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buildings, an approach known as cogeneration. ONSI’s marketing manager, Gregory J.

Sandelli, states that in 1.25 million hours of total use, his company’s cells have remained in

operation 95 percent of the time–a figure that bests on-site, diesel-powered generators.

The units, which use phosphoric acid as an electrolyte, are designed to last twenty years

(Scientific American).

Phosphoric acid-based cells tend to be heavy, which makes them less ideal for use

in vehicles. Other companies are developing cells that are specifically designed for that

purpose. Ballard Power Systems in Vancouver, BC, has for several years been developing

a lightweight fuel cell, the “proton-exchange membrane” (PEM) type. In place of

phosphoric acid, PEM cells employ a thin polymer membrane as their electrolyte. By mid-

1997, Ballard planned to launch a pilot fleets of a fuel cell-powered passenger buses in

Vancouver and Chicago. The U.S. Department of Transportation is also developing fuel

cell buses.

When portability is not an issue, as it is not for municipal utilities, other

possibilities open up. “Molten carbonate” and “solid oxide” fuel cell technologies, for

instance, could bring extraordinary efficiencies to power-generating stations. These

devices run at far higher temperatures than PEM or phosphoric acid cells. Molten

carbonate and solid oxide cells might be able to achieve an impressive efficiencies of 55

percent or more, according to Robert R. Rose of Fuel Cells 2000, an advocacy group.

The hot steam and carbon dioxide they produce can be used to drive a gas turbine that

generates additional electricity, an approach that could push their efficiency to an unheard-

of 80 percent. They are potentially up to twice as efficient as a typical oil or coal-fired

plant (Scientific American).

Energy Research Corporation (ERC) in Danbury, Conn., has built a two-megawatt

pilot molten carbonate plant for the municipality of Santa Clara, Calif. The fuel cells run at

about 650 degrees Celsius (1,200 Fahrenheit) and consume hydrocarbon fuel that is re-

formed into hydrogen right inside the cells. Problems with electrical shorts within the cells

have restricted the plant’s output so far to about one megawatt. As the ERC’s William V.

Baker is at pains to point out, however, that still makes the Santa Clara plant the highest-

powered fuel cell unit in the U.S. The company is currently developing a modified design

rated at 2.85 megawatts (Scientific America).

Future.

Although no one can tell the future of fuel cells, you can tell what direction they

are headed. DaimlerChrysler plans to market their fuel cell cars by the year 2004.

Engineers plan to take off 660 pounds of the engine weight before marketing to the public.

Ford says they will unveil a fuel cell car this spring. Other automakers such as General

Motors Corp. and Honda Motor Co. are pouring in hundreds of millions of dollars into the

fuel cell car industry. (Associated Press) Companies are developing solid-oxide fuel cells.

DaimlerChrysler officials are working on NECAR X, which will run on methanol.

Methanol contains hydrogen and is the auto industry’s favored fuel to power fuel cells.

However, methanol-fueled cars would require a national network of methanol stations.

To understand fuel cells you need to know how they work, how they are being

used today, and how they will be used in the future.

Section II.

When evaluating an energy source two good criteria to use are environmental

friendliness and reliability.

Environmental friendliness is a good piece of criterion to use when evaluating an

energy source. Environmental friendliness is how much the resource affects the

environment. Environmental impact is very important because if you don’t respect the

earth now you won’t have any resources later. Without natural resources we won’t be able

to live. If we keep letting carbon dioxide go into the atmosphere and kill trees and other

plants we will die of carbon dioxide poison. We will also continue global warming.

Electricity is a good example of environmental friendliness because it doesn’t have any

harmful waste products.

Reliability is a good criterion to use when evaluating an energy source. Reliability

is how well you can depend or trust something. Reliability is very important because it is

often in crisis or when we need something the most that it is unavailable or doesn’t work.

In an emergency situation reliability is very important because it can save lives. When

your power goes out you want a reliable flashlight, or when your driving down a deserted

highway you want reliable tires so you don’t get a flat. Therefore reliability is a very

important criterion to use when analyzing an energy source. Solar power is reliable

because the sun comes up every day. It is a fact that sun will come up everyday.

These two criteria are very important when evaluating an energy source.

Section III.

In this section you will be told how the criteria apply to the energy source. Fuel

cells are a good energy source because they are environmentally friendly and very reliable

despite being expensive.

Fuel cells are environmentally friendly because their waste product is a little heat

and water vapor. This shows environmental friendliness because they do not pollute the

earth. By

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