Columnists
Green hydrogen, another opportunity for renewable energy investments
Friday March 17 2023
Back to your high school Chemistry lessons , you will recall how water was split into hydrogen (H) and oxygen (O) through a process called electrolysis.
You also learned that you can burn hydrogen in the air to produce heat (energy) while producing water.
The same syllabus taught that hydrogen can be combined with nitrogen(N) from the air to form ammonia(NH3), a key ingredient for the manufacture of ammonium fertilisers.
It is this simple chemistry of abundantly and freely available materials that is undergoing commercial scale-up to produce “green” hydrogen fuel and fertilisers.
“Green” denotes hydrogen produced using renewable electricity (solar, wind, geothermal and hydro) to electrolyse water. This essentially means using green electricity to produce green fuel (hydrogen) with a virtually zero carbon footprint.
This is in contrast to “grey” hydrogen, which is produced by splitting hydrocarbons (natural gas), a process which produces carbon dioxide.
Production and use of green hydrogen is a rapidly evolving energy transition technology contained in most energy production masterplans, especially in Europe and China.
It is in auto transportation competing with electric vehicles, while it is seen as the future green fuel in marine transportation. Due to its high burning temperatures (plus 2000 degree Celsius), hydrogen is an energy transition frontrunner as an industrial heating fuel to replace coal, oil and natural gas in heavy industries like steel and cement manufacturing.
The downside of green hydrogen includes high production unit costs, as electrolysis essentially involves using energy to produce another form of energy. Being a light gas, distribution and storage infrastructure costs for hydrogen is high.
Recently, the European Investment Bank announced some 1.8 million euros to kick-start green hydrogen investments in Kenya.
The most ready entry points for green hydrogen investment in Kenya are industrial heating and fertilisers. Nearly all industries today use imported high-carbon fuel oil and coal for heating.
For those industries located near good supplies of water, solar-produced electricity can generate green hydrogen for heating. The same applies to fertiliser manufacturing opportunities.
Directionally, generation of hydrogen should be from greenfield renewable electricity plants to avoid tapping from national grid, which is incrementally fed from expensive high-carbon fossil fuels. Site selection for green hydrogen projects should also seriously consider impacts on water resources.
Green hydrogen is joining a multitude of renewable energy technologies which are gradually finding their space in Kenya. These should be correctly reflected in our energy policies and regulatory and fiscal frameworks to support investments.
George Wachira is a petroleum consultant, [email protected]