Hydrogen fuel: how does it work?
It was 1992 when hydrogen fuel was recognized as an alternative transportation combustible, and since then governments and international industries have been working to ensure its widespread use in fuel cell electric vehicles.
This strong interest in hydrogen fuel is due to its great efficiency as well as to zero emissions of pollutants in the atmosphere.
Tests have confirmed that a fuel cell, coupled with an electric motor, is three times more efficient than an internal combustion and carries zero emissions.
What better solution to power an electric vehicle then, especially when there is no access to electricity?
When was the fuel cell invented?
First of all, it’s important to define what a fuel cell is. In summary, it’s a device that produces electricity through an electrochemical reaction – without combustion – of hydrogen with oxygen or oxidizing agent.
The operating system is the same as a rechargeable battery, expect that the cell continuously requires a source of fuel or oxygen to sustain the reaction.
So when was the fuel cell invented?
The first device dates back to 1838, when William Grove developed its first prototype using a combination of copper, sheet metal and porcelain.
However, the first commercial use is one century later, when NASA used hydrogen technology to generate energy for satellites and space capsules.
How was hydrogen fuel made?
Despite being the most abundant element in the universe, pure hydrogen doesn’t exist in high concentrations or large quantities on Earth.
However, chemically bound hydrogen can be found everywhere: in water, hydrocarbons, fossil fuels and all living things.
This means that for using hydrogen as a transportation fuel, it’s essential to extract the element from these components, even though this process can have some environmental impacts.
How to produce hydrogen
There are two different methods to produce hydrogen:
- Electrolysis is a process that uses electricity through the water to separate the hydrogen atoms from oxygen ones. Although very effective functional, this process is little used because it requires a great deal of energy.
- Steam-methane reforming extracts hydrogen directly from natural gas and it is the most used method to produce hydrogen in large quantities. However, this reaction produces carbon monoxide and dioxide, elements that unfortunately contribute to global warming.
Still, it’s important to notice that it’s also possible to use renewable sources of energy, such as wind or sun, to produce hydrogen without emitting pollutants into the atmosphere.
This is an increasingly used approach that aims to protect the environment further
How does a hydrogen fuel cell work?
Despite the different types of fuel cell, they all work in the same way. In each cell electrochemical reaction occurs.
This is a chemical reaction as two elements combine with one another, but it’s also an electrical reaction because this combination produces electricity.
Just like a battery, the fuel cell is composed of three different parts:
- an anode;
- a cathode;
- an electrolyte separating them.
Two different chemical reactions affect these three segments consuming fuel, producing water and generating electricity.
Specifically, the anode has a catalyst that oxidizes the fuel (hydrogen) transforming it into a positive ion and a negative electron.
Electrons can’t pass through the electrolyte, so they go through a wire producing electricity, instead ions pass the electrolyte and reach the cathode where they gather on electrons.
These react lately with oxygen creating water or carbon dioxide.
How to make a hydrogen fuel cell
Once you understand the mode of operation of a hydrogen fuel cell, it’s easier to understand what elements compose it.
What is a cell made of?
The components are essentially four:
- the fuel, generally hydrogen;
- the electrolyte substance, which is the one that defines the cell type;
- the anode catalyst has the function of breaking hydrogen in ions and electrons. This element is usually made up of fine platinum powder;
- the cathode catalyst transforms ions into water or carbon dioxide, and it’s made up of nickel or nanomaterials.
To provide the right energy the hydrogen fuel cells can be combined in series, to have a higher voltage, and at the same time , to ensure a higher supply of energy.
This energy has various uses, such as:
- hydrogen vehicles;
- photovoltaic panels.
Cost of hydrogen fuel
Having established that the hydrogen fuel is environmentally friendly and more efficient than gasoline, the next question is: how much does it cost?
It’s not easy to give an exact valuation, especially if we consider that hydrogen fueling stations are spread mainly in California, so it’s very difficult to make a comparison between different markets.
However, we can roughly say that the price oscillates between $12 and $16 per gallon.
Compared to the gasoline cost, this alternative fuel is a little expensive at the moment.
The industry’s goal is to bring the price of hydrogen to down to $4 per gallon and with the aim of producing it only through sustainable energy.
Advantages of hydrogen fuel
Considering its incredible success of recent years, it’s clear that hydrogen fuel has numerous advantages over any other fuel or rechargeable battery.
But, what are these real benefits?
First of all, we know that hydrogen has the potential to move a fuel cell engine with higher efficiency than an internal combustion engine running on gasoline as the same amount of hydrogen will bring a vehicle twice as far as the gasoline.
However, beyond road performance, hydrogen fuel is also less polluting than other fuels.
Burning, this element produces only nitrogen oxides and water vapor, which carry zero emission.
Only the extraction of hydrogen produces a small amount of greenhouse gases, but in a smaller percentage of those associated with gasoline cars.
Moreover, one of the most important benefits of hydrogen fuel is the possibility to produce it domestically from many different sources, reducing dependence on gasoline and other fuels.