by Sieb RodenburgHi, my name is Sieb Rodenburg. I am the scalability manager of Eco-Runner Team Delft. On this page I want to summarize the subject hydrogen. Although I’ve got a strong opinion about most topics around hydrogen, I’ve tried to give a clear picture of what it is and why it’s so important for the energy transition. I’ve tried to use as many independent and up-to-date sources as possible, like TNO, The Wuppertal Institut or the International Energy Agency (IEA).
I always love to talk about hydrogen and the energy transition, so feel free to contact me if you have any questions or want to collaborate. If you want to dig even deeper into the subject then please listen to our podcast ‘De Waterstofpodcast’ where we discuss hydrogen with experts in the field. The podcast is in Dutch and is available on Spotify, Apple, or Google podcasts.
What is hydrogen?
Hydrogen is the first and simplest atom in the periodic table and consists of one proton and one electron. It is also the most abundant element on earth. When we speak of hydrogen we tend to mean dihydrogen, meaning two hydrogen atoms forming a molecule as seen below. However, this form of hydrogen does not occur naturally on earth. In nature hydrogen is always coupled with another element, for example oxygen in water or carbon in natural gas or oil. With different kinds of techniques you can subtract the hydrogen from its original form.
Currently the most used method to win hydrogen is steam methane reforming, in which methane is divided into CO₂ and hydrogen with steam. This CO₂ is emitted into the atmosphere, and is therefore called grey hydrogen. We can already capture this CO₂ and store it underground in for example old gas fields, which saves 80-90% of CO₂ emissions. (TNO, Peters, 2020) When this is done we call it blue hydrogen. Of course this way of producing hydrogen is still not future proof, because fossil fuels are still used in the process. To make sustainable hydrogen, also known as green hydrogen, we use renewable electricity for example from windmills or solar panels. With this electricity water is divided into hydrogen and oxygen in a machine called an electrolyser.
Even though hydrogen is seen as an energy carrier of the future, hydrogen production already plays a big role in our energy mix, taking up 6% of our total natural gas use and 2% of our coal use globally. (IEA, 2020) The biggest consumers are oil refineries and the fertilizer industry.
In the future, hydrogen will become important in all sections of our life. It will grow very large in industry, as a feedstock, but also for high temperature processes. It will play an important role in mobility, especially in heavy and long-haul transportation, such as for trucks, busses, trains, boats and airplanes. It can play a role for spatial heating of our homes and other buildings, where electrification or a heat grid will not be sufficient. It will become a crucial factor in moving and storing energy, since hydrogen is both easier and cheaper to store or move compared to electricity.
These are only just a few examples for hydrogen’s wide variety of possible applications, so do not forget to scroll through our website and discover the wonders of hydrogen and hopefully you will get inspired to work or investigate in the field of hydrogen as well.
Where did it all begin?
The first applications of hydrogen were seen in for example the hippomobile, one of the first ever combustion engine vehicles. This car was driven on a mix of hydrogen and carbon monoxide, which was a product made from coles. Another early use was in zeppelins. Both hydrogen and helium are lighter than air, which makes it possible to let a zeppelin fly. A famous zeppelin with a not so happy ending that flew on hydrogen was the Hindenburg, a zeppelin that flew between Germany and the United States before the second world war. The Hindenburg crashed into an electricity cable and caught fire. A fable is that this was caused by the hydrogen, but is more likely that the skin and wooden body burned, because hydrogen rises with a speed of around 20 m/s and therefore had already disappeared before it could burn. Another famous use was in space exploration. Except for a lot of kerosine and liquid oxygen, the Saturn V rocket that brought the Apollo 11 to the moon used more than 1.2 million liters of liquid hydrogen. The Eco-Runner X would be able to drive to the moon and back 285 times with this amount of hydrogen.
How safe is hydrogen?
Hydrogen is a combustible gas, and is therefore feared sometimes. The most dangerous features of hydrogen are its flammability and ignition limits. Hydrogen can ignite in a hydrogen-oxygen mixture between 4-77%, compared to an ignition range of beneath 20% for most fossil fuels. This asks for safe handling of hydrogen, but because it is already used in industry for so many years, all this knowledge is available and ISO standards have therefore long been made. Since 2015 standards have also been set on safe handling of hydrogen in cars and other applications. (ISO/TC 197)
Because we are used to using fossil fuels for over 100 years now, we are accustomed to dealing with them but tend to forget the dangers. Oil or natural gas are both very dangerous substances. A petrol leak will for example pool close to the ground, largely increasing incineration likelihood. If a leak occurs in a hydrogen tank the very volatile hydrogen will escape into the air quickly, not causing this extra danger. The advantage of the volatility can also be seen in the ignition experiment below, conducted by the US department of energy. For domestic usage hydrogen is also safer than natural gas. It diffuses 6 times quicker and is less toxic when breathed in. Just like natural gas hydrogen is scentless, so an indicator will be added when moving hydrogen into our homes.