Hydrogen production
We have been producing hydrogen for years, but recently there has been growing interest in large-scale hydrogen projects. Hydrogen is a smart sustainable form of energy that is renewable and can be easily transported.
In addition, hydrogen is a substance we can store, to be used again later. For example, when the demand for energy is high and the generation of energy is low. Hydrogen is therefore also called an energy carrier, rather than an energy source.
Hydrogen production: how does it work?
Hydrogen is produced in a variety of ways. The colors green, blue, brown and gray are often used to indicate the source and method of production.
Gray hydrogen
Gray hydrogen is produced by a process of steam methane reforming (SMR). In grey hydrogen production, you use natural gas to split methane into hydrogen and oxygen (CO₂). CO₂ emissions in gray hydrogen production are high. This is because the oxygen is emitted into the atmosphere, which has a significant impact on the greenhouse effect. Thus, the production of gray hydrogen has a considerable negative impact on the climate.
Brown hydrogen
In addition to natural gas, coal is also used to produce hydrogen. This also releases a large amount of CO₂. Brown hydrogen is therefore also considered the least sustainable form of hydrogen production and has also become less and less popular in recent years due to this environmental impact.
Blue hydrogen
Blue hydrogen production is similar to gray hydrogen, again using natural gas. So what is different? CO₂ is captured and stored with blue hydrogen, also called carbon capture and storage (CCS). So the oxygen does not go directly into the atmosphere, as is the case with gray hydrogen. So the CO₂ emissions of blue hydrogen are much lower, but the production process here is not yet fully sustainable.
Green hydrogen
This is the most sustainable way to produce hydrogen. Green hydrogen is produced using a process called "electrolysis. In this process, we split hydrogen and CO₂ using electricity generated by a renewable energy source such as solar panels.
Environmentally friendly hydrogen production
Green hydrogen is produced by splitting water into hydrogen (H₂O) and oxygen (CO₂). We also call this process electrolysis. This electrolysis requires electricity, which we get from the sun with solar panels. Unlike gray, brown or blue hydrogen, we do not emit CO₂ when producing green hydrogen. Therefore, it is an environmentally friendly solution.
Hydrogen storage
Hydrogen storage works as follows: after we, with the help of an electrolyser, convert electricity into green hydrogen, we store it in a hydrogen battery. This stored hydrogen is later used as fuel for heavy transport and industrial processes. We are currently realizing hydrogen project H₂ Hollandia at the Vloeivelden solar park.
Storing hydrogen with solar panels
Because hydrogen is an interesting energy carrier, Novar is developing fully in this area. Hydrogen has a lot of potential energy: per kilo, for example, three times more than diesel. That offers opportunities for energy transition. Especially if we store hydrogen in combination with solar panels.
At the Vloeivelden Hollandia solar park we intend to produce green hydrogen from Q2 2024. Thanks to a direct connection with the solar park, we will not burden the electricity grid: so no problems with grid congestion.
In addition, to produce the hydrogen, we mainly use residual electricity: this is electricity that has been over-generated on sunny days. We then use the residual power, power that would otherwise have been lost, to produce hydrogen. So it's smart and effective.
Storing hydrogen: what are the possibilities
We store the hydrogen in a hydrogen battery to then transport it via tubetrailers. These are trucks with large cylinders at high pressure that allow us to transport hydrogen. This is how the hydrogen eventually goes to the end user. These include filling stations that perform heavy transportation.
In addition to storage in a battery, it is also possible to store hydrogen underground or in a liquid form. The form of storage always depends on the application.
Hydrogen: the future?
Most electrolysis plants achieve between 60% and 80% efficiency. We also see that hydrogen is still sometimes lost during transport and storage. So there are certainly still opportunities to make hydrogen storage more efficient.
Hydrogen holds great promise as an energy carrier, but depends on technological advances. The more we learn and know about green hydrogen and its storage, the more cost-efficient we can be. So there is certainly still a challenge here. A challenge we are happy to take on with hydrogen project H₂ Hollandia.