The red flags in green hydrogen

The red flags in green hydrogen

28 May 2023 - Ufrieda Ho

Scientists can do better to take industry and government-driven hype out of green hydrogen so that its actual potential can be realised.

Green hydrogen's outsized promise to meet the world's decarbonisation agenda, while being a reliable fuel that keeps Big Industry's growth targets on track, is dazzling. But experts caution that the dazzle is distraction and questions need to be asked about how much of green hydrogen's promise is oversell, and how much is actual potential.

Hydrogen is a gas that has no colour, odour, or taste. It is a very simple element because its atom has only one proton in its nucleus. Green hydrogen is defined as hydrogen produced by splitting water into hydrogen and oxygen using renewable electricity.

A gap for green

South Africa, like many other countries, has joined the green hydrogen rush, pinning hopes on this being a so-called "big frontier", as President Cyril Ramaphosa called it, for a just energy transition. Ramaphosa said at that Green Hydrogen Summit in November 2022 that green hydrogen has "huge growth and investment potential as demand for green hydrogen products around the world increases."

For green hydrogen to deliver on its promise means it must significantly help meet the world's recognised target to reduce carbon emissions by 45% by 2030, and to be at net zero by 2050. This is what scientists say is needed if the planet is to have a chance to limit global warming to 1.5 degrees Celsius above pre-industrial levels.

To date, the route to curbing carbon emissions has centred on renewable energies such as solar and wind. But key challenges persist around scale, intermittent supply, and long-term energy storage. These shortcomings have opened a gap for green hydrogen.

A dirty rainbow

Hydrogen is the most abundant element in the universe, with green hydrogen promising to be clean burning, more efficiently stored, and transportable. Add to this a mighty push from oil and gas monopolies (which still control all grades of hydrogen production) and green hydrogen has been elevated to a star role to stave off the climate catastrophe. But there are catches.

Hydrogen production is only considered "green" when it is produced through water electrolysis from electricity that's fuelled from renewable sources - such as wind and solar. Hydrogen production follows a rainbow of grades with green hydrogen at one end, and grey and black hydrogen, which is produced from burning fossil fuels, at the other "dirty" end. This means that green hydrogen production is contingent on a solid renewable energy framework that has surplus supply.

Dr Bruce Young is a Senior Lecturer in the African Energy Leadership Centreat Wits Business Schooland has worked in the petro-chemical business for decades. Young says that green hydrogen has been too hastily cast as the "saviour to our energy woes - a Swiss army knife of energy transition, which can be used for so many things". He is doubtful that the green hydrogen hype matches its touted potential for all these applications. There are often better alternatives for many of these applications, particularly the direct use of renewable electricity.

Volume leaks, storage limitations

Green hydrogen's limitations, Young outlines, are that the current production volume is "very small", with most hydrogen produced being of the carbon-intensive grey and black hydrogen variety.

Green hydrogen also needs conversion to higher energy density products, such as ammonia, so it can be stored and transported over long distances, and to be cost effective - Young says that mega green hydrogen production plants have capital costs in the billions of dollars, and protracted timeframes over decades.

In addition, there is hydrogen leakage to contend with. Hydrogen, being the smallest molecule, is prone to leakage and in the atmosphere, it acts as an indirect greenhouse gas, adding to global warming.

"Green hydrogen technology has no meaningful installed capacity and will take decades to scale up, to refine, and to make it efficient at a multi-gigawatt scale. Currently, the first gigawatt scale pioneering project planned in Saudi Arabia will begin production only in 2026 and it will inevitably have its own start-up issues, as is inherent in pioneering plants."

Burial and blue hydrogen

Young says that the oil industry is proposing the use of blue hydrogen as an interim measure. This involves burying the carbon dioxide produced by grey hydrogen production underground, using carbon capture and storage (CCS) technology.

"Bold forecasts have been made about CCS technology in the past, which have not materialised, and it is costly with only a small number of projects in operation worldwide," says Young.

More pertinent, Young says the renewed attention on green hydrogen should raise questions of who stands to gain from a green hydrogen boom, taking into consideration the consequences of clouded decision-making and poor investment choices for energy transition plans - South Africa's included.

"The oil and gas industry has a strong vested interest in promoting green hydrogen to try and ensure their survival. Using hydrogen as a fuel fits with the oil companies' current business model - they control the fuel production, supply and the wholesale and retail distribution of hydrogen fuel," Young says.

Commodifying energy

The benefits of green hydrogen, in real terms, come down to appropriate applications. It's a good choice for nitrogenous fertiliser production, hydrogenation and desulphurisation, for example, but not for domestic heating, jet fuels, or running cars, for which better alternatives exist.

Similar warnings come from Dr Neil Stacey, a Lecturer in the School of Chemical and Metallurgical Engineering. Stacey calls for vigilance, pointing out that the incentives of the major stakeholders do not align with the public interest.

"Energy, in most of its forms, is a centrally controlled commodity produced by a handful of companies and regulated by governments for which energy access is a powerful political tool. Renewable energy disrupts that paradigm by democratising energy access, threatening major sources of revenue and political power. Major corporations and governments share an incentive to either prevent that shift or steer it in a direction that favours their vested interests. And, in the current environment of social media, the tools for influencing public opinion are more potent than ever before," Stacey says.

Renewable energy required

In November 2022, the South African government announced a R300-billion investment pipeline as part of the country's Green Hydrogen National Programme. Ramaphosa said then that South Africa could produce up to 13 million tonnes of green hydrogen and derivatives by 2050 but would need 300 gigawatts of renewable energy. According to the Council for Scientific and Industrial Research (CSIR), as of 2021, renewable energy contribution to installed capacity in the country stood at 5.7 gigawatts and contributed to 6.6% of the country's total energy mix.

Even the pioneering plant in Saudi Arabia (which bills itself as what will be the largest plant to produce green hydrogen in the world) expects at full operation to produce 600 tonnes of carbon-free hydrogen a day. In a year that would be just over 200 000 tonnes. To get to Ramaphosa's 13 million tonnes, at its expected output rate in 2026, would take this mega plant around 60 years to achieve.

For Stacey this "overhyping and over-investment in hydrogen" also has the effect of co-opting research capacity into hydrogen and away from other renewable energy innovations, including on recycling technologies to ensure renewable energy equipment doesn't end up in landfills at the end of its life.

Research redirection risks

"There is a risk of academia becoming an extension of government and corporate interests, rather than a balance against them. Scientists are incentivised to obtain funding and to get their work published and cited, and that means playing along rather than ringing alarm bells," says Stacey.

The big numbers quoted need more unpacking, and it also means that South Africa's credit from concessional loans for the just energy transition plan cannot be squandered.

"In the best-case scenario, South Africa uses the money to move more swiftly to neat, elegant solutions, like widespread rooftop solar and a good basket of energies that may be high on capital investment but are low on operating costs," says Stacey.

In his worst-case scenario, more people remain without access to electricity in South Africa and generational debt sets in.

"It comes down to making good sensible choices where we match the supply of energy to its demand and we ensure that no one gets left behind," Stacey says.

• Ufrieda Ho is a freelance writer.
• This article first appeared in Curiosity, a research magazine produced by Wits Communications and the Office of the Deputy Vice-Chancellor: Research and Innovation.
• Read more in the 15^th issue, themed: #Energy. We explore energy research into finding solutions for SA's energy crisis, illuminate energy needs of people with disabilities, address the energy and digital divide in an unequal society, and investigate the origins of fire control.

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