By Laura McDaniel
Environmental Public Affairs

PATUXENT RIVER NAVAL AIR STATION, MD—Last month, NAVAIR Patuxent River engineers flipped a switch to turn on a gizmo called a PEM fuel cell – the first in the Navy – that many people are hoping will be the 21st century solution to a host of so-far-unsolved 19th and 20th century energy problems. The engineers then flipped another switch and put a second PEM fuel cell online.

The fuel cells are installed at the Natural Resources office and at a station residence, and are the first fuel cells of this type in the Navy to launch.

A fuel cell is a hybrid device, about halfway between a dynamo or generator, which produces electricity, and a battery, which stores it. (PEM stands for proton exchange membrane; see the sidebar, “What is a fuel cell?” below).

The PEM fuel cell installation is a joint project between NAVAIR Pax River and the local electric utility company, Southern Maryland Electric Cooperative. In fact, it was SMECO that initiated the project when it received a grant in May 2001. In order to put the grant into practice, SMECO knew where to turn for help: NAVAIR Pax River.

“There’s a reason Pax River was the first to do this,” said Mike Oliver, Public Works engineer and the Navy point-of-contact for the project. “We had our site prep work all ready ahead of time, all the underground wiring, electrical, and the co-generated [use of heat by-product] designs. Having that all done on our end was a big help to SMECO.”

Fuel cells are a type of environmentally friendly power system. Most types of fuel cells work by extracting hydrogen from hydrocarbon fuels, then combine that hydrogen with oxygen to create water molecules, producing electricity as part of the sub-atomic process.

Fuel cells also produce heat as a “waste by-product.” With planning, this heat can be used for other useful purposes, such as heating a residence; this is called “co-generation.” The PEM fuel cells here operate at about 155 degrees Fahrenheit, much cooler than many other kinds of fuel cells.

Two different types of PEM fuel cells have been installed here. The fuel cell at the Environmental Office is using propane as its energy source. The system is set up to use both its electricity and heat byproduct to heat the building, cutting down on the cost of fuel. The residence, known as Quarters Y, is using natural gas. In this building, the fuel cells are creating electricity for residential use and heating water for the building.

The fuel cells were manufactured by H Power Inc., of Belleville, N.J. (On Nov. 12, H Power announced it was being acquired by and merged into a company called Plug Power Fuel Cell Systems, of Latham, N.Y.) The PEM fuel cells were installed and will be maintained by SMECO and Public Works utilities for a testing period of 12 months.

In May 2001, SMECO was awarded the grant from the Army Corps of Engineers to study fuel cells and then approached the Navy to see if Pax was interested in hosting a fuel cell project. Pax was excited to be part of the trial of energy efficient products.

Mike Rubala, energy services supervisor for SMECO, helped lead the project. “Mike Oliver and I looked around [on station] to find the best test sites,” Rubala said. “We picked these for the different uses they would have.”

He said the Army Corps of Engineers was looking for a variety of sites that would have different geographical qualities, environmental stresses and fuel uses.

“These units [at Pax River] are at sea level and are subject to saltwater spray,” said Rubala. “They’ll show temperature fluctuation and high humidity, and we’ll be testing at both a housing [Quarters Y] and a small commercial unit [the Environmental Office].”

Capt. Charles Miller, Public Works officer, is affected by the project in more ways than one: he’s also the resident of Quarters Y.

“The proton exchange membrane fuel cell demonstration project provides a unique opportunity for the Navy and SMECO to learn about this new technology,” Miller said.

“The project, funded under a grant from the U.S. Army Construction Engineering Research Laboratory, will help promote the installation of environmentally friendly power systems. The project not only promotes environmental and energy conservation but also energy security by furthering the application of field-reliable, off-grid electric systems. Thanks to Public Works Utilities, SMECO and the manufacturer, H Power, Inc. for their valuable support during the construction phase of the fuel cell demonstration project.”

“I’m excited by the potential for an environmentally friendly power generation source,” said Kyle Rambo, Conservation Division lead. “The really neat potential with this is for use in remote areas where we wouldn’t have to clear miles of forest for transmission lines.”

“Fuel cells are not 100 percent reliable yet, so we still have a backup system, but we’ll get there,” said Rubala. “The technology is progressing every single day. There are a lot of smart people working on this worldwide.”

Sidebar:

What is a fuel cell?

Ever since Ben Franklin flew his famous kite during that thunderstorm, and Alessandro Volta invented the battery, scientists and engineers have been laboring day and night to figure out the cheapest, most efficient and most environmentally friendly way to generate electricity, transport it or store it, and otherwise have it on hand when needed.

It hasn’t been easy. Unlike virtually every other scientific endeavor since the Industrial Revolution, making and storing electricity has stubbornly resisted all but the smallest improvements. For the next 200 hundred years after Franklin and Volta’s work, the creation and use of nuclear power was the only major “high-tech” advancement over garden-variety batteries, hydroelectric dams built by Mother Nature and cement, and coal-burning or oil-burning power plants. And it soon became apparent that nuclear power was no cure-all.

Fuel cells were born and developed during the Space Race of the 1960s, when it became absolutely crucial to develop some new method to produce electricity in outer space, since all existing methods and storage devices had fatal defects: size, weight, combustion byproducts. In fact, combustion itself was not an option in space, since it requires both the storage of a fuel, and the oxygen to burn it. There’s no wind or water in space, so windmills and hydroelectric aren’t options. Solar power doesn’t work at night – or on the dark side of the moon.

Instead of using combustion to spin electric dynamos, fuel cells use chemical reactions to produce a flow of electricity, so a fuel cell is a device similar to a dynamo or generator, but with few if any moving parts. It is also something like a battery in that it has positive and negative terminals (electrodes) as well as an electrolyte (in this case a solid one made of plastic, instead of a liquid like battery acid).

Over the years several dozen types of fuel cells have been invented and put into limited practice, most with serious trade-offs or problems. In general, most are considered to be more environmentally friendly than combustion-based systems because they usually produce only heat and water as byproducts. But ecology isn’t the only consideration; initial cost, cost-effectiveness, output, and operational issues come into play. There’s a fuel cell that works just fine – but it runs on molten sodium, and it won’t make a very good flashlight or electric automobile power source. All are horribly expensive, and many operate only at temperatures above a thousand degrees.

The two PEM fuel cells now operational at Pax River may solve most or all of those problems. PEM stands for proton exchange membrane. It uses commonly available gases like propane or natural gas as the fuel source, but it doesn’t burn them. Rather, it uses a catalyst (in this case, a thin coating of platinum on one surface of the plastic membrane) to break down the hydrogen in the propane into its atomic parts. When hydrogen is fed to the anode side of the cell, the catalyst makes the hydrogen atom break up into two electrons and two hydrogen ions (protons). The resulting flow of electrons is an electric current, which can be harnessed while the protons migrate through the membrane. Once these parts have crossed through the membrane (the electrolyte), the electrons and protons re-assemble back into a hydrogen atom; a pair of these atoms simultaneously react with an oxygen atom to produce water, finishing all the chemical and atomic processes, and silently generating only some heat, water and electricity as a result.

Typically, PEM fuel cells operate at a reasonably low temperature of about 150 to 200 degrees Fahrenheit, and produce power in the range of 50 to 250 kilowatts, which is considered to be an excellent “power density.” Power output can be varied quickly, making PEM fuel cells very suitable for things like automobile power cells and power systems for buildings. With no moving parts and no liquids, corrosion and maintenance are vastly reduced.

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