A Case for Hydrogen to Decarbonize Mining
Connor Dolan
By Quailan Homann
The mining and materials extraction industry has traditionally been a sector that is difficult to decarbonize. Mines commonly utilize polluting diesel engines to power backup generators, underground loaders, large material handling trucks, and other vehicles. To effectively combat the climate crisis, protect the health and safety of the workers, and to improve the carbon footprint of existing solutions, some mining companies are taking steps to adopt zero-emission technologies such as fuel cells.
Mining companies and other stakeholders have expressed interest in transitioning to hydrogen fuel cells as both an economic and environmental solution.
According to a viability analysis by C. Funez Guerra from the National Hydrogen Centre in Spain, the use of hydrogen as a fuel for underground mining is profitable under present conditions. This is exceptional news for companies concerned with the cost of fuel cell technology and shows that adopting hydrogen is not just good for the environment, but also makes financial sense.
To demonstrate the use of fuel cells in mining applications, platinum mining company and FCHEA member Anglo American, in partnership with gas company ENGIE, is retrofitting an ultra-heavy-duty mining truck with 800 kilowatts (kW) worth of Ballard Power Systems’ fuel cell stacks for use in the company’s South African platinum mines. Other industry partners are assisting in the realization of the project. FCHEA members Plug Power and Nel Hydrogen are developing a full custom compression, storage, and dispensing system and supplying a 3.5-megawatt electrolyzer for on-site renewable hydrogen production, respectively. The complete fuel cell trucking system is furthering Anglo American’s end goal: to build a zero-emission mine.
Anglo American ultra-heavy-duty mining truck to be retrofitted with 800 kW of fuel cell modules. Source: Ballard Power Systems
A clean source of energy with equal performance
Fuel cells use an electrochemical reaction between ambient oxygen and hydrogen fuel to produce electricity with water vapor and heat as the only emissions. When hydrogen is sourced from renewable energy using a water-splitting method called electrolysis, the resulting fuel and processes are completely renewable. Due to the chemistry of fuel cells, they can reach efficiencies as high as 60 percent. Fuel cells are already proving their strength and benefits as an electric drivetrain in a variety of transportation applications, including heavy-duty long-haul and drayage trucks, material handling vehicles, light-duty passenger cars, boats, and trains.
An analysis by the Rocky Mountain Institute concluded that fuel cells can generate comparable power to standard mining diesel engines without burdening the system with extra weight. By matching the requirements of current engines, fuel cells are a proven substitute with the added benefit of eliminating carbon emissions that contribute to global warming.
Health and safety improvements
Removing diesel engines does more than reduce carbon emissions. In addition to carbon dioxide, the combustion of diesel emits carbon monoxide, NOX, and particulate matter. The American Cancer Society has identified diesel exhaust as a carcinogen as well as a contributor to lung and heart diseases. Exhaust conditions are exacerbated in the enclosed space of an underground mine, forcing companies to invest heavily into outfitting mines with proper ventilation. According to Kim Trapani, a ventilation engineer at Stantec, ventilation contributes to between 30 and 40 percent of a mine’s total energy operating costs. Trapani states by moving to electric-drive machinery, companies can improve conditions for workers and reduce ventilation requirements up to 50 percent. The only emissions produced from fuel cells are heat and water vapor, making them an ideal candidate for mines. Dr. Patrick Hartley, Director of Oil Gas & Fuels at the Australian Commonwealth Scientific and Industrial Research Organisation, echoed this sentiment, stating that hydrogen fuel cells have applications to displace diesel in mines for safety reasons.
Fuel cell advantage
Due to the power density of current battery technology, scaling systems to meet the power demands of large mining equipment would be burdensome due to the size and weight. In contrast, fuel cells are more easily scalable, providing adequate power without weighing down the mining vehicles. In addition, fuel cell-powered vehicles have a much longer range and dramatically reduced refuel time, more in line with traditional combustion vehicles than their zero-emission battery counterparts. The advantages of fuel cells are currently being recognized in a smaller material handling applications, via forklifts; the only need is to scale up the stacks for mining purposes.
Conclusion
Tackling the climate crisis calls for deep decarbonization across all sectors. Within the mining industry, hydrogen and fuel cell technology offers a robust solution to replace diesel engines with a zero-emission solution that helps improve the environment and worker safety, while supporting a company’s bottom line.