The Energy & Carbon Intensity of Mining:
Understanding the Growing Importance
of Renewable Energy
Assoc. Prof. Gavin M. Mudd
RMIT University, Melbourne, Australia
… plus Mineral Policy Institute (Australia), World Mine Tailings Failures (USA)
Georgius Agricola (1556) :
“… the strongest argument of the detractors is that the fields are
devastated by mining operations … Also they argue that the woods
and groves are cut down, for there is need of an endless amount of
wood for timbers, machines, and the smelting of metals. And when
the woods and groves are felled, then are exterminated the beasts
and birds, very many of which furnish a pleasant and agreeable food
for man. Further, when the ores are washed, the water which has
been used poisons the brooks and streams, and either destroys the
fish or drives them away. Therefore the inhabitants of these regions,
on account of the devastation of their fields, woods, groves, brooks
and rivers, find great difficulty in procuring the necessaries of life …
Thus it is said, it is clear to all that there is greater detriment from
mining than the value of the metals which the mining produces.”
2Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
Presentation Overview
• Energy Use in Mining ‘101’ = Carbon Emissions
• Current ‘Mega-Trends’ in Mining
• these underpin likely energy/carbon intensity
• Life Cycle Assessments of Metal Mining
• Examples & Case Studies
• Growing Need for Renewable Energy
• Metals for Renewable Energy & Batteries
• Summary
4Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
Energy Use in Mining ‘101’
• Mining is very simple with its energy needs:
DIESEL & ELECTRICITY
• Diesel is used in haul trucks, excavators,
underground vehicles, on-site power plants
• Electricity is used in ore processing, site
administration buildings, etc.
Really, it’s that simple
• Energy also used to make machines,
chemicals, transport stuff / people, etc …
5Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
Energy Intensity in Mining
• There are many factors which can affect the
energy needed to operate a mine:
• ore body depth: deeper = more energy
• Age of a mine: older mines often deeper, longer haul
roads / shafts, sometimes more waste rock at greater
distance to dump, …
• Ore processing configuration: SX-EW v flotation,
especially comminution grind size, scale, …
• Environmental requirements: need for water treatment
(or not), tailings disposal configuration (especially if
paste / thickened tailings are used), etc …
6Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
Carbon Issues in Mining
• Carbon emissions derived mostly from direct
diesel use (Scope 1) & indirectly from
electricity (Scope 2) (minor amounts from
explosives, land use change, some chemicals)
• For electricity, carbon intensity is closely
linked to power plant type: coal, gas, diesel,
solar, geothermal, etc …
Put simply, more energy intense mines are
typically more carbon intensive
7Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
Key Global Mining MEGA-Trends
• Globally, we have plenty of mineral resources already
know to meet reasonable societal demands for
decades … primary metals, critical metals, etc.
• The real issues are how / what / where / when / why we
mine different commodities … e.g. coal v lithium
• Global mega-trends already affecting mining include:
• continually growing demand (with demand for ‘critical metals’
expected to grow substantially)
• declining ore grades … sometimes declining ore quality
• deeper deposits … variable around the world but still very real
• increasing wastes to manage: tailings & waste rock (& slags)
• growing community, investor & regulatory concerns
• gradually growing chemicals / energy / water inputs
8Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
Global Cu Mine Production by Country
9Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
0
2
4
6
8
10
12
14
16
18
1900
1910
1920
1930
1940
1950
1960
1970
1980
1990
2000
2010
An
nu
al
Co
pp
er
Pro
du
cti
on
(M
t C
u)
USA
AustraliaCanada
Chile
China
Africa
Re
st
of
the
Wo
rld
Russia-Eastern Block
Declining Ore Grades: Very Real
10Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
0
3
6
9
12
15
18
21
24
27
1770 1790 1810 1830 1850 1870 1890 1910 1930 1950 1970 1990 2010
Co
pp
er
Ore
Gra
de
(%
Cu
)
Australia Canada
PNG India
UK Poland
Indonesia Chile
Brazil USA
Laos Sweden
Note: some PNG data(1907-1970) is
greater than 30% Cu.
Ever-Growing Waste Rock Piles …
11Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
0
330
660
990
1,320
1,650
1,980
2,310
0
40
80
120
160
200
240
280
1895 1905 1915 1925 1935 1945 1955 1965 1975 1985 1995 2005
Wa
ste
Ro
ck
(G
old
, B
lac
k C
oa
l)
Wa
ste
Ro
ck
(C
u,
Dia
mo
nd
s, U
, B
row
n C
oa
l)
Copper (Mt) Uranium (Mt)
Diamonds (Mt) Brown Coal (Mm3)
Gold (Mt) Black Coal (Mm3)
(Mm3)
(Mm3)
No Obvious AMD …
BUT pH 3.5
Life Cycle Assessment of Mining
• LCA is a formal methodology to quantify the
inputs & outputs to produce a good or service
• Literature covers most metals reasonably well
• Often the key metrics focussed on are energy,
carbon, water … sometimes toxicity, land use,
but waste rarely (not sure why!)
