Many fuel cells convert the energy from hydrogen into electricity. Although hydrogen has many industrial usages, not everybody is yet familiar with hydrogen as a fuel. Please find below answers to frequently asked questions.
What is the role of hydrogen in fuel cells?
PEM fuel cells need hydrogen to operate. Hydrogen is the most common element in the universe. Hydrogen is an excellent fuel for many reasons. First of all, hydrogen has the highest energy content of all fuels: about two and a half times as much energy as natural gas or petrol per mass unit. Furthermore, hydrogen is exceptionally clean (non-toxic, odourless and carbon-free). It can be produced from many resources. It is safe to produce, store and transport, even in large amounts. Hydrogen is expected to play an important role in decreasing our dependency on fossil fuels.
Hydrogen provides sustainable and flexible energy solutions if zero-emission targets have to be met, efficiency has to be improved or if you simply want to contribute to a cleaner ecosystem. Nedstack offers safe and sustainable answers to your energy needs with state-of-the-art hydrogen fuel cell technology at a competitive price.
Where does hydrogen come from?
Hydrogen, the universe’s most common element, does not occur in a naturally free state. It is bonded to other elements. For this energy carrier to be used as a fuel, it has to be produced. This can be done in many ways. The most commonly used method is reforming hydrocarbons, like natural gas, propane, methanol butane or propane. It can be produced from sustainable sources of methane such as biomass or land-fill gas. It can also be obtained by electrolysis, breaking apart water, or it can be extracted from carbon-free compounds, such as ammonia or boron compounds. Renewable energy sources, like wind, solar, geothermal and hydroelectric power, can all be used to produce hydrogen.
Hydrogen can be produced in dedicated plants and transported, or it can be produced in small point-of-use units. In production processes which generate hydrogen as a by-product, fuel cell technology is used to generate electricity and heat.
How much hydrogen is consumed by a fuel cell?
The amount of hydrogen a fuel cell consumes varies depending on a number of factors. The most important are the voltage at which the fuel cell is operated and the parasitic loss of the balance of plant components. The stack design and characteristics can have a large influence on the latter. If you have questions about the amount of hydrogen or the size of fuel tank needed for a specific application in your industry, Nedstack will be able to help you with the relevant calculations.
Is hydrogen safe?
Hydrogen has very high energy content on a mass base and reacts easily with air. These properties make it an attractive fuel. At the same time, like other fuels, care should be taken to limit the risks accompanying the use of hydrogen. The hydrogen industry can be characterized as risk conscious, and has learned how hydrogen risks can be safely managed. One cannot state that hydrogen is safer or less safe than other fuels as it has quite different properties than other fuels. Because of this risk consciousness, comparably little injuries and damages are related to the release of hydrogen. When the use of hydrogen becomes widespread, this risk-consciousness should not water down.
The most challenging properties of hydrogen are its high dispersability, its wide explosion limits, low ignition energy and its colourless flame.
- High dispersability and buoyancy: hydrogen rapidly diffuses and will rapidly rise in the atmosphere. This makes it dispersion when leaked from a container or system very rapid, with the potential advantage that its concentration will stay below the lower explosion limit in open environments. In closed confinements however, one should take care of the accumulation of hydrogen at ceilings of e.g. parking garages and buildings.
- Wide explosion limits and low ignition energy: hydrogen has an exceptional wide explosion range: when mixed with air, it forms an explosive mixture between 4 and 75%. In combination with an extremely low ignition energy, one should always avoid the hydrogen concentration to exceed the 4%. Proper installation of detectors is a prerequisite for safely operating with hydrogen
- Colourless flame: unlike many fuels, hydrogen burns without a visible flame, which can pose an extra hazardous situation, as burning hydrogen can remain undetected.
- Lower radiation of hydrogen burning: because burning hydrogen creates a lower radiation in comparison to other fuels, the risk of a secondary fire becomes lower.
Nedstack installations comply with all international safety standards. They have been approved by TÜV and GL (Germanischer Lloyd). In addition, Nedstack does everything to make its customers aware of the right way to use hydrogen.
The reputation of hydrogen has been wrongfully tarnished by two safety myths. It is commonly thought that the Hindenburg, the zeppelin that was destroyed in-flight by fire in 1937, burned because of the hydrogen used to float it. Instead, it was the unfortunate choice of an extremely flammable coating for the outer cover which caused the disaster. On a different track, it is sometimes feared that hydrogen can be used to create a hydrogen bomb. A hydrogen bomb requires two isotopes of hydrogen – deuterium and tritium – to collide. Commercial hydrogen gas, however, does not contain these isotopes in significant amounts. Common hydrogen gas can therefore not produce a thermonuclear reaction.