run,” he continued. “And, of course, the cost of running electricity underground is dramatically more expensive than running it overhead.”

Internal combustion-based generators are a traditional choice, but the need to refuel and maintain them in certain locations — particularly in mountainous areas — make them impractical, because the site may not be accessible for months in the winter.

In the past, such a scenario would require the state to pay the utility more than a hundred thousand dollars to extend electricity to a site or compromise its coverage in the area. But this spring, Pennsylvania plans to build a microcell site in Clinton County using renewable energy sources — solar and wind energy — and hydrogen fuel cells to power the site, in the process avoiding the capital costs associated with extending the power grid.

The notion of using alternative power sources for a communications site is not new. Less-developed parts of the world have harnessed alternative-energy sources out of necessity, because they lack a power grid in many locations. But the alternative-energy option typically has been deemed too expensive to be used regularly in the United States, where electrical service is almost ubiquitous.

Indeed, Pennsylvania seriously considered deploying fuel-cell solutions for some remote, high-profile tower sites for its statewide radio system eight years ago. The notion was dismissed at the time largely because the capital and operational costs associated with the solution were too expensive.

“In those days, when we looked at doing it, you were talking about a big trailer with a tank on it [to deliver hydrogen to the fuel cell at the tower site], so access was an issue and cost was an issue,” Parcels said. “It was just overwhelming.”

There also was a technical problem at the time, said John Struhar, Harris' director of Pennsylvania operations.

“They had problems because the discharge from a fuel cell is water,” Struhar said. “These things would freeze up because they were on mountaintops in the cold and the wind.”

Today, the alternative-energy option is more practical for several reasons. Heating elements have been integrated into the fuel-cell solutions, so freezing no longer is a problem, Struhar said. And Pennsylvania now is trying to power only single-channel microcell sites, which require about a tenth of the power of a full-fledged tower site that supports multiple channels and trunking features, Parcels said.

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