Hydrogen knowledge lybrary
General H2 technology
What is a Fuel Cell ?
Basically fuel cell in common language, is a device which converts chemical energy from a fuel into electrical energy which happens by undergoing a chemical reaction where positively charged hydrogen ions reacts with oxygen or any other oxidizing agent.
What kind of Fuel Cells are being used?
Fuel Cells are devided on the basis of used kind of electrolyte. Most common are these:
How does most common PEM Fuel Cell work?
Advantages of PEM are especially - high power density and relatively low operating temperature (ranging from 60 to 80 degrees Celsius.
How does a fuel cell differ from a battery?
A fuel cell is different from a battery cell in that reactants are constantly supplied to a fuel cell making it an open system whereas a battery cell is a closed system that stores the reactants within it. A fuel cell works as long as fuel is supplied to it whereas a battery cell requires regular replacements.
What are the benefits of using a fuel cell?
Why use a fuel cell?
Fuel cells offer a variety of benefits compared to traditional power generators. They are generally more fuel-efficient, operate with very little noise and produce no harmful emissions at point of use (fuel cells which use renewable hydrogen as fuel produce only water). They have no moving parts and are thus easy to maintain. In addition to electrical power, they produce high-quality heat which can be used for heating (or to drive refrigeration cycles for cooling), so improving the overall efficiency of fuel use.
What can fuel cells power?
In principle, fuel cells could power anything that requires electrical energy to function. This could range from a mobile phone up to a city. Current commercial applications include off-grid power for telecoms stations; back-up power for buildings; drives for forklift trucks; residential heat and power; and portable generators and recharging devices.
Why not burn hydrogen instead of using it in a fuel cell?
Hydrogen is an extremely clean-burning fuel, and offers a good alternative to gasoline or diesel for internal combustion engines. However it is also good alternative to Natural gas heating. New HCHP (Hydrogen Combined Heat and Power) are already on a market where integrated Fuel Cell producess electricita and low grade heat (<80°C) and H2boiler supply heat when Fuel Cel thermal capacity is over limit. For comparison hete is a table of CO2 emmisions produced per 293 kWh
Fuel cell types
How is the hydrogen produced?
Although there are huge quantities of hydrogen in the universe, very little of it here on Earth is in a freely-available form - it is usually present in a compound with other elements , most achievable is water. Most industrial hydrogen is currently produced from oil or gas, by reforming of the hydrocarbon feedstock to produce synthesis gas (syngas), primarily a mixture of hydrogen and carbon monoxide. However this is not CO2 free technology and therefore we mainly focuss on electrolysis which aloves to produce hydrogen with zero carbon emissions. This can be done by using renewable energy (particularly solar, and wind) to power an electrolyser to split water into hydrogen and oxygen. The hydrogen is then compressed, stored and transported from the site of production to the point of use. Running a fuel cell on this hydrogen produces zero carbon emissions.