Power to the People

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Going off-grid is about to get a whole lot easier. A handful of companies across the nation and around the globe are racing to bring to market dishwasher-sized appliances capable of meeting all of a home's electrical needs. Remarkably reliable, cost-competitive, energy efficient, environmentally friendly, virtually noiseless and as easy to install as a new furnace, these units will change forever the way we think about—and generate—power.

This is no pipe dream, nor is it some futuristic technology still light-years away. In fact, the science behind these new wonder units is more than 150 years old and fairly basic (see "Back to the Future," ). We're talking here about fuel cells, devices that make electricity from hydrogen and oxygen, emitting as byproducts pure water and heat. Fuel cells have for years been on the minds and drawing boards of big-name automakers seeking to produce a near zero-emissions passenger car. But the technology remains too bulky and expensive for widespread automotive use.

Which is why, though a latecomer to the fuel cell field, stationary power systems will be first to go commercial, as soon as January 2001. And while the initial units will likely sell for $7,500 or more, that price is expected to quickly tumble below $4,000 as manufacturers move into mass production.

"There are no fundamental technology breakthroughs [still] required to make this product; they've all been done." says Dr. William P. Acker, vice president of product development and commercialization for the Latham, New York-based Plug Power, a leading developer of fuel cells. "Now it's just good, roll-up-your-sleeves engineering, designing, building, testing and product development."

Fuel Cells 101

Like batteries, fuel cells create electricity through a rather simple electrochemical process. Generally, a fuel cell consists of a positive electrode (cathode), a negative electrode (anode) and an electrolyte that conducts ions between the two. There are at least five kinds of fuel cells under investigation for various applications, each using a different electrolyte, but the type garnering the most attention for residential use is called Proton-Exchange Membrane (PEM).

A PEM fuel cell employs as its electrolyte a polymeric membrane—it looks, says Acker, much like a piece of Saran Wrap—coated with a catalyst. Hydrogen is introduced at the anode, then passes to the membrane, where the catalyst splits the hydrogen molecules into protons and electrons. The protons then pass through the membrane to the cathode, where they react with oxygen to form water and heat. The electrons, unable to pass through the membrane, are forced to travel around it, creating DC electricity in the process. The fuel cell systems being developed by Plug Power and others will come equipped with a conditioner to turn this DC current into usable AC power.

Fuel cells can be stacked—think of a club sandwich—to meet loads ranging from 1to 50 kilowatts (kW) or more. And unlike batteries, which generally have to be recharged or eventually replaced, fuel cells will continue to generate electricity so long as there is a supply of hydrogen and oxygen. Acker predicts his company's fuel cell systems will see useful life spans of 15 to 20 years, or about what you'd expect to get from a typical home furnace.