Proton exchange membrane (PEM) fuel cells, which use platinum catalysts, are the consensus fuel cells of choice for road transport because of their low operating temperatures, high efficiencies, light weight and small volume.
These modular fuel cells can be stacked in series to create higher power output, emit zero greenhouse gases (GHGs) and enjoy the high energy density that hydrogen provides.
Fuel cell electric vehicles (FCEVs) using PEM fuel cells can refuel in three to five minutes.
They provide consistent power output until the hydrogen fuel runs out and FCEVs are best suited initially to applications where there is a demanding duty cycle that requires prolonged energy output and high asset use in a zero-emission environment.
Virtually every automotive manufacturer in the world is considering FCEVs in the knowledge that everything that transports goods over long distance will have to be fuel-cell driven to meet global decarbonisation yardsticks.
National governments, notably those of China, Japan and Korea, are positioning themselves four-square behind hydrogen fuel cell travel and private-sector venture capital companies are investing in the new technology.
One of these is a venture capital fund called AP Ventures, which has major cornerstone investors in Anglo American Platinum, the Public Investment Corporation of South Africa, Mitsubishi Corporation of Japan and the SPARX Mirai Fund, which includes Toyota Motor Corporation and Sumitomo Mitsui Banking Corporation.
Led by Andrew Hinkly and Kevin Eggers, AP Ventures invests in the hydrogen value chain, fuel cell electric mobility and energy storage markets.
In response to questions put by Mining Weekly for this fuel cell feature, AP Ventures provided statistics to show that the number of FCEV buses, trains, medium-size cars and forklifts has risen significantly.
In China, more than 400 000 FCEV buses are on the roads. In the US, 15 000 out of a total global count of 20 000-plus forklift trucks are using FCEV technology. In California, 7 800 mainly Toyota, Honda and Hyundai FCEV cars have access to 40 hydrogen filling stations, with 200 more planned. California’s filling stations obtain their hydrogen from electrolysers that, like FCEVs, also can use platinum group metal (PGM) catalysts.
In South Africa, PGM mining company Impala Platinum has been putting a showpiece FCEV forklift truck through its paces successfully at its refinery in Springs, where an economically viable hydrogen refuelling station has been established.
Pricewise, FCEV technology is following the same trajectory as solar energy, which was initially very high, but then quickly fell to competitive levels through economies of scale.
Interestingly, the Fraunhofer Institute for Solar Energy Systems calculates that FCEVs are more GHG-emissions friendly than battery electric vehicles.
Fuel cells are also making inroads into the stationary electricity generation market.
The stationary power fuel cell systems deployed last year used bottled hydrogen, ammonia and methanol as fuel and can operate for extended periods in –40 ºC to 50 ºC environments without the need for cooling.
South Africa’s largest mobile communications company, Vodacom, has installed more than 300 stationary fuel cell backup power generators at telecommunication base stations and plans to install another 250.
Mining company Anglo American provided minigrid electricity for 34 rural South African households in 2014 using three 5 kW methanol fuel cells, a 14 m3 methanol tank and a 73 kWh battery bank. Technology advances later led to stationary fuel cells providing 500 households with electricity and water in South Africa’s KwaZulu-Natal province. A fuel cell system has also been installed at a clinic in South Africa’s Gauteng province to provide uninterrupted electricity for medicine and vaccine fridges.
In the US, 40 states use 235 MW of fuel cell backup power at telecommunications, government, railway and utility sites; larger 5 MW stationary power fuel cells are backing up data centres, banks and hospitals; and fuel cells are continuously on standby to provide power when emergencies arise, as was the case in 2012 when they provided power for hundreds of hours after Hurricane Sandy struck the US and the Bahamas.
The Hydrogen Economy
The fuel cell deployment projection by the Hydrogen Council, a global CEO-level energy initiative, shows hydrogen providing power generation, transport and heat across a broad front that also covers heavy industry. As a low-carbon energy source, hydrogen fuel cell technology is replacing existing technologies that have higher carbon emissions.
As hydrogen does not aggregate in pure form, it has to be produced from natural gas, coal or water, and its mitigation of climate change thus depends on the carbon content of the energy required to produce it.
