COULD BIOMASS BE A
SOLUTION?
Debates concerning the implementation of carbon neutral
sources of energy continue to make headlines. Great strides
have been made in Africa’s development of biomass.
Africa has the highest portion of bioenergy, at 45% of the total
energy mix, thereby validating the continent’s potential to
capitalise on this renewable energy source. Furthermore, there
are currently industrial scale biomass and waste-to-energy
plants being explored in Angola, Tanzania, Cote D’Ivoire, Kenya,
Malawi, Mauritius, Nigeria and Ethiopia.
Within a global context, using GE’s renewable steam technology,
the Kamisu Biomass Power Generation plant in Japan will run
on 100% biomass to generate 50 megawatts (MW) of reliable
energy. According to GE, this is one example of how the
company is adapting its technologies to meet market demand
to support more renewable fuel sources like biomass.
Lee Dawes, GE Steam Power Sub-Saharan Africa CEO says the
South African context will be different. While biomass and
waste to energy are considered in the latest IRP, there has
been no clear determination on how it will be implemented.
“A consideration to reduce CO 2 emission could be a coal
to biomass conversion. Depending on the size of a plant,
typically, existing power plants can be adapted to utilise a
wide range of biomass fuels up to 20% to supplement or
displace coal providing additional benefit to reduce CO 2 , NOx
and Sox”.
MINING FOR RENEWABLES
Last year mining companies have adopted solar and wind power
to reduce their energy cost and carbon footprint in a rather
lengthy process. Successful flagship projects have removed
concerns about production loss and independent power
producers (IPPs) have started financing solar and wind plants at
remote mining sites; IPPs sell electricity to miners on a power
purchase agreement (PPA) basis.
To mining companies, the PPA-cash flow is similar to what
they are used to from diesel contracts – but it comes with cost
reductions. IPPs are highly specialised in electricity generation,
they are also looking at other solutions for cost reduction. It is
no surprise that diesel genset efficiency optimisation have also
sparked interest. Diesel engines only convert 40% of the fuel
energy into electricity, while the rest is not used. Waste heat
recovery can reduce diesel consumption by approximately 7%.
The report, System Optimisation of Renewable Energy Microgrids
with Heat-recovery in Remote Mining shows that heat recovery
can also go hand-in-hand with renewable energy approaches
for diesel reduction. In a time when cost optimisation and
carbon mitigation are gaining importance, the question is not
which of the two solutions to choose. The answer is to combine
the two solutions together.
The Dutch manufacturer Triogen has developed a containerised
‘e-box’, a solution that is tailor-made for remote mine sites.
It has been designed for easily upgrading any diesel genset
without changing its operations and thus without affecting
maintenance or warranty requirements. The solution is based
on the conventional steam turbine technology, yet is fully
automated, compact and simple to install. Two standard 20-
foot shipping containers are connected to the exhaust gas
stack of diesel gensets and the e-box generates electricity
from the waste heat. The electricity is fed into the local grid,
so that diesel gensets do not need to produce this power and
subsequently consume less fuel.
For more information, please download the report: https://www.
th-energy.net/english/platform-renewable-energy-and-mining/
reports-and-white-papers/
MARATHON COMMITTED TO
GAS HUB
American oil company Marathon Oil has reiterated its
commitment to Equatorial Guinea and towards the
development of the country’s gas mega hub. Marathon is
one of the biggest energy investors in Equatorial Guinea,
has pledged to increase its investment in the required
infrastructure to support the Equatorial Guinean government’s
vision for the gas mega hub and the year of investment
initiative following a meeting with the president Teodoro
Obiang Nguema Mbasogo.
The company says it will continue unlocking funds to promote
the delivery of gas from neighbouring countries and cross-
border fields to maximise existing facilities and possibly consider
a second LNG train. Marathon also declared support for the
Ministry’s efforts to construct a modular refinery in Punta Europa
by undertaking a conceptual study on the Ministry’s behalf.
Marathon continues to prioritise the ongoing Alen backfill
project currently under implementation with Noble Energy,
Glencore, Atlas and Gunvor. Efforts are underway to accelerate
gas for delivery by year end 2020, while currently scheduled
for first quarter 2021. The project is an important step towards
replacing declining output from the Alba field.
The approach is based on conventional steam turbine
technology, but advances have allowed this to be deployed at
a smaller scale. It is already proven in applications like biogas
engine heat recovery, biomass combustion, industrial waste
heat, and geothermal heat. DRC IN DEAL TO PROVIDE
ELECTRICITY
“Waste heat recovery is the low hanging fruit in the diesel
reduction game,” says Dr. Thomas Hillig, managing director
of THEnergy, a Germany-based management consultancy
specializing in cleantech innovations. “Renewables have recently
opened the door for new approaches because they have
increased the acceptance of more capital-intensive solutions in
the mining industry.” At the UK-Africa Investment Summit in London, Bboxx, a
British company that produces, distributes and finances
solar-powered systems in developing countries, signed
a memorandum of understanding with the Democratic
Republic of the Congo (DRC) to provide electricity to 10
million people in the country – equivalent to 10% of the
population. The agreement intends to provide affordable,
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African Mining April 2020
www. africanmining.co.za