BENCHMARKING THE ENERGY CONSUMPTION OF
CANADIAN OPEN-PIT MINES
PREPARED FOR MINING ASSOCIATION OF CANADA
AND NATURAL RESOURCES CANADA
1939B_OEE_OpenPit-c4 4/1/05 3:14 PM Page 3
Library and Archives Canada Cataloguing in Publication
Main entry under title :
Benchmarking the energy consumption of Canadian open-pit mines
Issued also in French under title: Analyse comparative de la consommation d’énergie des mines à ciel ouvert du Canada.
ISBN 0-662-39538-7 Cat. No. M144-70/2005E
1. Strip mining – Energy consumption – Canada.2. Strip mining – Energy conservation – Canada.3. Energy consumption – Canada.4. Energy conservation – Canada.5. Energy auditing – Canada.I. Canadian Industry Program for Energy Conservation.
II. Mining Association of Canada.
TN291.B46 2005 622’.292’0682 C2005-980101-8
© Her Majesty the Queen in Right of Canada, 2005
For more information or to receive additional copies of this publication, write to:
Canadian Industry Program for Energy Conservationc/o Natural Resources Canada580 Booth Street, 18th FloorOttawa ON K1A 0E4
Tel.: (613) 995-6839Fax: (613) 992-3161E-mail: [email protected] Site: oee.nrcan.gc.ca/cipec
Or
Mining Association of Canada350 Sparks St. Suite 1105Ottawa ON K1R 7S8
Tel: (613) 233-9391Fax: (613) 233-8897 Web Site: www.mining.ca
Recycled paper
1939B_OEE_OpenPit-c4 4/1/05 3:14 PM Page 4
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
FOREWORD
IFOREWORD
On behalf of the Mining Sector Task Force of the Canadian Industry Program for EnergyConservation (CIPEC), the Mining Association of Canada (MAC) retained CorporateRenaissance Group to work with mining companies to establish energy benchmarks foropen-pit mines. Companies that participated in this project paid for the on-site services of the consultancy and have received individualized reports on the findings.
CIPEC consists of 26 task forces, representing the various industrial sectors in Canada, and is a partnership of industrial associations and the Government of Canada, representedby Natural Resources Canada’s Office of Energy Efficiency. The Mining Sector Task Forcecomprises members of MAC’s Energy Committee. CIPEC task forces act as focal pointsfor identifying energy efficiency potential and improvement opportunities, establishing sectorenergy efficiency targets, reviewing and addressing barriers, and developing and implementingstrategies to meet the targets.
This publication is one of a series of MAC publications demonstrating the mining industry’scommitment to energy conservation and the reduction of greenhouse gas emissions – acommitment essential to our common well-being. Among our members, good energypractices are simply accepted as being good business practices.
TABLE OF CONTENTS
III
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
TABLE OF CONTENTS
1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21.2 Focus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21.3 Layout of Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. METHODOLOGY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52.1 Boundaries of the Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1.1 Gold and Iron Ore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62.1.2 Oil Sands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2 The Mining Association of Canada (MAC) Sample . . . . . . . . . . . . . . . . . . . . . . 72.2.1 Analysis: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72.2.2 Comparative Energy Costs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92.2.3 Analysis: Open-Pit Mining Operations . . . . . . . . . . . . . . . . . . . . . . . . . 92.2.4 Analysis: Milling Operations – Gold Recovery . . . . . . . . . . . . . . . . . . . 102.2.5 Analysis: Concentrator Operations – Iron Ore . . . . . . . . . . . . . . . . . . . 122.2.6 General and Administrative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3. RESULTS: BENCHMARKING PARTICIPATING MINES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133.1 Comparative Unit Costs for Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153.2 Inter-Mine Comparative Energy Costs – Total Operations . . . . . . . . . . . . . . . 173.3 Inter-Mine Comparative Energy Costs – Mining Operations . . . . . . . . . . . . . . 21
3.3.1 Total Mining Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213.3.2 Waste Rock Operations – Stages of Production . . . . . . . . . . . . . . . . . . 233.3.3 Ore Mining Operations – Stages of Production . . . . . . . . . . . . . . . . . . 283.3.4 Comparisons Based on Total Material Removed . . . . . . . . . . . . . . . . . 34
3.4 Inter-Mine Comparative Energy Costs – Mill/Concentrator Operations . . . . . 433.4.1 Total Mill/Concentrator Operations . . . . . . . . . . . . . . . . . . . . . . . . . 433.4.2 Mill/Concentrator Operations – Stages of Production . . . . . . . . . . . . . 45
3.5 General and Administrative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
4. POTENTIAL SAVINGS: ACHIEVING BENCHMARK STANDARDS . . . . . . . . . . . . . . . . . . . . . . . 534.1 Context . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 544.2 Potential Energy Savings: Mining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 554.3 Potential Energy Savings: Milling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Leading Canadian to Energy Efficiency at Home, at Work and on the Road
The Office of Energy Efficiency of Natural Resources Canadastrenghens and expands Canada’s commitment to energy efficiency
in order to help address the challenges of climate change.
INTRODUCTION1
2
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
1 INTRODUCTION
1. INTRODUCTION
1.1 Background
Energy costs represent a significant component of the total costs of operations for Canada’smining sector. Directly and indirectly, the energy use in the mining sector is also a significantcontributor to Canada’s greenhouse gas emissions. Improving energy efficiency reducesgreenhouse gas emissions that contribute to climate changes. There are, therefore, compellingeconomic and environmental reasons for mining and milling operations to examine theirenergy consumption comprehensively.
The Mining Association of Canada (MAC) has sponsored this energy benchmarking project.The focus is a detailed comparison of the energy consumption for open-pit mining andconcentration activities. The Office of Energy Efficiency of Natural Resources Canada(NRCan) has provided assistance for this study, which is a part of NRCan’s ongoing effortsto promote more efficient energy use in Canada.
1.2 Focus
The focus of this analysis is the mining and concentration operations of open-pit mines ofMAC members. Nine mining/milling operations participated in the project, and the samplespecifically included the operations of gold, oil sands and iron ore establishments.
The project involved a detailed inter-facility comparison of the energy consumed in mining(drilling – transport) and concentration (crushing – tailings disposal). Approximately 25 categories of energy cost and usage information were examined.
Given the significantly different nature of the milling/concentrator operations for gold and iron ore operations, energy comparisons for these aspects of the operations have beenaggregated into larger groupings where feasible. The oil sands operations are comparedonly with regard to their mining activities.
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
INTRODUCTION 1
31.3 Layout of Report
We begin by outlining our methodology in Section 2. We describe our approach fordeveloping energy cost comparisons ($/kilotonne mined; $/kilotonne milled) to analysethe operations of the study participants.
Section 3 presents the results of the detailed benchmarking of energy costs and usage forthe nine participating establishments. Inter-establishment comparisons are presented at themine and mill levels, as well as at the various stages of production.
Section 4 presents results on the potential savings generated by achieving benchmark standards. Comparing the costs for each participant with those for the lowest-cost operationsproduces the estimated potential savings.
