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green mining
The methane flaring point at Sibanye Gold’s Beatrix mine (photo: Sibanye Gold).
points out that it is common cause that fuel cells have
zero emissions. Should the fuel cell-powered equip-
ment prove feasible, it will replace the acid lead bat-
teries currently used to power underground locomo-
tives in Anglo American mines. Such replacement
will do away with the issues of lead recycling and
disposal of environment-unfriendly battery acid.
“Both the loco and the mini-dozer have hybrid
systems comprising lithium ion batteries and fuel
cells. With the loco, we will do away with the need
to charge the acid lead battery for eight hours at the
end of a shift and will charge the lithium ion battery
through the fuel cell in little over half an hour. Pro-
ductivity will be substantially enhanced.
“With a dual system, both the loco and mini-dozer
will be powered by the fuel cell when undertaking
light work but they will draw from the lithium ion
battery when peak power is required.”
He says that the development of the business case
for the fuel cell locos and mini-dozers includes ele-
ments such as developing a total cost of ownership
model that can be compared to alternatives, and eval-
uating emissions and safety advantages.
“Underground testing is critical because the degra-
dation of the fuel cell stack needs to be established in
the challenging underground environment. We need
to track performance over a period in order to estab-
lish comparative data against the performance of lead
batteries (in the case of the loco), which last between
18 months and three years depending on the nature of
the underground environment.
“Another challenge is the supply and logistics of
providing hydrogen to underground locations,” says
Joseph. “We are working with Air Products on devel-
oping hydrogen infrastructure solutions for under-
ground testing.
“Attention is also being paid to developing operat-
ing procedures in conjunction with health and safety
experts to ensure that underground operation will
comply with all relevant regulations. We have com-
pleted all the necessary risk assessments in order
to get approval from the Department of Mineral Re-
sources for the supply of hydrogen to underground
locations.”
Joseph says that should the business cases prove
feasible, identification of partners for local assembly
and sourcing will be initiated.
With the fuel cell locos, the main focus of surface
testing currently underway at Trident SA in Germis-
ton revolves around ensuring that performance met-
rics meet underground requirements. The loco has
performed exceptionally well above ground.
“The project team is getting up to speed on oper-
ating processes such as re-fuelling, discharging the
fuel tank and learning the control mechanisms. At-
tention is also being paid to maintenance processes,
including evaluating the design of the casing for the
fuel cell power system in order to establish ease of
access for maintenance. The team is also working on
understanding the design and assembly of the fuel
cell power system. In addition, comprehensive risk
assessments and development of standard operating
procedures are being undertaken,” he says.
“If the growth of fuel cell technology in under-
ground applications grows beyond a certain point,
the introduction of on-site production – possibly
powered by solar photo voltaic panels – could be con-
sidered. The ultimate dream, given current economic
and other challenges, is to look at the replacement
of diesel fleets with fuel cell-powered alternatives in
decline mines.”
The dual feed cell stacks used in the power sys-
tems of both the loco and mini-dozer are being sup-
plied by Ballard Power Systems. In partnership with
Ballard, Amplats is funding the development of a
methanol-based fuel cell home generator for rural,
off-grid usage.
Ballard said in a statement published in June after
the Hydrogen + Fuel Cells 2013 International Con-
ference and Exhibition in Vancouver that platinum-
based fuel cells provide a significant economic and
environmental development opportunity for South