The ideal is hydrogen with zero GHG baggage, which is why platinum-catalysed electrolyser processing, powered by solar or wind energy, is putting up its hand as the technology of choice and the sole route to carbonless, ‘green’ hydrogen production.
But, in reality, it is steam methane reforming (SMR) and coal gasification that are the most common hydrogen production routes, with natural gas and steam forming ‘grey’ hydrogen, which has carbon dioxide (CO2) as a polluting by-product.
If the offending CO2 by-product is captured and stored, or repurposed in different applications, SMR and coal gasification can move up an environmental notch to a less carbon-tainted hydrogen, referred to as ‘blue’ hydrogen. If nothing is done, it is labelled as ‘grey’ hydrogen, which can be produced at a low price. But that price hinges on the price of natural gas, with €1.50/kg an outcome if the price of natural gas remains low.
However, a rise in the natural gas price and the imposition of carbon pricing would lower the competitiveness of grey hydrogen.
A critical determinant of the price of green hydrogen is the price of the green electricity used by electrolysers. Currently, green hydrogen costs between €3.50/kg and €5/kg, but consulting firm McKinsey is among those that expect this cost to be lowered significantly over the next decade as a result of more efficient catalysis, as well as scaled-up electrolyser capacity.
Last year, 20 MW of electrolyser capacity was commissioned and, since then, projects of up to 100 MW have been announced. There is a particularly large potential for electrolyser hydrogen production from countries such as South Africa and Australia, which have abundant solar and wind power potential. Although the cost of renewable power has fallen steeply, improved technology, added capacity and more effective energy storage are poised to lower these costs still further and expand investment in green hydrogen.
Lower hydrogen transport and storage costs are targeted to widen hydrogen’s adoption.
AP Ventures has, therefore, invested in United Hydrogen, of the US, and Hydrogenious, of Germany.
United Hydrogen purifies and distributes by-product hydrogen into the industrial market in the eastern US and Hydrogenious has developed liquid organic hydrogen carrier (LOHC) technologies to facilitate the efficient transport of hydrogen in liquid form. LOHC technologies use oillike carrier molecules that attach the hydrogen during storage and transport and detach from it at the desired location. The reusable carrier molecules, which operate at ambient temperatures, have a high 57 kg/m3 hydrogen storage capacity.
There is also the possibility of decentralised hydrogen production, which has the potential to eliminate storage and transport costs. Ergosup, another company in which AP Ventures is invested, has developed electrolysis technology for distributed, high-pressure green hydrogen for initial deployment in the drone, forklift truck and laboratory markets.
Ergosup has cut electrolysis costs using nonspeciality materials in its electrolyser solution to produce decentralised green hydrogen from a unit that also has storage and compression capabilities.
“We’re very optimistic about the role that fuel cells and hydrogen will play in decarbonising key sectors of the economy. Hydrogen and fuel cells are well established in many industrial applications, such as energy storage and mobility, and are fast-growing and developing technologies. We believe they have the potential to provide an attractive financial return and have a very tangible impact on developed and developing economies.
“We’re seeing a marked expansion of the number of enquiries about opportunities to invest in novel hydrogen technologies and there is progressively more interest from governments around the role of hydrogen,” AP Ventures told Mining Weekly.
Among the strengths of fuel cells and the hydrogen economy is that many of the metals and materials used in hydrogen technologies, or which allow for both current and future use, are already available and have established supply chains with relatively stable prices.
For example, the PGMs that are critical in many fuel cell and electrolyser technologies have an established mining infrastructure, market and supply chain in place that can robustly support demand. This is in stark contrast to other low-carbon technologies, such as lithium-ion batteries, where new mining and refining infrastructure has to be developed to meet demand.
This is challenging for an industry to achieve and carries substantial price volatility risk. There are also limited recycling options for battery metals, and those that are in operation are highly polluting.
By contrast, PGMs have been used in automotive catalytic converters for many years, and are now being repurposed into fuel cell applications using metals that are highly recyclable.
The opportunity created by the heightened demand for a cleaner environment, reduced CO2 and acceleration towards a sustainable energy future needs to be seized with greater firmness by South Africa as the host of the world’s biggest PGMs endowment.