METHODOLOGY2
6
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
2 METHODOLOGY
2. METHODOLOGY
2.1 Boundaries of the Analysis
The focus of the analysis of comparative energy costs and usage was as follows:
2.1.1 Gold and Iron Ore
The gold and iron ore energy analysis focused on mining and milling/concentration operations.
2.1.2 Oil Sands
The oil sands energy analysis focused on the mining operations.
FOCUS OF ANALYSIS
Ongoing Exploration
Mining Concentration
Smelting,Refining, Etc.
FOCUS OF ANALYSIS
Overburden Removal
Mining HydroTransport
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
METHODOLOGY 2
72.2 The Mining Association of Canada (MAC) Sample
A total of nine establishments participated in this project. Each case study included anopen-pit mining facility. For seven of the nine mines, energy information was provided formilling/concentrator operations. These included four gold recovery operations producinggold bars and three iron ore operations producing concentrates.
2.2.1 Analysis: Overview
The objective of the analysis is to provide a detailed inter-facility comparison of the costper kilotonne mined and processed, split into costs per unit of energy and energy consumedper kilotonne for the following:
Open-Pit Mining
Nine mining operations will be compared – all operations, including the transport of oreto the crusher.
Milling/Concentrator Operations (Gold Recovery and Iron Ore Concentration)
The analysis will reflect comparisons of energy consumption and costs for the four goldrecovery facilities and three iron ore facilities and will include crushing, grinding and theaggregate of all production stages beyond grinding to loadout, plus process water, tailingsdisposal and support services.
A more detailed process comparison would not be meaningful due to the radically differentprocesses followed by the companies. However, a more detailed analysis of each company’smilling/concentrator processes was presented to the individual companies involved in thestudy.
In all cases, energy consumption will be based on kilowatt hour equivalents (kWhe). Theconversion factors for other categories of energy are illustrated below. These conversionsare derived from energy content factors reported in Canada’s Energy Outlook 1996–2000,Natural Resources Canada, April 1997, page D-3.
Open-Pit Operations (9 facilities)
Mill/Contractor Operations
Gold Recovery (4 facilities) Iron Ore (3 facilities)
8
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
2 METHODOLOGY
Table 2.1 – Conversion Factors (kWhe)
Energy Units kWhe/Unit
Diesel L 10.74
Gasoline L 9.63
Natural Gas m3 10.31
Explosives kg 1.06
Light Fuel Oil L 10.40
Bunker C Oil L 11.59
The inter-facility comparisons are based on the following unit costs and disaggregationinto components for open-pit mining and milling/concentrator facilities.
Open-Pit Mining (Gold, Iron Ore and Oil Sands)
Milling/Concentrator (Gold and Iron Ore)
Total Complex
For the total complexes, the unit energy costs and consumption will be based on a roll-upof the above. Given that some milling/concentrator operations process ore from morethan one open pit and that certain operations use different processes for different qualities/types of ore, the data for the total complex is based on:
a. the average mining energy costs and usage for the facility in the study; and
b. actual costs and usage for the energy used in milling/concentrator operations.
Given the above assumptions, the total energy costs can be subdivided to calculate the costper kilotonne milled for both gold and iron ore.
= Xkilotonne ore mined
$
kWhe
$kilotonne ore mined
kWhe[ [ [ [ [ [= Xkilotonne
ore milled
Note: One kilotonne = 2.204623 million pounds
$
kWhe
$kilotonne ore milled
kWhe[ [ [ [ [ [
NOTE: ONE KILOTONNE = 2.204623 MILLION POUNDS
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
METHODOLOGY 2
92.2.2 Comparative Energy Costs
Not surprisingly, average energy unit costs by source vary among the nine open-pit mines.
Energy source (e.g. electricity)
2.2.3 Analysis: Open-Pit Mining Operations
The open-pit mining operations were subdivided into 10 stages of production and threesupport activities. These categories are illustrated below.
1 9
$/kWh
Drilling
Blasting
Excavating
Transportation
Waste Rock Disposal
Waste Rock Removal
Stages of Production
Drilling
Blasting
Excavating
Ore Transport
Pit Dewatering
Ore Extraction
Support Activities
Road Maintenance
Service Equipment
Mine Support Equipment
10
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
2 METHODOLOGY
The total energy costs for open-pit mining operations for the nine operations were compared.
These energy costs were, in turn, subdivided into two components: $/kWhe and kWhe/kilotonne of ore mined.
Similarly, energy costs and consumption were compared for each of the nine operations bystage of production.
2.2.4 Analysis: Milling Operations – Gold Recovery
The gold recovery milling operations were subdivided into the following stages of productionand support activities.
1 9
$/kilotonne ore mined
1 9
1 9
$/kWhe
kWhe /kilotonne ore mined
Crushing
Grinding
Additional Processing of Milled Ore
Stages of Production
Support Activities
Process Water
Tailings Disposal
Plant Services
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
METHODOLOGY 2
11The total energy costs for the milling process in the four gold recovery operations werecompared.
These energy costs were, in turn, subdivided into two components: $/kWheand kWhe/kilotonne ore milled.
The total energy costs were compared for each of the milling gold recovery productionstages (crushing, grinding and additional processing through to tailings treatment and disposal). In each case, the total energy costs/kilotonne milled, $/kWhe and kWhe/kilotonnemilled were compared as illustrated above for the mining operations.
1 4
$/kilotonne milled
1 4
1 4
$/kWhe
kWhe/kilotonne milled
12
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
2 METHODOLOGY
2.2.5 Analysis: Concentrator Operations – Iron Ore
The iron ore concentration facilities were subdivided into the following stages of productionand support facilities.
* NOTE: STUDY PARTICIPANTS FOLLOWED MATERIALLY DIFFERENT PROCESSES FOR PRODUCTION STAGES RELATED TO SEPARATION,FILTRATION AND DRYING. TO ACHIEVE MEANINGFUL COMPARISONS OF ENERGY CONSUMPTION FOR THESE STAGES, IT WAS
NECESSARY TO AGGREGATE THE DATA UNDER THE HEADING “ADDITIONAL PROCESSING” EVEN THOUGH ENERGY CONSUMPTION
FOR THESE STAGES WAS REPORTED TO THE INDIVIDUAL COMPANIES.
As in the case of the gold operations, the total energy costs per kilotonne for the threeconcentrator operations were compared. These energy costs were, in turn, divided intotheir two subcomponents: $/kWhe and kWhe/tonne processed.
The above comparisons were made for each stage of production in the concentrationprocess: crushing, grinding and separation through to tailings treatment and disposal.
2.2.6 General and Administrative
The costs for general and administrative activities were compared separately for both goldand iron ore mining. As in the case of the mining and milling/concentrator analysis, thetotal energy cost for general and administrative activities per kilotonne mined was deter-mined. This number, in turn, was broken down into its cost per kilowatt hour equivalentand the kilowatt hour equivalent per kilotonne mined.
Crushing
Grinding
Separation
Filtration
Drying
Loadout
Stages of Production
Support Activities
Tailings Treatment
Process Water
Plant Services
Addi
tiona
l Pro
cess
ing
*
RESULTS: BENCHMARKING
PARTICIPATING MINES3
14
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
3. RESULTS: BENCHMARKING PARTICIPATING MINES
As mentioned above, the nine participants in the study included three iron ore mines, fourgold mines and two oil sands operations (for which only mining energy data were collected).In all cases, the mine operations reported their energy consumption and costs for the fullcalendar year 2000.
