On the edge of the Saudi Arabian desert beside the Red Sea, a futuristic city called Neom is due to be built. The $500bn (£380bn) city – complete with flying taxis and robotic domestic help – is planned to become home to a million people. And what energy product will be used both to power this city and sell to the world? Not oil. Instead, Saudi Arabia is banking on a different fuel – green hydrogen. This carbon-free fuel made is from water by using renewably produced electricity to split hydrogen molecules from oxygen molecules.
This summer, a large US gas company, Air Products & Chemicals, announced that as part of Neom it has been building a green hydrogen plant in Saudi Arabia for the past four years. The plant is powered by four gigawatts of electricity from wind and solar projects that sprawl across the desert. It claims to be the world’s largest green hydrogen project – and more Saudi plants are on the drawing board.
The Saudis aren’t alone in seeing green hydrogen as the next big thing in energy. While the fuel is barely on the radar in the United States, around the world a green hydrogen rush is underway, and many companies, investors, governments and environmentalists believe it is an energy source that could help end the reign of fossil fuels and slow the world’s warming trajectory.
Hydrogen already powers some large transport such as trains in countries such as Germany and the UK, but getting clean, green hydrogen is still a challenge (Credit: Getty Images)
“It is very promising,” says Rachel Fakhry, an energy analyst for the Natural Resources Defense Council, a non-profit organsiation based in New York. Experts like Fakhry say that while wind and solar energy can provide the electricity to power homes and electric cars, green hydrogen could be an ideal power source for energy-intensive industries like concrete and steel manufacturing, as well as parts of the transportation sector that are more difficult to electrify. “The last 15% of the economy is hard to clean up – aviation, shipping, manufacturing, long-distance trucking,” Fakhry says. “Green hydrogen can do that.”
Green hydrogen holds a vice-like grip over the imaginations of techno-optimists – Michael Liebreich
Europe, which has an economy that is saddled with high energy prices and is heavily dependent on Russian natural gas, is embracing green hydrogen by providing funding for construction of electrolysis plants and other hydrogen infrastructure. Germany has allocated the largest share of its clean energy stimulus funds to green hydrogen. “It is the missing part of the puzzle to a fully decarbonised economy,” the European Commission commented on its hydrogen strategy.
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Hydrogen’s potential as a fuel source has been touted for decades, but the technology has never gotten off the ground on a sizeable scale – and with good reason, according to sceptics. They argue that widespread adoption of green hydrogen technologies has faced serious obstacles, most notably that hydrogen fuels need renewable energy in order to be green. This will require a massive expansion of renewable generation to power the electrolysis plants that split water into hydrogen and oxygen. In contrast, at present the most common way to produce hydrogen remains “natural gas reforming”, which as its name suggests requires a fossil-fuel input in the form of natural gas, which is reacted with steam to produce hydrogen, carbon monoxide and carbon dioxide. Because CO2 is emitted in this traditional manufacture of hydrogen from methane, it’s not climate friendly; hydrogen produced this way is known as “grey hydrogen”.
Hydrogen fuel cells will power the future of zero-emission mobility in heavy-duty, hard-to-electrify sectors – Roxana Bekemohammadi
And, regardless of the method of production, hydrogen is also hard to store and transport without a pipeline. And right now in some places, such as the US, hydrogen is a lot more expensive than other fuels such as natural gas.
October 2020 saw the launch of the world's first double-decker hydrogen-powered bus in Aberdeen, Scotland (Credit: Getty Images)
While it has advantages, says Michael Liebreich, a Bloomberg New Energy Finance analyst in the UK and a green hydrogen sceptic, “it displays an equally impressive list of disadvantages”.
“It does not occur in nature so it requires energy to separate,” Liebreich writes in the first of a pair of recent essays for BloombergNEF. “Its storage requires compression to 700 times atmospheric pressure, refrigeration to -253C… It carries one quarter the energy per unit volume of natural gas… It can embrittle metal, it escapes through the tiniest leaks and yes, it really is explosive.”
Some green hydrogen projects are learning this the hard way. An energy consortium in Australia recently announced plans to export green hydrogen from a site in Pilbara in western Australia to Singapore. The scheme involved 1,743 large wind turbines and 30 square miles of solar panels to run a 26-gigawatt electrolysis factory to create its green hydrogen. But the facility, called the Asian Renewable Energy Hub, has noted that ammonia may be a more realistic gas to export than hydrogen, due in part to the difficulties of transporting hydrogen over such long distances, ABC News reported.
In spite of problems such as these, Liebreich writes, green hydrogen still “holds a vice-like grip over the imaginations of techno-optimists”.
