Fuel Cells 101 - Ohio Fuel Cell Coalition

Fuel Cells 101
What are fuel cells?
Fuel cells are an advanced energy technology that uses a chemical reaction to harness hydrogen and
oxygen to generate electricity without combustion or harmful emissions. The only byproducts are pure
water and useful heat.
What makes fuel cells different from other energy sources?
A fuel cell running on pure hydrogen is a zero-emission, high-efficiency power source. Some fuel cells
use natural gas or hydrocarbons as a hydrogen “feedstock,” but even those produce far less emissions than
conventional power plants. Fuel cells are also very quiet, reducing noise pollution. Fuel cell vehicles
operating on hydrogen produce zero pollution. The only byproducts are water and heat. Even if
hydrogen is produced using fossil fuels, fuel cell vehicles can reduce emissions of carbon dioxide by over
50% and use less than half the fossil fuel input.
Why fuel cells?
Fuel cells have several advantages over other technologies for power generation. They emit no pollutants
and use far less input fuel. Fuel cells offer unique characteristics that provide unprecedented advantages,
such as “off-the-grid” power supply, dependability and quiet operation.
What kind of fuel cells are there?
There are a variety of fuel cell types, which are often categorized by the electrolyte they contain. The
best-known types are alkaline, molten carbonate, phosphoric acid, proton exchange membrane and solid
oxide. Direct methanol and regenerative fuel cells are also being extensively developed.
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How do fuel cells work?
Fuel cells generate electricity
from an electrochemical
reaction in which oxygen
(air) and a fuel (e.g.,
hydrogen) combine to form
water. The different kinds of
fuel cells share the same
basic mechanism. Hydrogen
fuel is fed into the anode of
the fuel cell. Oxygen (or air)
enters the fuel cell through
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the cathode. A catalyst
serves to split the hydrogen atom into a proton and electrons, which take different paths toward the
cathode. The proton passes directly through the electrolyte. The electrons, which cannot pass through the
electrolyte, go around it, forming a separate current that can be utilized as a power source, before they
reach the cathode, where they are reunited with their protons and oxygen to become water. Unlike
internal combustion, there are no emissions from this process and the only byproducts are water and heat.
The electricity produced can be used to power all sorts of devices, from cars and buses to laptops and
mobile phones. In some applications, the heat byproduct is also used to heat residential dwellings.
When was the fuel cell invented?
Fuel cells were initially demonstrated in 1839, by Sir William Grove, often called the “Father of the Fuel
Cell.” Francis Bacon developed the first fuel cell device in 1932, with a hydrogen-oxygen cell, but he
was challenged by several technical hurdles. It wasn’t until 1959 that Bacon demonstrated a practical
five-kilowatt fuel cell system. Around the same time, NASA began to develop fuel cell technology for
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the space program. Fuel cells soon became an integral part of NASA’s energy portfolio, supplying
electricity to several space missions.
However, it wasn’t until the 1990s that fuel cell technology reached significantly into the private sector,
with a broad range of commercial applications in production or research and development.