🚀 Hydrogen, fuel of the future ? Part 1
The opportunities and challenges of hydrogen in the energy transition. Part 1 of 2.
3 … 2 … 1 … Liftoff!
On July 16, 1969, three astronauts—Neil Armstrong, Buzz Aldrin, and Michael Collins—embarked on a historic journey to the moon aboard the Saturn V rocket. Standing 110 meters tall and weighing 2,900,000 kilograms, the mechanical giant was partly powered by hydrogen!
Saturn V schematics (left) and Von Braun with its F-1 engines (right). Source: Wikipedia.
Half a century later, hydrogen is making a comeback, this time as a miracle fuel for the energy transition. In this edition of Seagnal, a newsletter at the intersection of technology and sustainability, we will explore the role and opportunities for hydrogen in the energy transition. Next week, in part 2, we'll examine the challenges it faces.
Hydrogen energy 101
Hydrogen, the lightest known element, can be used to produce energy, such as electrical energy using fuel cells, or kinetic energy using combustion. The beauty of using hydrogen is that the main byproduct of its chemical reaction is water:
That’s pretty handy. So why aren’t we using more hydrogen instead of fossil fuels to power our cars and to make electricity?
While hydrogen is the most abundant chemical substance in the universe, it does not occur naturally on Earth in large quantities: most of it is in the form of water (Hâ‚‚O).
That’s why hydrogen is considered an energy carrier and not a primary energy source. Unlike natural gas, found in Earth’s crust, which is both a primary energy source and an energy carrier, hydrogen is made.
Today, most of the hydrogen we produce comes from natural gas through a process called steam reforming, which emits carbon dioxide (COâ‚‚) as a byproduct. Hydrogen produced this way is called grey hydrogen, or blue hydrogen when the COâ‚‚ is (mostly) captured - see carbon capture and storage.
However, cleaner hydrogen production methods like electrolysis, which uses electricity to split water into hydrogen and oxygen, are gaining traction. When electrolysis is powered by renewable energy sources, we call it green hydrogen. And the color spectrum fun doesn’t end there:
Hâ‚‚ production colors, from Techno-Economic Analysis of the Available Technologies for Hydrogen Production.
Now that we understand hydrogen is an energy carrier that can be generated through various methods, each with distinct environmental impacts, we will explore hydrogen applications in the energy transition, starting with electricity generation.
Leveraging Hâ‚‚ to decarbonise the grid
Today, most countries rely on gas or coal in their power generation mix to compensate for the daily and seasonal fluctuations of intermittent renewable energy sources. Below, you can see the hourly, daily, and monthly power generation mix in California.
Hourly (from June 10/11), daily and monthly mix of the Californian (CAISO) power generation mix. From Electricity Maps.
From these graphs we can see:
Hourly (left graph): Gas (red), hydro (blue), and batteries (purple) compensate for the significant drop in solar (orange) energy in the evening.
Daily (middle graph): Gas compensates for days with low wind (turquoise).
Monthly (right graph): Gas offsets the seasonal variations in wind and solar energy, such as reduced sunlight in winter.
Green hydrogen, though currently more expensive than cheap American natural gas or Australian coal, has the potential to replace these fossil fuels without the pollution. This makes it an ideal candidate for use in peaker plants—facilities designed to provide peak power quickly and efficiently when demand surges, or intermittent supply falls (or both).
Hydrogen can be used as a COâ‚‚-free energy carrier, complementing batteries and pumped-hydro, to convert excess renewable energy into a transportable and storable energy medium. It can then be used, like gas and coal peaker plants, alongside batteries and hydro, to ensure a flexible energy supply to the grid.
Leveraging Hâ‚‚ to decarbonise other sectors
There are many challenges for hydrogen to become a cost-effective player in the power generation sector. While electricity generation is the heart of the energy transition, clean hydrogen can also decarbonize other sectors.
For instance, it can play a crucial role in reducing emissions in the steel-making industry, which accounts for 7% of global greenhouse gases (GHG) emissions, and the fertilizer industry, responsible for 1.5% of global GHG emissions.
The hydrogen ladder version 5.0, CC-BY 4.0 source
The hydrogen ladder (pictured above), is a nice representation of all the hydrogen opportunities, ordered in terms of likely market share (full methodology here). A simple heuristic for the ladder is that hydrogen could have a good market share penetration in anything that can’t be electrified.
These sectors cannot be electrified due to process requirements such as high heat and chemical reactions that electricity can’t satisfy. In some of these sectors, like fertilizer production, there are currently no carbon-neutral alternatives to green or pink hydrogen. In other sectors, such as jet aviation or shipping, hydrogen will compete with biomass.
However, for green hydrogen to be widely adopted in any of these applications, it must become cost-effective to produce, store, and transport. While we will explore these challenges next week, here’s a teaser: current production costs indicate that green hydrogen must first become competitive with grey and blue hydrogen.
Average hydrogen production cost 2023 by color, source.
Hydrogen in the energy transition, recap.
Hydrogen holds promise as a versatile and clean energy carrier. While it doesn't naturally occur on Earth in large quantities it can be produced from a variety of sources, classified by colors such as green, grey and blue hydrogen.
Green hydrogen, produced with electrolysis powered by renewable energy, could be used to decarbonise some electricity generation (eg. peaker plants), certain industrial processes (eg. fertilisers and steel-making), and some transportation use cases (eg. jet aviation and shipping). Furthermore, just like natural gas, green hydrogen is a way for countries to export energy as a commodity (competing with interconnected grids).
Next week we will look into the challenges green hydrogen is facing, to determine if it truly is the fuel of the future!
From San Fransisco 🇺🇸,
Jean
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