• One tricky issue is the allocation for multi-
metal mines – typically solved by value• e.g. Cu-Au mine splits energy inputs / carbon outputs based
on respective value of each metal
12Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
Theoretical LCA Studies: Cu
13Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
0
300
600
900
1,200
1,500
0 0.5 1 1.5 2 2.5 3
En
erg
y I
nte
nsit
y (
GJ/t
Cu
)
Ore Grade (Cu/%)
Concentrate-Smelting (75 µm comminution)
Concentrate-Smelting (5 µm comminution)
Direct Smelting
Heap Leaching
Pressure Leaching
In Situ Leaching
0
30
60
90
120
150
0 0.5 1 1.5 2 2.5 3
GG
Es I
nte
nsit
y (
t C
O2e/t
Cu
)
Ore Grade (%Cu)
Concentrate-Smelting (75 µm comminution)
Concentrate-Smelting (5 µm comminution)
Direct Smelting
Heap Leaching
Pressure Leaching
In Situ Leaching
Norgate-Jahanshahi, 2010, Mins. Eng.
Theoretical LCA Studies: Rare Earths
14Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
0
50,000
100,000
150,000
200,000
250,000
300,000
350,000
400,000
450,000
0 10 20 30 40 50 60 70 80 90 100
GH
G E
mis
sio
ns
(kg
CO
2e/t
TR
EO)
Cumulative TREO Production Distribution (%)
Tanbreez ZandkopsdriftAshram (Eldor) Olympic DamChina Sichuan Mianning Strange LakeDubbo Zirconia Bayan OboFoxtrot KvanefjeldNechalacho (Thor Lake) Norra KärrTantalus Nolans BoreBrowns Range AraxáZeus (Kipawa Lake) NguallaBokan Dotson Bear LodgeSteenkampskraal BucktonChina Southern Seven Provinces (Type B) Eco RidgeRound Top China Southern Seven Provinces (Type A)Songwe Hill
Ch
ina
Ion
ic C
lay
(B)
Bayan Obo
Monazite XenotimeLujavriteIonic Clay
Allanite Apatite Bastnäsite Eudialyte
Ch
ina
Ion
ic C
lay
(A)
Kvanefjeld
Araxá
Bea
r Lo
dge
Songwe Hill
No
lan
s B
ore
Bro
wn
s R
ange
Sustainability Reporting: Real LCA Data
15Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
Source: WMC
Sustainability Reporting: Real LCA Data
16Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
Source: Anglo Platinum
Case Study: LCA of Copper Mining
17Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
y = 1.5548x-0.606
R² = 0.28
0
2
4
6
8
10
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5
GH
G I
nte
nsi
ty (
t C
O2e/
t C
u)
Ore Grade (% Cu)
Mine + Leaching, SX-EW (LSE)
Mine + Concentrator
Mine + Conc. + LSE
Mine + Conc. + Smelter
Mine + Conc. + Smelter + Refinery ± LSE
Mine + Concentrator
Case Study: LCA of Gold Mining
18Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
y = 27.92x-0.604
R² = 0.3328
y = 17.726x-0.382
R² = 0.5243
y = 7.9054x-0.516
R² = 0.4344
0
10
20
30
40
50
0 10 20 30 40 50 60
Un
it G
ree
nh
ou
se
Em
iss
ion
s (
t C
O2/k
g A
u)
Ore Grade (g/t Au)
Coal
Diesel
Gas
Hydro
Coal/Hydro
Diesel/Geothermal
Gas/Hydro
Hydro/Coal
Hydro - (0.72, 81.2)Coal - (5.3, 59.57)
Hydro -(77.1, 0.2), (82.39, 0.2)
Coal
Hydro
Diesel
Case Study: LCA of Gold Mining
19Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
0
10
20
30
40
50
60
70
0 110 220 330 440 550 660
Un
it G
ree
nh
ou
se
Em
iss
ion
s (
t C
O2/k
g A
u)
Unit Energy Consumption (GJ/kg Au)
Coal Diesel
Gas Hydro
Coal/Hydro Diesel/Geothermal
Gas/Hydro Hydro/Coal
Points excluded:(301.1, 95.01) and(288.9, 117.47)
Case Study: LCA of Nickel Mining
20Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
0
10
20
30
40
50
0 100 200 300 400 500 600 700
t C
O2e
/ t
Ni±
Cu
±C
o
GJ / t Ni±Cu±Co
Inco Sudbury Thompson
Murrin Murrin Sorowako
WMC Total Yabulu
Xstrata Canada Cerro Matoso
Laterite ProjectsSulfide Projects
0
12
24
36
48
60
72
0
1
2
3
4
5
6
1991 1993 1995 1997 1999 2001 2003 2005
En
erg
y I
nte
ns
ity (
GJ
/t N
i)
Em
iss
ion
s In
ten
sit
y (
t S
O2/t
Ni;
t C
O2/t
Ni)
Sulfur Dioxide (t SO2/t Ni)
Energy Intensity(GJ/t Ni)
Greenhouse Gases(t CO2/t Ni)
Global Nickel Mines Kalgoorlie Nickel Smelter