For the nine mines, total energy expenditures of $228 million were incurred for the calendaryear 2000. The most heavily used fuels were diesel (235 million litres) and electricity(2265 gigawatt hours). Together, these two energy sources accounted for more than 75 percent of the total energy (kWhe) consumed at the mines.
The mines in the sample collectively produced over 260 million tonnes of ore during 2000 and removed a comparable amount of waste rock. The volume of ore mined duringthe year varied from less than 4 million tonnes to over 60 million tonnes at the largestmine. Total material removed (ore plus waste rock) ranged from just under 20 milliontonnes to over 120 million tonnes. Stripping ratios (waste rock : ore tonnage) varied considerably, from 0.04 to 6.05. This variation has a significant influence on the costs andenergy consumption per tonne of ore mined that is reported in Sections 3.2 and 3.3 of thisstudy. In Section 3.4, however, we compare the mining operations on the basis of totaltonnage removed (ore plus waste), a comparison that removes the influence of the strippingratios on the comparisons.
The energy benchmarking results will be presented as we compare:
1. the costs across the participants for the individual energy sources;
2. the mining operations for the nine establishments; and
3. the results for the concentration operations of seven facilities.
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
153.1 Comparative Unit Costs for Energy
There are very significant differences between the lowest and highest unit costs reportedfor the sources of energy used at the mining operations in the study sample. As illus-trated below, the range of unit costs for each energy category is very wide (from 118 to 3 849 percent). The unit energy costs are compared in the figures below.
Figure 3.1 – Range of Unit Energy Costs
Figure 3.2 – Comparative Unit Energy Costs (CAN$)
Highest as % of Lowest
118 177 208 225 341
3 849
0
500
1 000
1 500
2 000
2 500
3 000
3 500
4 000
Bunker C Oil
Gasoline Diesel Propane ElectricityBlasting Fuels
Electricity ($/kWh)
$/kWh
1 2 3 4 5 6 7 8 9
Diesel ($/litre)
1 2 3 4 5 6 7 8 9
$/litre
0.002 0.004
0.035 0.039 0.039 0.0420.057
0.0830.092
0.23
0.330.37 0.38 0.39 0.40
0.43 0.430.48
0.00
0.02
0.04
0.06
0.08
0.10
0.00
0.10
0.20
0.30
0.40
0.50
16
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
Figure 3.2 (cont.) – Comparative Unit Energy Costs (CAN$)
1 2 3 4 5 6 7 8
$/litre
Gasoline ($/litre)
Propane ($/litre)
$/litre
1 2 3 4 5 6
Blasting Fuels ($/kg of explosive)
1 2 3 4 5 6 7
$/kg
1 2 3
$/litre
Bunker C Oil ($/litre)
0.380.45
0.57 0.59 0.59 0.590.65 0.67
0.28 0.29 0.330.44
0.54
0.94
0.32 0..330.44
0.49 0.50
0.67 0.72
0.20 0.20
0.24
0.000.100.200.300.400.500.600.700.80
0.00
0.20
0.40
0.60
0.80
1.00
0.000.100.200.300.400.500.600.700.80
0.00
0.05
0.10
0.15
0.20
0.25
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
173.2 Inter-Mine Comparative Energy Costs – Total Operations
Sufficient information was received from seven open-pit mining operations to make compar-isons at the “total operations” level (mining and milling/concentrating costs and energyconsumption per kilotonne of ore mined or processed) and for each of the stages of pro-duction (drilling, blasting, loading/excavating, hauling, crushing, grinding, etc.). For thetwo oil sands projects in the sample, only mining data was collected. For heap leach goldmines in the sample, costs were separated for ore destined for the milling process versus oretreated on leach pads, and the “mill ore” costs are reported here.
In all cases, the energy costs were compared based on Canadian dollars per kilotonne (million kilograms1) of ore mined. These unit costs, in turn, were subdivided into an energycost component (dollars per kWh equivalent) and a usage component (kWh equivalent perkilotonne of ore mined). The energy costs for total operations represent the average costper kilotonne of ore mined plus the average cost per kilotonne of ore milled/concentrated.This concept is captured using the phrase “$ per kilotonne of ore processed” (i.e. processedin the mining and the concentrating operations). The figure below summarizes the totalenergy costs per kilotonne of ore mined and ore milled/concentrated for the seven minesthat reported all data for this study.
1 ONE TONNE (1 000 KILOGRAMS) EQUALS 2 204.6 LBS.
18
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
Figure 3.3 – Energy Costs: Total Operations
Energy Cost
$ per kilotonne of ore processed
1 2 3 4 5 6 7
1 2 3 4 5 6 7
1 2 3 4 5 6 7
Energy Consumption
kWhe per kilotonne of ore processed
$ per kWhe
Unit Energy Cost
639 8881 266
2 1062 855
4 165 4 482
26 917 31 414 33 065
46 27453 301
62 38771 104
0.019 0.020
0.0470.054
0.063 0.064 0.067
0
1 000
2 000
3 000
4 000
5 000
010 00020 00030 00040 00050 00060 00070 00080 000
0.000.010.020.030.040.050.060.070.08
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
19Figure 3.4 – Average Costs by Stage of Production
Drill
ing
Blas
ting
Exca
vatio
n Hand
ling
Drill
ing
Blas
ting Ex
cava
ting
Tran
spor
t
Dewa
terin
g
Crus
hing
Grin
ding
Othe
r Pro
cess
ing
Tran
spor
t
Min
e Su
ppor
t
Taili
ngs
Proc
ess
Wat
er
Othe
r Pl
ant
G&A
Total Mill/Concentrator Operations
Total MiningOre
Excavation
Waste Rock Removal
13.1
5
170.
52
26.5
2
116.
43
21.3
8
348.
00
5.71
182.
78
24.3
8 88.7
5
301.
62
24.4
6
46.0
7
720.
15
34.9
1
174.
41
163.
17
33.7
5
24.8
5
18.5
2
449.
61
19.5
7
1 18
9.33
Wei
ghte
d Av
erag
e $/
kilo
tonn
e
Total Operations
20
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
Figure 3.5 – Average Energy Consumption by Stage of Production
Exca
vatio
n
Tran
spor
t
Tran
spor
t
Proc
ess
Wat
er
Othe
r Pla
nt G &
A
Total Operations
Total Mill/Concentrator Operations
Total Mining
Waste Rock RemovalWei
ghte
d Av
erag
e kW
h e /
kilo
tonn
e
1 64
7
20 9
89
366
504 69
3
3 49
2
636
5 69
1
271
453 78
4
2 79
3
4 30
1
355 1
419
11 7
66
1 32
0
5 26
9
9 47
3 1 75
4
1 52
7 752
33 5
07
Ore Excavation
Drill
ing
Blas
ting
Exca
vatin
g
Dewa
terin
g
Crus
hing
Grin
ding
Othe
r Pro
cess
ing
Min
e Su
ppor
t
Taili
ngs
Drill
ing
Blas
ting
Hand
ling
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
213.3 Inter-Mine Comparative Energy Costs – Mining Operations
3.3.1 Total Mining Operations
The total energy costs for open-pit mining for the nine operations are shown below. Asillustrated, the energy costs vary from $170 per kilotonne of ore mined to $3,120 per kilotonne. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore mined) 3 120 : 170 1 830
Energy Consumption (kWhe/kilotonne of ore mined) 42 474 : 7 006 606
Unit Energy Cost ($/kWhe) 0.073 : 0.022 331
The total costs shown here cover drilling, blasting, excavating, hauling, pit dewatering, andmine support equipment, road maintenance and service equipment. Any in-pit crushing orrehandling of ore from stockpiles is excluded.
