Sustainability Report - Antofagasta PLC

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Antofagasta plc Sustainability Report 2011
The mining companies are exploring a number of options to increase the
proportion of energy generated from alternative and renewable sources. Using
its geographic location on a mountain slope to its advantage, Los Pelambres
already generates around 10% (118,864,000 KWh), of its total energy
consumption from the braking of mineral conveyor belts.
At El Tesoro, we are completing the construction of a solar energy plant that
will reduce El Tesoro’s CO 2 emissions by 4% by the end of 2012. Heat from
the solar energy plant will replace 55% of the diesel used in the site’s boilers
for the electro-winning process. In 2012 we plan to pilot a photovoltaic solar
concentration plant with the same technology used in El Tesoro.
Antofagasta Minerals is investing in a 115MW wind farm project near Los
Pelambres which will provide approximately 20% of the site’s energy
requirements and will be operating in 2014. Energía Andina S.A, a joint
venture between Antofagasta Minerals and Origin Energy Australia, is focused
on the exploration and development of geothermal energy prospects in Chile.
It has been granted 15 concessions to date and eight projects are in the
exploration phase, each with potential capacity of 100 - 200MW. In 2012 the
company will conduct feasibility studies to assess the viability of the projects. If
successful, drilling of geothermal production wells will begin in 2013 and
Energía Andina could be producing energy by 2016.
Mulpun Energy, a joint venture between Antofagasta Minerals and Carbon
Energy Limited of Australia, continues to work on its underground coal
gasification (UCG) project near Valdivia in southern Chile. This technology
transforms coal into synthetic gas that can be used to generate electricity with
a lower emission factor. In August 2010 the division received environmental
approval for the first stage of the project, which allows construction and
operation of a pilot scheme, including the first UCG panel and on-site facilities,
and engineering studies in relation to the trial project were undertaken in the
second half of the year.
Fuel efficiency
Fuel is used for transporting and moving material extracted from mines and
represents a significant portion of production costs. Mine size and layout and
the size of trucks used on the site are some of the factors affecting fuel
efficiency. In 2011, Los Pelambres made some changes to its mining plan that
reduced the distances covered by trucks at the site, improving its fuel
efficiency from 0.43 litres per tonne (2010) to 0.33 (2011). Michilla is relatively
less fuel efficient because it requires smaller trucks operating over a large
distance, and as the pit grows deeper over time, the distance travelled by
trucks increases. The reduction in fuel use at Michilla was due to the
temporary suspension of part of its operations during the year.
Fuel efficiency (Litres of fuel per tonne of material moved)
Los Pelambres
Esperanza
El Tesoro
Michilla
n/a: not available
2011
0.33
0.35
0.32
0.55
2010
0.43
n/a
0.33
0.60
2009
0.43
n/a
0.37
0.55