Hydrogen’s future in South Africa: The hydrogen generator explained
Experts say that hydrogen is one answer to South Africa’s greenhouse gas emissions problem. It has the potential to speed up South Africa’s decarbonisation efforts and create thousands of jobs.
One way of producing hydrogen involves the use of hydrogen generator technology. This technology could prove instrumental, as South Africa is under increasing pressure to decarbonise. This is because the country is the 12th largest emitter of carbon dioxide. While it has reduced its emissions targets to align with global targets of reducing warming to 1.5°C by the end of the century, experts warn that this is not enough.
How hydrogen gas is produced
Hydrogen is the most abundant element in the universe. However, it does not occur on its own, naturally. Hydrogen must be separated from other chemical compounds using energy. There are a number of ways of doing this, including the below.
These processes use the energy from resources like natural gas, coal or biomass to release the hydrogen they contain. Heat and chemical reactions can also be used to produce hydrogen from elements like water.
This is when electricity is used to split water into its components: hydrogen and water.
This is when microbes, like bacteria, produce hydrogen through biological reactions. They do so using organic matter or sunlight.
Different types of hydrogen that we can produce
There are four types of hydrogen:
- Brown hydrogen. This is produced when heat and chemical reactions are used to release hydrogen from fossil fuels, like coal. This process produces a lot of pollution, and this type of hydrogen production is responsible for carbon dioxide emissions that equal those of Indonesia and the UK combined.
- Grey hydrogen. Similar to brown hydrogen, the gas is released when heat and chemical reactions are applied to natural gas. Natural gas is also a fossil fuel, and this process is also polluting.
- Blue hydrogen. This process is identical to the production of grey hydrogen but with one exception: the carbon dioxide emissions are captured by carbon capture and storage technologies.
- Green hydrogen. In this process, electrolysis is used to separate hydrogen from water. While this process does not emit carbon dioxide directly, the hydrogen is only considered green if the electricity used comes from renewable sources, like wind and solar power.
Using a hydrogen generator to produce hydrogen through electrolysis
One way of producing hydrogen through electrolysis is to use a hydrogen generator. This machine is a safer and more user-friendly alternative to storing and transporting hydrogen in cylinders.
Hydrogen cylinders can be dangerous due to the high risk of explosion. This is especially problematic for scientists working in laboratories. However, a hydrogen generator has a number of safety mechanisms in place to prevent explosions in the event of a hydrogen leak – unlike cylinders – and can produce hydrogen on-site.
How a hydrogen generator works
A hydrogen generator contains a cell where electrolysis takes place. Inside the cell, two opposing catalysts are separated by a membrane. Hydrogen and oxygen are attracted to these catalysts. As a result of this attraction, the oxygen and hydrogen molecules separate, making it possible to extract the hydrogen.
Types of hydrogen generators
A number of different hydrogen generators are on the market. Some are remotely operated and controlled by individual operators at centralised service centres. Others can be used in meteorology and power plants, as well as chemical processing.
Hydrogen generator technology use in South Africa
Hydrogen fuel technology in South Africa is in the early stages of being rolled out. But, it is the subject of much research and innovation in the country. While individual hydrogen generators can be purchased for laboratory and other uses, their large-scale commercialisation has not yet begun.
But, that is changing. The South African government plans to develop the hydrogen economy in the country, and much research has gone into how this can be done. This includes the use of hydrogen generators.
In 2015, researchers at the University of the Western Cape’s Hydrogen South Africa Systems Centre of Competence launched a prototype hydrogen fuel cell generator. The generator was able to provide electricity on-site to one of the university’s buildings. Its developers said that the generator could be used anywhere where a maximum of 2.5 kilowatts of electricity was required.
The South African government plans to introduce hydrogen fuel cell technology, especially green hydrogen, into the economy by rolling out a “hydrogen valley” in selected parts of the country. Undoubtedly, hydrogen generators will play their part in this too.
The effect of hydrogen production on our atmosphere
While green hydrogen is seen as an important fuel for decarbonisation, scientists warn that the impact of hydrogen on the atmosphere and the climate are not yet fully understood. This is because ozone and water vapour react with sunlight to produce hydroxyl radicals. These chemicals act as scrubbers in the atmosphere, helping to remove other chemicals like methane – a powerful greenhouse gas.
But, when hydrogen is released into the atmosphere, it reduces the amount of hydroxyl radicals. This could have a negative effect on efforts to combat global warming. Therefore, scientists are concerned that replacing all fossil fuels with a hydrogen economy without enough research on the subject could result in global warming.
Scientists say that hydrogen leakage is a major problem that needs addressing, and more research into how hydrogen impacts the atmosphere is required. This includes how land absorbs hydrogen.
The future of hydrogen generator technology in South Africa
While this research is ongoing, hydrogen remains a potential fuel that is under intense consideration in South Africa and abroad. A report found that the potential value to South Africa’s gross domestic product of the mooted hydrogen valley could reach over USD $8 billion. With their advantage over cylinders, hydrogen generators will likely form a key part of the rollout of this technology.