22
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
Figure 3.6 – Total Energy Costs: Mining Operations
Energy Cost
$ per kilotonne of ore mined
1 2 3 4 5 6 7 8 9
1 2 3 4 5 6 7 8 9
1 2 3 4 5 6 7 8 9
Energy Consumption
kWhe per kilotonne of ore mined
$ per kWhe
Unit Energy Cost
170 231527 534 552
817
1 793 1 821
3 120
7 006 7 694 8 949 10 32111 264 13 322
26 88433 855
42 474
0.0220.033
0.049 0.052 0.0530.059 0.061
0.068 0.073
0500
1 0001 5002 0002 5003 0003 500
0
10 000
20 000
30 000
40 000
50 000
0.000.010.020.030.040.050.060.070.08
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
233.3.2 Waste Rock Operations – Stages of Production
Drilling (Waste Rock)
The cost for waste rock drilling energy varied from $0.08 to $144.00 per kilotonne of oremined for seven drilling operations. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore mined) 144.00 : 0.08 179 800
Energy Consumption (kWhe/kilotonne of ore mined) 3 618 : 35 10 439
Unit Energy Cost ($/kWhe) 0.045 : 0.002 1 858
Figure 3.7 – Drilling (Waste Rock) Energy Costs
Energy Cost
$ per kilotonne of ore mined
Energy Consumption
1 2 3 4 5 6 7
1 2 3 4 5 6 7
1 2 3 4 5 6 7
kWhe per kilotonne of ore mined
$ per kWhe
Unit Energy Cost
6.00 8.00
44.00
81.00
144.00
0.430.08
35 103 177 200
1 2081 806
3 618
0.002 0.004
0.0340.037 0.039 0.040
0.045
0
30
60
90
120
150
0500
1 0001 5002 0002 5003 0003 5004 000
0.00
0.01
0.02
0.03
0.04
0.05
24
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
Blasting (Waste Rock)
The blasting energy costs for waste rock varied from $79 to $1,255 per kilotonne of oremined. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore mined) 1 255 : 79 1 588
Energy Consumption (kWhe/kilotonne of ore mined) 1 845 : 203 909
Unit Energy Cost ($/kWhe) 0.680 : 0.186 366
Figure 3.8 – Blasting (Waste Rock) Energy Costs
Energy Cost
$ per kilotonne of ore mined
1 2 3 4 5 6 7
1 2 3 4 5 6 7
1 2 3 4 5 6 7
Energy Consumption
kWhe per kilotonne of ore mined
$ per kWhe
Unit Energy Cost
0
300
600
900
1 200
1 500
0
500
1 000
1 500
2 000
0.00.10.20.30.40.50.60.70.8
79 84 101205 239
516
1 255
203 217425 535
1 2211 383
1 845
0.186 0.196
0.373 0.384 0.415 0.466
0.680
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
25Loading/Excavating (Waste Rock)
The energy costs for loading/excavating waste rock varied from $5 to $277 per kilotonneof ore mined. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore mined) 277 : 5 5 213
Energy Consumption (kWhe/kilotonne of ore mined) 6 209 : 332 1 868
Unit Energy Cost ($/kWhe) 0.054 : 0.016 341
Figure 3.9 – Excavating (Waste Rock) Energy Costs
Energy Cost
$ per kilotonne of ore mined
Energy Consumption
1 2 3 4 5 6 7 8 9
1 2 3 4 5 6 7 8 9
1 2 3 4 5 6 7 8 9
kWhe per kilotonne of ore mined
$ per kWhe
Unit Energy Cost
0
50
100
150
200
250
300
01 0002 0003 0004 0005 0006 0007 0008 000
0.00
0.01
0.02
0.03
0.04
0.05
0.06
5 11 14 18 2140
61
175
277
332 336 380 424 6581 089 1 140
3 750
6 209
0.0160.025
0.0320.037 0.037
0.045 0.0470.053 0.054
26
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
Waste Rock Transport
The energy costs for hauling waste rock varied from $18 to $887 per kilotonne of oremined. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore mined) 887 : 18 4 986
Energy Consumption (kWhe/kilotonne of ore mined) 22 307 : 442 5 052
Unit Energy Cost ($/kWhe) 0.045 : 0.021 208
Figure 3.10 – Waste Rock Transport Energy Costs
1 2 3 5 74 6 8 9
1 2 3 5 74 6 8 9
1 2 3 5 74 6 8 9
18 54 69 75 114 126
338
579
887
442 1 461 2 421 3 211 3 229 3 6707 577
15 817
22 307
0.021
0.0310.034 0.035 0.037 0.037
0.040 0.0400.045
0
200
400
600
800
1 000
0
5 000
10 000
15 000
20 000
25 000
0.00
0.01
0.02
0.03
0.04
0.05
Energy Cost
$ per kilotonne of ore mined
Energy Consumption
kWhe per kilotonne of ore mined
$ per kWhe
Unit Energy Cost
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
27Waste Rock Handling
The energy costs for handling waste rock after transport varied from $7 to $78 per kilotonneof ore mined. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore mined) 78 : 7 1 076
Energy Consumption (kWhe/kilotonne of ore mined) 1 743 : 298 586
Unit Energy Cost ($/kWhe) 0.045 : 0.021 208
Figure 3.11 – Waste Rock Handling Energy Costs
1 2 3 4 5 6 7 8 9
1 2 3 4 5 6 7 8 9
1 2 3 4 5 6 7 8 9
7 10 1319 23
29 3239
78
298 337 345538 567
7361 036 1 079
1 743
0.021
0.0310.034 0.035 0.037 0.037 0.040 0.040
0.045
01020304050607080
0
500
1 000
1 500
2 000
0.00
0.01
0.02
0.03
0.04
0.05
Energy Cost
$ per kilotonne of ore mined
Energy Consumption
kWhe per kilotonne of ore mined
$ per kWhe
Unit Energy Cost
28
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
3.3.3 Ore Mining Operations – Stages of Production
Drilling (Ore)
The drilling energy costs varied from $0.13 to $29.00 per kilotonne of ore mined forseven drilling operations. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore mined) 29.00 : 0.13 21 969
Energy Consumption (kWhe/kilotonne of ore mined) 641 : 54 1 191
Unit Energy Cost ($/kWhe) 0.045 : 0.002 1 858
Figure 3.12 – Drilling (Ore) Energy Costs
1 2 3 4 5 6 7
1 2 3 4 5 6 7
1 2 3 4 5 6 7
2.007.00 7.00
10.00
24.00
29.00
0.13
54185 217
281385
599 641
0.002 0.004
0.034 0.037 0.039 0.0400.045
0
5
10
15
20
25
30
0100200300400500600700800
0.00
0.01
0.02
0.03
0.04
0.05
Energy Cost
$ per kilotonne of ore mined
Energy Consumption
kWhe per kilotonne of ore mined
$ per kWhe
Unit Energy Cost
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
29Blasting (Ore)
The energy costs for blasting ore varied from $56 to $208 per kilotonne of ore mined.The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore mined) 208 : 56 374
Energy Consumption (kWhe/kilotonne of ore mined) 520 : 284 183
Unit Energy Cost ($/kWhe) 0.680 : 0.186 366
Figure 3.13 – Blasting (Ore) Energy Costs
1 2 3 4 5 6 7
1 2 3 4 5 6 7
1 2 3 4 5 6 7
5697
164183 186
202 208
284 305353