Ben Gallagher, an energy analyst at Wood McKenzie who studies green hydrogen, says the fuel is so new that its future remains unclear. “No one has any true idea what is going on here,” he says. “It’s speculation at this point. Right now, it’s difficult to view this as the new oil. However, it could make up an important part of the overall fuel mix.”
But for proponents, the prospect of green hydrogen is too tantalising to ignore. If manufactured with renewable energy, it’s CO2-free. Moreover, using renewable energy to create the fuel can help solve the problem of intermittency that plagues wind and solar power, and so it is essentially efficient storage. When demand for renewables is low, during the spring and fall, excess electricity could be used to power the electrolysis that is needed to split hydrogen and oxygen molecules. Then the hydrogen can be stored or sent down a pipeline.
Across Europe, the Middle East and Asia, more countries and companies are embracing this fuel. The US lags behind because other forms of energy, such as natural gas, are currently much cheaper, but several new projects are getting underway, including a green hydrogen power plant in Utah that will replace two aging coal-fired plants and produce electricity for southern California and Nevada, as well as for use within Utah.
While proponents are optimistic about green hydrogen's future, sceptics question how easy it is to transport the fuel safely (Credit: Getty Images)
In Japan, a new green hydrogen plant, one of the world’s largest, just opened near Fukishima – an intentionally symbolic location given the plant’s proximity to the site of the 2011 nuclear disaster. It will be used to power fuel cells, both in vehicles and at stationary sites.
As Europe intensifies its decarbonisation drive, it, too, is investing in green hydrogen. The European Union recently drafted a strategy for a large-scale green hydrogen expansion, though it hasn’t been officially adopted yet. But in its clean energy plan, in which it envisages investment of up to its €470bn ($550bn/£415bn) in the fuel, the EU is including funds for new green hydrogen electrolysers and transport and storage technology. “Large-scale deployment of clean hydrogen at a fast pace is key for the EU to achieve its high climate ambitions,” the European Commission wrote.
The Middle East, which has the world’s cheapest wind and solar power, is angling to be a major player in green hydrogen. “Saudi Arabia has ridiculously low-cost renewable power,” says Thomas Koch Blank, leader of the Rocky Mountain Institute’s Breakthrough Technology Program. “The sun is shining pretty reliably every day and the wind is blowing pretty reliably every night. It’s hard to beat.”
BloombergNEF estimates that to generate enough green hydrogen to meet a quarter of the world’s energy needs would take more electricity than the world generates now from all sources, and an investment of $11tn (£8.3tn) in production and storage. That’s why the focus for now is on the 15% of the economy with energy needs not easily supplied by wind and solar power, such as heavy manufacturing, long-distance trucking, and fuel for cargo ships and aircraft.
The energy density of green hydrogen is three times that of jet fuel, making it a promising zero-emissions technology for aircraft. But Airbus, the European airplane manufacturer, recently released a statement saying that significant problems need to be overcome, including safely storing hydrogen on aircraft, the lack of a hydrogen infrastructure at airports, and cost.
“Cost-competitive green hydrogen and cross-industry partnerships will be mandatory to bring zero-emission flying to reality,” says Glen Llewellyn, vice president of Zero Emission Aircraft for Airbus. He is optimistic that it can happen, believing that hydrogen-powered aircraft could be flying by 2035.
Countries around the world have been stepping up investment in green hydrogen, from Japan to Australia and the US to Germany (Credit: Getty Images)
And on the ground, green hydrogen has also been identified as an alternative to some road vehicles. In the UK, hydrogen trains, trucks and double-decker buses are gaining traction. While in California, the state passed a Low Carbon Fuel Standard back in 2009 to promote electric vehicles and hydrogen vehicles. In October, a group of heavy-duty vehicle and energy industry officials formed the Western States Hydrogen Alliance to press for rapid deployment of hydrogen fuel cell technology and infrastructure to replace diesel trucks, buses, locomotives, and aircraft.
“Hydrogen fuel cells will power the future of zero-emission mobility in these heavy-duty, hard-to-electrify sectors,” says Roxana Bekemohammadi, executive director of the Western States Hydrogen Alliance. “That fact is indisputable. This new alliance exists to ensure government and industry can work efficiently together to accelerate the coming of this revolution.”
There are even plans for smaller scale hydrogen systems that can power individual homes. In Australia, the University of New South Wales, in partnership with the global engineering firm GHD, has created a home-based system called LAVO that uses solar energy to generate and store green hydrogen, which is converted back into electricity as needed.
The developments in green hydrogen – from Japan, to the US, to the EU – are “really good news”, says Blank of the Rocky Mountain Institute. “Green hydrogen has high potential to address many of the things that keep people awake at night because the climate change problem seems unsolvable.”
This article was originally published by Yale e360, and is republished with permission – read the original story here. This is also why this story does not have an estimate for its carbon emissions, as Future Planet stories usually do.
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