Planet Watch: Is hydrogen the fuel of the future?

David Lowe

There’s been a lot of hot air in the media recently about hydrogen. The federal government wants the gas as part of their energy road map, and the green side of politics is enthusiastic too, with certain caveats. The problem is that there’s hydrogen and then there’s hydrogen. As an energy source, things quickly get complicated where the simplest chemical element in the universe is concerned.

At standard Earth temperature and pressure, hydrogen is colourless, tasteless, odourless and non-toxic. The molecule consists of two protons and two electrons. Burning it releases energy. When used in a fuel cell, the chemical reaction between the hydrogen and oxygen creates electrical current.

Although hydrogen is the most abundant chemical substance we know of (more than half the atoms in our bodies are hydrogen, for example, along with 91 per cent of our sun), it doesn’t occur naturally in a pure form on this planet – humans have to make it. This is worth doing because of hydrogen’s very high energy content by weight, and its potential sustainability.

In 2017 the Hydrogen Council coalition (including massive players like Toyota, Hyundai and Anglo-American) told COP23 in Bonn that hydrogen had the potential to contribute 20 per cent of the abatement needed to limit global warming to two degrees C, while also creating 30 million jobs and US $2.5 trillion worth of business by 2050. The coalition predicted a tenfold increase in the production of hydrogen in the next thirty years.

So where’s all this hydrogen going to come from? That depends what colour it is

Strangely, for an invisible element, hydrogen comes in quite a few colour varieties. Presently, 95 per cent of the world’s hydrogen production is of the ‘brown’ and ‘grey’ type. ‘Brown’ refers to fossil fuels as the source ingredient (coal or methane gas, derived via natural pressure or fracking) which is treated with steam to break apart the molecular bonds of the hydrocarbons. In the process a large quantity of carbon dioxide is generated. If this is allowed to escape and pollute the atmosphere, the process is called ‘grey’.

‘Green’ hydrogen uses electricity to break apart the hydrogen from the oxygen in water (H2O) in a process called water electrolysis. More energy is required to make hydrogen this way, but if the electricity used is renewable, this is a much more environmentally sound method of production.

There’s also ‘blue’ hydrogen, in which the ‘brown’ steam methane reforming method is used, with its environmentally unsound fossil fuel recipe, but then the resulting carbon dioxide is captured, and separated from the hydrogen. Like ‘clean coal’, this process is highly problematic.

There have been successful experiments making biological hydrogen with algae bioreactors, another green process, and by using concentrated solar thermal energy.

Whichever way hydrogen is made, the main by-product of burning it in air is pure water.

Is this the energy of the future?

Compared with the best battery technology, hydrogen can release much more energy per unit of mass. That means cars and trucks running on hydrogen fuel cells can cover longer distances. Refuelling is quicker too.

Tesla CEO (and battery manufacturer) Elon Musk has described what he calls ‘fool cells’ as ‘mind-bogglingly stupid’, but there are some major players, including Toyota, who see the potential of hydrogen very differently.

With a background in applied physics, Toyota Chairman Takeshi Uchiyamada has said in response to Musk, ‘We don’t really see an adversary “zero-sum” relationship between the EV (battery powered electric vehicle) and the hydrogen car. We’re not about to give up on hydrogen electric fuel-cell technology at all.’

Another innovation is the idea of fuel stations that make their own hydrogen, using solar power, from rain gathered on the roof. Honda has even built tiny solar hydrogen stations designed for home use.

In the US, Honda and General Motors are collaborating to build hydrogen fuel cells. Ford is doing hydrogen research. California is planning to build 200 hydrogen fuel stations by 2025. In Europe, the largest green hydrogen production plant is currently in Finland, but major European players like H2Future are looking at scaling up green hydrogen to industrial levels. The Chinese government has been talking about hydrogen for transport and distributed electricity generation. In Germany there will soon be hydrogen-powered trains.

In terms of transport, hydrogen has already had a famous moment in the sun. Prior to World War II, hydrogen-filled airships built by companies like Zeppelin and others were used as luxury inter-continental passenger liners, and also by the military. Some have argued that airships should be considered again for freight uses, perhaps as giant autonomous drones.

In 1937 though, the golden age of the airship was cut short by the Hindenburg disaster, when 35 people died. Recent research suggests that the problem was initially with the skin of the airship, rather than the hydrogen itself, but however the fire started, the Hindenburg is a reminder that this gas brings unique engineering challenges. In 1986, a hydrogen leak may have contributed to the destruction of the Challenger space shuttle. The risks of hydrogen should not be underestimated.

National Hydrogen Roadmap

In Australia, the CSIRO recently delivered a National Hydrogen Roadmap which seeks to shift the narrative from ‘technology development to market activation’, arguing that the key associated technologies are now mature.

CSIRO research has made it possible for hydrogen to be transported in the form of liquid ammonia, using existing infrastructure, then reconverted back to hydrogen at the point of use using a very clever membrane. Hydrogen produced in Queensland using this technology has recently been used successfully in passenger vehicles.

Possibly the most exciting potential for hydrogen is the possibility for it to store excess renewable energy, for example in places without big batteries, and to export that renewable energy without the need for lengthy copper cables and the associated power losses.

This can be achieved at community scale, or in conjunction with large wind or solar farms, such as the planned Yara Pilbara project, or the even bigger Asian Renewable Hub, which is expected to deliver green hydrogen by 2027. The Murchison Renewable Hydrogen Project is another exciting development in Western Australia. QUT has already exported the first green hydrogen to Japan from Queensland. The Grattan Institute recently suggested that low emission, green steel is another real possibility with hydrogen, creating thousands of new jobs in the process.

Federally though, the current talk from Energy Minister Angus Taylor is all about mixing hydrogen with fossil fuel gases in existing pipelines, and extending the life of dead-end fossil fuel investments by using these substances to make brown hydrogen for export. Business as usual, in other words.

This approach needs to be called out and resisted. Hydrogen has far more positive potential than that.

Author

Originally from Canberra, David Lowe is an award-winning film-maker, writer and photographer with particular interests in the environment and technology. He’s known for his work with Cloudcatcher Media as a campaigner against unconventional gas and coal.

David has also written Australian history. Many years ago, he did work experience in Parliament House with Mungo MacCallum. David has lived off-grid in the Northern Rivers since 2008.