482 488 492 520
0.186 0.196
0.372 0.386 0.415 0.466
0.680
0
50
100
150
200
250
0
100
200
300
400
500
600
0.000.100.200.300.400.500.600.700.80
Energy Cost
$ per kilotonne of ore mined
Energy Consumption
kWhe per kilotonne of ore mined
$ per kWhe
Unit Energy Cost
30
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
Loading/Excavating Ore
The energy costs for loading/excavating ore varied from $10 to $98 per kilotonne of oremined. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore mined) 98 : 10 954
Energy Consumption (kWhe/kilotonne of ore mined) 2 201 : 407 541
Unit Energy Cost ($/kWhe) 0.053 : 0.014 378
Figure 3.14 – Excavating (Ore) Energy Costs
1 3 5 7 92 4 6 8
1 3 5 7 92 4 6 8
1 3 5 7 92 4 6 8
1017 22 22
29 34 35
62
98
407 461 621 726 857 938 1 061
1 658
2 201
0.014
0.0260.033
0.037 0.037 0.0370.045 0.047
0.053
0
20
40
60
80
100
0
500
1 000
1 500
2 000
2 500
0.00
0.01
0.02
0.03
0.04
0.05
0.06
Energy Cost
$ per kilotonne of ore mined
Energy Consumption
kWhe per kilotonne of ore mined
$ per kWhe
Unit Energy Cost
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
31Ore Transport
The energy costs for hauling ore to the crusher or stockpile varied from $50 to $162 perkilotonne of ore mined. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore mined) 162 : 50 327
Energy Consumption (kWhe/kilotonne of ore mined) 4 432 : 2 020 219
Unit Energy Cost ($/kWhe) 0.045 : 0.021 208
Figure 3.15 – Ore Transport Energy Costs
1 3 5 7 92 4 6 8
1 3 5 7 92 4 6 8
1 3 5 7 92 4 6 8
5063
88 89120 121
135 135162
2 020 2 231 2 316 2 3592 687
3 4173 933 4 106
4 432
0.021
0.031 0.033 0.034 0.035 0.037 0.0370.040
0.045
0
50
100
150
200
0
1 000
2 000
3 000
4 000
5 000
0.00
0.01
0.02
0.03
0.04
0.05
Energy Cost
$ per kilotonne of ore mined
Energy Consumption
kWhe per kilotonne of ore mined
$ per kWhe
Unit Energy Cost
32
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
Mine Dewatering
The energy costs for mine dewatering varied from $0.00 to $454.00 per kilotonne of oremined. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore mined) 454.00 : 0.00 n/a
Energy Consumption (kWhe/kilotonne of ore mined) 4 920 : 0 n/a
Unit Energy Cost ($/kWhe) 0.092 : 0.000 n/a
Figure 3.16 – Mine Dewatering Energy Costs
1 2 3 4 5 6 7
1 2 3 4 5 6 7
1 2 3 4 5 6 7
0
100
200
300
400
500
0
1 000
2 000
3 000
4 000
5 000
0.00
0.02
0.04
0.06
0.08
0.10
5.00 6.00 12.00
454.00
1.020.990.00
0 73 131 247 301 414
4 920
0.000 0.002 0.004
0.039 0.039
0.0830.092
Energy Cost
$ per kilotonne of ore mined
Energy Consumption
kWhe per kilotonne of ore mined
$ per kWhe
Unit Energy Cost
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
33Mine Support Equipment and Services
This category includes energy consumption reported by participants for mine supportequipment, road maintenance and service equipment and facilities. The energy costs for variousmine support equipment and services ranged from $12 to $280 per kilotonne of ore mined.The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore mined) 280 : 12 2 376
Energy Consumption (kWhe/kilotonne of ore mined) 6 463 : 549 1 177
Unit Energy Cost ($/kWhe) 0.048 : 0.017 288
Figure 3.17 – Mine Support Equipment and Services Energy Costs
1 2 3 4 5 6 7 8 9
12 2946 46 56 70 86 97
280
0
50
100
150
200
250
300
1 2 3 4 5 6 7 8 9
0.0170.021
0.0290.034
0.0380.043 0.043
0.047 0.048
1 2 3 4 5 6 7 8 9
549 6891 211 1 347 1 815 2 014
2 4083 365
6 463
01 0002 0003 0004 0005 0006 0007 0008 000
Energy Cost
$ per kilotonne of ore mined
Energy Consumption
kWhe per kilotonne of ore mined
$ per kWhe
Unit Energy Cost
0.00
0.01
0.02
0.03
0.04
0.05
34
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
3.3.4 Comparisons Based on Total Material Removed
Drilling
The drilling energy costs varied from $0.13 to $29.00 per kilotonne of material removed(ore plus waste rock) for seven drilling operations, as illustrated below. The range of costsand efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of material removed) 29.00 : 0.13 21 969
Energy Consumption (kWhe/kilotonne of material removed) 641 : 55 1 173
Unit Energy Cost ($/kWhe) 0.045 : 0.002 1 858
Figure 3.18 – Drilling Energy Costs
1 2 3 4 5 6 7
1 2 3 4 5 6 7
1 2 3 4 5 6 7
0
5
10
15
20
25
30
0100200300400500600700800
0.00
0.01
0.02
0.03
0.04
0.05
2.007.00 7.00
10.00
24.00
29.00
0.13
55
184 217281
468598 641
0.002 0.004
0.034 0.037 0.039 0.0400.045
Energy Cost
$ per kilotonne of material removed
Energy Consumption
kWhe per kilotonne of material removed
$ per kWhe
Unit Energy Cost
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
35The influence of the size of the mining operation on energy consumption in drilling activitiesis explored in the figure below. There appears to be a very strong relationship between thedrilling energy per kilotonne of material removed (i.e. rock broken) and the total volumeof material removed at the mine. The largest operations consume less than one half of the energy per kilotonne in drilling operations that is reported by the smaller mines in thestudy sample.
Figure 3.19 – Scale Economies: Drilling
Blasting
The energy costs for blasting varied from $56 to $275 per kilotonne of material removed(ore plus waste rock). The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of material removed) 275 : 56 494
Energy Consumption (kWhe/kilotonne of material removed) 662 : 284 233
Unit Energy Cost ($/kWhe) 0.680 : 0.186 366
0
250
500
750
0 100
Millions of Tonnes of Material Removed
kWh e
per
kilo
tonn
e
36
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
Figure 3.20 – Blasting Energy Costs
We examined the relationship between the size of the open-pit mining operations and theprice paid for blasting fuels. As indicated in the figure below, the larger operations tend tobe able to leverage their substantial requirements for blasting fuels into lower prices from suppliers.
