Is hydrogen the fuel of the future?

Hydrogen will play a key role in the transition to a planet the runs on clean energy, but scaling up production is a major challenge currently facing the world’s engineers, investors, and governments, according to Australia’s chief scientist, Alan Finkel.

At the World Engineers Convention 2019, Finkel and Paul Durrant, head of innovation strategies at the International Renewable Energy Agency (IRENA) hosted a discussion about whether hydrogen is the fuel of the future.

“Hydrogen used as a fuel, as an energy carrier, is critical to our collective ability to tackle the climate emergency and to contribute on several sustainable development goals,” Durrant said.

A key driver of interest in hydrogen identified by IRENA is the dramatic fall in price of renewable energy in recent years.

“As a result, renewables are already the lowest cost source of new power generation in many parts of the world today,” he said.

“By early next year, onshore wind and solar photovoltaic will join hydropower in consistently offering cheaper sources of electricity.”

Some of the issues facing renewables are the variable nature of energy production, especially at low levels of deployment, and the need to be able to store energy for potentially long periods of times.

In addition, Durrant said that some of the applications that involve the direct use of electricity is not a viable option, such as the building, industry, and transport sectors.

“Together, these account for about 60 per cent of the direct energy-related carbon dioxide emissions. Electricity can address some of those, but we need molecules as well as electrons in our energy mix if we are really going to decarbonise,” he said.

Dr Finkel, who presented at the event via video, said that there is no limit on the amount of solar and wind energy we can tap into, but it’s not always continent and that hydrogen could act as a high-density transport or fuel to solve this issue.

However, there is no free hydrogen on earth – it isn’t possible to drill a hole and extract it like natural gas – meaning it needs to be produced.

“The way that most of us are excited about is to produce it through a combination of solar, wind and water taken into electrolyser or electrolysis unit,” Finkel said.

“The challenge is to make it economical in really large volumes. We’re not talking about doing a beaker in a lab class every second, we’re talking about doing swimming pools of water every second.”

Three types of producing hydrogen labelled as colours were also discussed in the presentation, with Durrant emphasising the importance of moving away from fossil-fuel based production of hydrogen, also known as grey hydrogen.

Fossil-fuel based production of hydrogen with carbon capture storage and utilisation is known as blue hydrogen and renewable-based production of hydrogen, namely water electrolysis, is known as green hydrogen.

“Crucially, as we scale up, we need to avoid getting locked into high energy processes that lead to stranded assets or we will still be making emissions for decades to come,” Dr Durrant said.

“We need to start shifting the existing production from grey, to blue, or better still green, and crucially ensure future hydrogen production is not grey hydrogen.”

The discussion came as Finkel released the National Hydrogen Strategy, which was adopted by a meeting of COAG energy ministers on November 22. The Strategy sets a roadmap for the development of a hydrogen industry in Australia, and will guide governments in its implementation to 2030 and beyond.