Hydrogen can serve as an “energy carrier” that offers the potential benefit of moving renewable energy (e.g. solar and wind) from places where it is abundant and cheap to places with high energy needs but less resources. For example, Australia might use its abundant solar energy resources to power “electrolyzers”, devices that break up water into hydrogen and oxygen, and then export the clean hydrogen to Japan. The Japanese could then convert the hydrogen into electricity using a device called a “fuel cell”.
As with solar energy 20 years ago, the high cost of producing hydrogen relative to carbon intensive energy carriers like oil and gas has been an impediment to adoption. But just as happened with solar, hydrogen advocates believe the cost curve will bend with greater economies of scale and technological innovation.
Now, a report on patent activity published in May by the International Renewable Energy Agency (IRENA) provides tangible support for the notion that the cost of water electrolysis (the process of breaking water into hydrogen and oxygen) will continue its downward trajectory.
Overall, the report highlights that international granted patents for water electrolysis rose consistently from a negligible number in 2005 to 3,972 in 2020 (and 2,817 in just the first six months of 2021). With the US, Japan and Germany accounting for just over 50% of those grants, the report breaks the patents into five categories. Four of these relate to increasing the durability and efficiency of different components of an electrolyzer as well as reducing the use of scarce noble metals and other expensive materials. Of these various improvements, efficiency may be the most important as renewable energy inputs currently account for around 70% of the cost of clean hydrogen.
Interestingly, a fifth category comprises patents for photoelectrolysis, a process that offers the promise of huge efficiencies because hydrogen is produced from water using direct sunlight rather than an electric current generated by solar or wind power. Photoelectrolysis patents began to accelerate in 2015 but most of these patents have been filed by universities suggesting the technology may be further from its commercialization phase.
The impact of these patented technologies is already being felt as electrolyzer manufacturers roll out next generation models with higher capacity, more pressure, longer lives, more efficient and lower cost membranes and catalysts and more compact designs. The record number of additional patents granted in recent periods is a signal that R&D spending continues to generate valuable innovations which will feed the virtuous cycle of declining costs and adoption.