Figure 3.21 – Economies of Scale: Purchase Price of Blasting Fuels
1 2 3 4 5 6 7
1 2 3 4 5 6 7
1 2 3 4 5 6 7
5697
164 183 187 208
275
284 305 352
486 491 520
662
0.186 0.196
0.373 0.385 0.415 0.466
0.680
0
50
100
150
200
250
300
0100200300400500600700800
0.00.10.20.30.40.50.60.70.8
Energy Cost
$ per kilotonne of material removed
Energy Consumption
kWhe per kilotonne of material removed
$ per kWhe
Unit Energy Cost
$0.00
$0.20
$0.40
$0.60
$0.80
0 100Millions of Tonnes of Material Removed
$ pe
r kW
h e
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
37Material Loading/Excavating
The energy costs for loading/excavating ore and waste rock varied from $15 to $98 perkilotonne of material removed. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of material removed) 98 : 15 657
Energy Consumption (kWhe/kilotonne of material removed) 2 202 : 389 566
Unit Energy Cost ($/kWhe) 0.053 : 0.015 364
Figure 3.22 – Excavating Energy Costs
1 3 5 7 92 4 6 8
1 3 5 7 92 4 6 8
1 3 5 7 92 4 6 8
15 17 18 18 2229 35 36
98
389 407 455620 702
969 1 018 1 061
2 202
0.015
0.0260.033
0.037 0.0370.045 0.047 0.047
0.053
0
20
40
60
80
100
0
500
1 000
1 500
2 000
2 500
0.00
0.01
0.02
0.03
0.04
0.05
0.06
Energy Cost
$ per kilotonne of material removed
Energy Consumption
kWhe per kilotonne of material removed
$ per kWhe
Unit Energy Cost
38
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
The excavating/loading operations at open-pit mines would appear to generate significanteconomies of scale. Larger mines are able to deploy extremely large and expensive (electric)shovels that would not be cost-efficient in smaller mining operations. The figure belowexamines the economies of scale reported in loading operations at the nine mines in the study.Perhaps surprisingly, the energy consumption (kWhe per kilotonne of material removed)reported for excavating operations is not much higher at the smaller mines participating inthis study.
Figure 3.23 – Economies of Scale: Excavating
Hauling
The energy costs for hauling material from the pit to the crusher, stockpile or dump variedfrom $65 to $158 per kilotonne of material removed (ore plus waste rock). The range ofcosts and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of material removed) 158 : 65 243
Energy Consumption (kWhe/kilotonne of material removed) 4 591 : 2 359 195
Unit Energy Cost ($/kWhe) 0.045 : 0.021 208
0
1 000
2 000
3 000
0 150Millions of Tonnes of Material Removed
kWh e
per
kilo
tonn
e
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
39Figure 3.24 – Transport/Hauling Energy Costs
Hauling is another mining operation that can generate economies of scale since the largestmines are more able to use very large trucks (over 200 tons). On the basis of the data illus-trated in the figure below, however, the larger mines do not appear to be realizing any savingsin energy consumption per kilotonne of material removed compared with the smalleropen-pit mines in the study.
Figure 3.25 – Economies of Scale: Hauling
1 3 5 7 92 4 6 8
1 3 5 7 92 4 6 8
1 3 5 7 92 4 6 8
65 7588
112 120 138 138 147 158
2 359 2 403 2 6873 028 3 175 3 483
3 7594 360 4 591
0.021
0.0310.034 0.034 0.035 0.037 0.037
0.0400.045
0
50
100
150
200
0
1 000
2 000
3 000
4 000
5 000
0.00
0.01
0.02
0.03
0.04
0.05
Energy Cost
$ per kilotonne of material removed
Energy Consumption
kWhe per kilotonne of material removed
$ per kWhe
Unit Energy Cost
0
1 000
2 000
3 000
4 000
5 000
0 150Millions of Tonnes of Material Removed
kWh e
per
kilo
tonn
e
40
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
Mine Dewatering
The energy costs for mine dewatering varied from $0.00 to $86.00 per kilotonne of materialremoved. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of material removed) 86.00 : 0.00 n/a
Energy Consumption (kWhe/kilotonne of material removed) 928 : 0 n/a
Unit Energy Cost ($/kWhe) 0.002 : 0.000 n/a
Figure 3.26 – Mine Dewatering Energy Costs
1 2 3 4 5 6 7
1 2 3 4 5 6 7
1 2 3 4 5 6 7
1.00 3.00 6.00
86.00
0.980.610.00
0 34 40144
236 256
928
0.000 0.002 0.004
0.039 0.039
0.0830.092
0
20
40
60
80
100
0
200
400
600
800
1 000
0.00
0.02
0.04
0.06
0.08
0.10
Energy Cost
$ per kilotonne of material removed
Energy Consumption
kWhe per kilotonne of material removed
$ per kWhe
Unit Energy Cost
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
41Mine Support Equipment and Services2
The energy costs for various mine support equipment and services ranged from $6 to $44 per kilotonne of material removed. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of material removed) 44 : 6 684
Energy Consumption (kWhe/kilotonne of material removed) 2 078 : 301 691
Unit Energy Cost ($/kWhe) 0.048 : 0.017 288
Figure 3.27 – Mine Support Equipment and Services Energy Costs
2 THIS CATEGORY INCLUDES ENERGY CONSUMPTION REPORTED BY PARTICIPANTS FOR MINE SUPPORT EQUIPMENT, ROAD
MAINTENANCE AND SERVICE EQUIPMENT AND FACILITIES.
1 3 5 7 92 4 6 8
1 3 5 7 92 4 6 8
1 3 5 7 92 4 6 8
6
16 16
25 2634 35
4044
301 342 373527 666
9171 150 1 291
2 078
0.0170.021
0.0290.034
0.0380.043 0.043
0.047 0.048
0
10
20
30
40
50
0
500
1 000
1 500
2 000
2 500
0.00
0.01
0.02
0.03
0.04
0.05
Energy Cost
$ per kilotonne of material removed
Energy Consumption
kWhe per kilotonne of material removed
$ per kWhe
Unit Energy Cost
42
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
Total Mining Costs per Kilotonne Removed
The total energy costs for mining operations ranged from $89 to $483 per kilotonne ofmaterial removed. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of material removed) 483 : 89 510
Energy Consumption (kWhe/kilotonne of material removed) 8 035 : 3 231 249
Unit Energy Cost ($/kWhe) 0.074 : 0.022 334
Figure 3.28 – Total Mining Costs
1 3 5 7 92 4 6 8
1 3 5 7 92 4 6 8
1 3 5 7 92 4 6 8
0
100
200
300
400
500
0
2 000
4 000
6 000
8 000
10 000
0.000.010.020.030.040.050.060.070.08
89 107
312 322 324381
439 456 483
3 2314 030
5 924 5 982 6 108 6 161 6 441 6 5818 035
0.0220.033
0.048 0.052 0.0540.060 0.062
0.069 0.074
Energy Cost
$ per kilotonne of material removed
Energy Consumption
kWhe per kilotonne of material removed
$ per kWhe
Unit Energy Cost
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
43The effect of economies of scale on the energy consumption in total mining operationswithin the nine mines in the study is shown in the figure below. The two largest opera-tions, the oil sands operations, which have no drilling or blasting operations, recorded thelowest energy consumption per kilotonne of material removed. There was, however, littleevidence of any economies of scale for energy consumption among the seven “hard rock”open-pit mines in the study.