LCA of Mining in Papua New Guinea
21Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
0
0.5
1
1.5
2
2.5
3
1996 2000 2004 2008 2012 2016
En
erg
y I
nte
nsit
y (
GJ/t
ore
)
Ok TediMisima
Porgera
Lihir
Hidden
Valley
(a)
Simberi
0
17
34
51
68
85
102
1996 2000 2004 2008 2012 2016
Ele
ctr
ical
Inte
nsit
y (
kW
h/t
ore
)
Ok Tedi
Misima
Porgera
Hidden
Valley
(b)
Lihir
0
0.3
0.6
0.9
1.2
1.5
1.8
1996 2000 2004 2008 2012 2016D
iesel
Inte
nsit
y (
L/t
ro
ck)
Ok
Tedi
Misima
Porgera
Lihir
(c)
Hidden
Valley
0
20
40
60
80
100
120
140
1996 2000 2004 2008 2012 2016
Carb
on
In
ten
sit
y (
t C
O2/t
ore
)
Ok Tedi
Misima
Porgera
Lihir
Hidden
Valley
(a)
Simberi
0
6
12
18
24
30
36
1996 2000 2004 2008 2012 2016
Carb
on
In
ten
sit
y
Ok Tedi (t CO2/t Cu)
MisimaPorgera
Lihir
Hidden
Valley
Au mines(t CO2/kg Au)
(b)
Simberi
Growing Need for Renewable Energy
• Mining is only just beginning to explore the full
potential of renewable energy technologies as well as
shifting to electric vehicles
• Goldcorp’s enw Borden Lake Au mine is now fully
electric … a remarkable step change
• Chilean mines are building 100’s MW of solar panel
farms … in contrast Australia is minimal
• Australia’s former Kidston Au mine is now being
transformed into a solar-wind-pumped hydro project
• PNG’s Lihir mine extracts energy from geothermal
activity related to the geology of the mine … although
initially it ignored this resource
22Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
Energy …
Oz Style
Energy in Australia 2012BREE for RET
Sandfire’s Solar Farm at DeGrussa (WA)
24Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
Geothermal Energy at Lihir (PNG)
25Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
Metals for Renewable Energy & Batteries
• There is widespread concern about the ability to meet the rapidly
growing demand for metals and minerals used to make energy
storage batteries and various renewable energy technologies
• e.g. batteries need lithium, nickel, cobalt, graphite, … future V? Zn? Na?
• Renewable energy can use Te, In, Cd, Ga, … plus common metals
• There is often confused concern about resource depletion versus
concentration of supply: these are not the same thing !
• Based on known resources – we have absolutely plenty of
deposits already known to continue the roll-out of renewable
energy & batteries to meet current climate targets (e.g. Paris
Agreement) or even more ambitious targets
• There remain real issues of supply concentration, as well as
resource concentration … but these can be addressed in
numerous ways by governments, industry and community
26Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
Summary: Energy & Carbon vs Mining
• The energy & carbon intensity of mining will continue
to grow … often despite efforts to be more efficient or
deploy new technology
• declining ore grades are crucial in this regard
• Critical to understand the energy-carbon drivers for
each mine site – every mine can be quite different
(sometimes surprisingly so)
• Growing reliability of sustainability reporting is
providing extensive data which can be used to
understand energy-carbon intensity of mining
• Mining is crucial to supply the metals required for
renewable energy & energy storage batteries
27Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019
Acknowledgements
• UBA for supporting my participation
• Peter Diehl (WISE Uranium Project)
• Special thanks to former PhD students Zhehan Weng, Stephen
Northey, Tim Werner
• Funding support from CSIRO over the years
• The many communities I’ve visited who live with mines (& their
companies & governments) in all sorts of creative ways !
28Mudd: Energy & Climate Issues in Mining UBA Raw Materials & Environment Conf, Feb. 2019