Figure 3.29 – Economies of Scale: Total Mining Energy
3.4 Inter-Mine Comparative Energy Costs – Mill/Concentrator Operations
3.4.1 Total Mill/Concentrator Operations
The total energy costs for open-pit mining for seven operations are shown below. As illus-trated, the energy costs vary from $105 per kilotonne of ore processed to $2,367 per kilotonne.The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore processed) 2 367 : 105 2 254
Energy Consumption (kWhe/kilotonne of ore processed) 35 701 : 13 144 272
Unit Energy Cost ($/kWhe) 0.083 : 0.005 1 681
0
3 000
6 000
9 000
0 150Millions of Tonnes of Material Removed
kWh e
per
kilo
tonn
e
44
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
The total costs shown here cover crushing, grinding, all other concentration, extractionand recovery operations, tailings treatment, process water supply, and other plant energy.Any in-pit crushing has been included with the primary crushing operations at the mill.
Figure 3.30 – Total Energy Costs: Mill/Concentrator Operations
1 2 4 5 63 7
1 2 4 5 63 7
1 2 4 5 63 7
105353 431
9601 209
1 523
2 367
13 144
21 229 21 29823 811 24 540
28 449
35 701
0.005 0.010
0.0330.039
0.051
0.0720.083
0
500
1 000
1 500
2 000
2 500
05 000
10 00015 00020 00025 00030 00035 00040 000
0.00
0.02
0.04
0.06
0.08
0.10
Energy Cost
$ per kilotonne of ore processed
Energy Consumption
kWhe per kilotonne of ore processed
$ per kWhe
Unit Energy Cost
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
453.4.2 Mill/Concentrator Operations – Stages of Production
Crushing
Energy costs for crushing ore varied from $2 to $160 per kilotonne of ore processed forseven operations. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore processed) 160 : 2 8 126
Energy Consumption (kWhe/kilotonne of ore processed) 2 804 : 253 1 110
Unit Energy Cost ($/kWhe) 0.092 : 0.003 2 957
Figure 3.31 – Crushing Energy Costs
1 2 3 4 5 6 7
1 2 3 4 5 6 7
1 2 3 4 5 6 7
2 3
39 4660
79
160
253 427 561
1 065
1 9452 358
2 804
0.003 0.008
0.0250.041
0.057
0.0830.092
0
50
100
150
200
0
500
1 000
1 500
2 000
2 500
3 000
0.00
0.02
0.04
0.06
0.08
0.10
Energy Cost
$ per kilotonne of ore processed
Energy Consumption
kWhe per kilotonne of ore processed
$ per kWhe
Unit Energy Cost
46
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
Grinding
Energy costs for grinding ore varied from $6 to $1,507 per kilotonne of ore processed.The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore processed) 1 507 : 6 23 815
Energy Consumption (kWhe/kilotonne of ore processed) 16 320 : 2 639 619
Unit Energy Cost ($/kWhe) 0.092 : 0.002 3 849
Figure 3.32 – Grinding Energy Costs
1 2 3 4 65 7
1 2 3 4 65 7
1 2 3 4 65 7
6 21 139
582 603 698
1 507
2 639 3 6204 957
7 280
12 23214 930
16 320
0.002 0.004
0.039 0.039
0.057
0.0830.092
0
500
1 000
1 500
2 000
0
5 000
10 000
15 000
20 000
0.00
0.02
0.04
0.06
0.08
0.10
Energy Cost
$ per kilotonne of ore processed
Energy Consumption
kWhe per kilotonne of ore processed
$ per kWhe
Unit Energy Cost
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
47Crushing and Grinding Combined
Energy costs for crushing and grinding combined varied from $10 to $1,547 per kilotonneof ore processed. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore processed) 1 547 : 10 16 014
Energy Consumption (kWhe/kilotonne of ore processed) 16 874 : 3 704 456
Unit Energy Cost ($/kWhe) 0.092 : 0.003 3 539
Figure 3.33 – Crushing and Grinding Energy Costs
1 2 3 4 5 6 7
1 2 3 4 5 6 7
1 2 3 4 5 6 7
10 23199
649 661859
1 547
3 7045 210 5 978
7 842
15 03516 747 16 874
0.003 0.005
0.033 0.039
0.057
0.0830.092
0
500
1 000
1 500
2 000
0
5 000
10 000
15 000
20 000
0.00
0.02
0.04
0.06
0.08
0.10
Energy Cost
$ per kilotonne of ore processed
Energy Consumption
kWhe per kilotonne of ore processed
$ per kWhe
Unit Energy Cost
48
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
All Other Mill/Concentrator
This category of mill/concentrator costs aggregates energy consumed in the separation,filtering and drying processes for iron ore mines, and included in the separation are carbon-in-leach (CIL) and carbon-in-column (CIC) circuits, stripping, electrowinning andrefining operations at gold mines. These costs varied from $45 to $753 per kilotonne ofore processed. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore processed) 753 : 45 1 668
Energy Consumption (kWhe/kilotonne of ore processed) 26 105 : 2 744 951
Unit Energy Cost ($/kWhe) 0.070 : 0.005 1 334
Figure 3.34 – Energy Costs: All Other Processing
1 2 3 4 5 6 7
1 2 3 4 5 6 7
1 2 3 4 5 6 7
45107 129 170
327
623
753
2 744 4 480 4 6508 666 9 331 10 827
26 105
0.0050.013
0.0290.037 0.039
0.067 0.070
0100200300400500600700800
0
5 000
10 000
15 000
20 000
25 000
30 000
0.000.010.020.030.040.050.060.070.08
Energy Cost
$ per kilotonne of ore processed
Energy Consumption
kWhe per kilotonne of ore processed
$ per kWhe
Unit Energy Cost
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
49Tailings Treatment
Energy costs for tailings treatment varied from $5 to $100 per kilotonne of ore processed.The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore processed) 100 : 5 1 844
Energy Consumption (kWhe/kilotonne of ore processed) 2 261 : 245 924
Unit Energy Cost ($/kWhe) 0.092 : 0.002 3 849
Figure 3.35 – Energy Costs: Tailings Treatment
1 2 3 4 5 6 7
1 2 3 4 5 6 7
1 2 3 4 5 6 7
5 923
4958
85100
245
1 0231 261
1 5031 751
2 0492 261
0.002 0.004
0.039 0.039
0.057
0.0830.092
0
20
40
60
80
100
0
500
1 000
1 500
2 000
2 500
0.00
0.02
0.04
0.06
0.08
0.10
Energy Cost
$ per kilotonne of ore processed
Energy Consumption
kWhe per kilotonne of ore processed
$ per kWhe
Unit Energy Cost
50
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
Process Water Supply
Energy costs for process water supply varied from $5 to $90 per kilotonne of ore processed.The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore processed) 90 : 5 1 671
Energy Consumption (kWhe/kilotonne of ore processed) 2 249 : 79 2 864
Unit Energy Cost ($/kWhe) 0.092 : 0.002 3 849
Figure 3.36 – Process Water Supply Energy Costs
1 2 3 4 5 6 7
1 2 3 4 5 6 7
1 2 3 4 5 6 7
0
20
40
60
80
100
0
500
1 000
1 500
2 000
2 500
0.00
0.02
0.04
0.06
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0.10
5 7 820
3046
90
79
518 523
1 089 1 182
1 9782 249
0.002 0.004
0.039 0.039
0.057
0.0830.092
Energy Cost
$ per kilotonne of ore processed
Energy Consumption
kWhe per kilotonne of ore processed
$ per kWhe
Unit Energy Cost
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
RESULTS: BENCHMARKING PARTICIPATING MINES 3
51Other Plant Energy
Other plant energy costs varied from $5 to $123 per kilotonne of ore processed. The rangeof costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore processed) 123 : 5 2 254
Energy Consumption (kWhe/kilotonne of ore processed) 3 326 : 552 603
Unit Energy Cost ($/kWhe) 0.069 : 0.004 1 745
Figure 3.37 – Other Plant Energy Costs
1 2 3 4 5 6
1 2 3 4 5 6
1 2 3 4 5 6
520
3851
76
123
552
1 3821 852 2 013
3 143 3 326
0.004 0.006
0.0270.038 0.039
0.069
0
30
60
90
120
150
0500
1 0001 5002 0002 5003 0003 500
0.000.010.020.030.040.050.060.070.08
Energy Cost
$ per kilotonne of ore processed
Energy Consumption
kWhe per kilotonne of ore processed
$ per kWhe
Unit Energy Cost
52
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
3 RESULTS: BENCHMARKING PARTICIPATING MINES
3.5 General and Administrative
The total energy costs for general and administrative operations for seven operations areshown below. As illustrated, the reported energy costs vary from $1 per kilotonne of oremined to $153 per kilotonne. The range of costs and efficiencies is as follows:
Range High : LowHigh : Low Percent
Energy Cost ($/kilotonne of ore mined) 153 : 1 15 504
Energy Consumption (kWhe/kilotonne of ore mined) 4 818 : 83 5 819
Unit Energy Cost ($/kWhe) 0.059 : 0.004 1 503
The total costs shown here cover energy consumed in operating guardhouses, parking lots,assay laboratories, camps, etc.
Figure 3.38 – General and Administrative Energy Costs
1 2 3 4 65 7
1 2 3 4 65 7
1 2 3 4 65 7
0
50
100
150
200
0
1 000
2 000
3 000
4 000
5 000
0.00
0.01
0.02
0.03
0.04
0.05
0.06
5 7 1730
74
153
1
83 252 451 5031 236
1 877
4 818
0.004 0.006
0.0320.039 0.039
0.055 0.059
Energy Cost
$ per kilotonne of ore mined
Energy Consumption
kWhe per kilotonne of ore mined
$ per kWhe
Unit Energy Cost
POTENTIAL SAVINGS:
ACHIEVING BENCHMARK
STANDARDS4
54
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
4 POTENTIAL SAVINGS: ACHIEVING BENCHMARK STANDARDS
4. POTENTIAL SAVINGS: ACHIEVING BENCHMARK STANDARDS
4.1 Context
In this section, we present some general estimates of potential energy savings from attainingthe performance of the most energy-efficient operations. To determine the related potentialcost savings, we used weighted average costs for each source of energy.
It should be noted, however, that the potential savings identified may not be realizable fora number of practical reasons. For example, savings may be related to economies of scaleor the nature of the ore body, or customer requirements may dictate the use of a particulartechnology precluding the use of a more energy-efficient technology.
At the same time, there may be some offsetting arguments regarding the size of the potentialsavings when considering the following:
• There are opportunities for improvement in the lowest-cost, most efficient facilities. Thefact that different firms lead in different stages of production provides even more evidenceof the potential.
• There could be operations outside the study sample that have lower-cost, more efficientoperations.
In light of the above observations, we present below a simplistic estimate of the potentialsavings achievable if each participant were to attain the most efficient level of energy con-sumption for each stage of production, using average energy source prices.
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
POTENTIAL SAVINGS: ACHIEVING BENCHMARK STANDARDS 4
554.2 Potential Energy Savings: Mining
Mining Operations (Material Removed)
Weighted Lowest Savings Average Total TotalAverage kWhe/kt kWhe/kt $/kWhe kt Savings kWhe ($M)
Drilling 291 55 236 0.031 326 2.4
Blasting 448 284 104 0.034 326 18.2
Loading 707 389 318 0.036 533 6.1
Transport 3 258 2 359 899 0.033 533 15.8
Support 704 301 403 0.032 533 6.9
Total 49.4 (36%)
With respect to mining operations, potential identified energy savings represent a cost savingof about $49 million, or approximately 36 percent.
4.3 Potential Energy Savings: Milling
Iron Ore Concentration
Weighted Lowest Savings Average Total TotalAverage kWhe/kt kWhe/kt $/kWhe kt Savings kWhe ($M)
Crushing 1 282 253 1 029 0.021 95 018 2.0
Grinding 3 983 2 639 1 344 0.017 95 018 2.2
Further 10 008 4 480 5 528 0.013 95 018 6.8Processing
Tailings 1 857 1 503 354 0.015 95 018 0.5
Process Water 1 692 1 182 510 0.014 95 018 0.7
Other 2 730 1 382 1 348 0.006 55 101 0.4
Total 12.7 (47%)
With respect to iron ore concentration operations, potential energy savings identified areabout $13 million, or approximately 47 percent.
56
BENCHMARKING THE ENERGY CONSUMPTION OF CANADIAN OPEN-PIT MINES
4 POTENTIAL SAVINGS: ACHIEVING BENCHMARK STANDARDS
Gold Milling
Weighted Lowest Savings Average Total TotalAverage kWhe/kt kWhe/kt $/kWhe kt Savings kWhe ($M)
Crushing 1 549 427 1 122 0.054 15 783 1.0
Grinding 13 009 7 280 5 729 0.063 15 783 5.7
Further 6 248 2 744 3 504 0.058 15 783 3.2Processing
Tailings 1 131 245 886 0.057 15 783 0.8
Process Water 538 79 459 0.063 15 783 0.5
Other 2 029 552 1 477 0.038 15 783 0.9
Total 11.9 (53%)
With respect to gold milling operations, potential energy savings identified are in the orderof $12 million, or approximately 53 percent.
To sum up, potential annual energy savings identified with the most efficient operation foreach production stage as the benchmark are about $74 million (about one third of totalenergy costs), as applied to the nine study participants.
On a cautionary note, we should point out that these savings are hypothetical and may notbe achievable owing to circumstances faced by each mine, i.e. the nature of the ore body,technology employed, long-term contractual obligations, etc.