Indonesian Journal of Environmental Management and Sustainability p-ISSN: 2598-6260 e-ISSN: 2598-6279 http://ijoems.com/index.php/ijems Research Article Received: 27 October 2017 Accepted: 9 February 2018 *Corresponding author email: igusman@bukitasam.co.id DOI: 10.26554/ijems.2018.2.1.7-107 Energy Efficiency and Greenhouse Gas Emissions Reduction Through Electrification Program at Tanjung Enim Mine Business Unit of PT Bukit Asam (Persero) Tbk. Iko Gusman1,Pramudita Triatmojo1, Peni Rostiarti1, Bima Arifiyanto1 1PT. BUKIT ASAM (Persero) Tbk. - Unit PertambanganTanjungEnim JalanParigi No.1-A KecamatanLawangKidul, KabupatenMuaraEnim, Sumatera Selatan - Indonesia igusman@bukitasam.co.id ABSTRACT Current global economic conditions have made the coal prices become uncertain. PT Bukit Asam (PTBA) has taken corporate action by improving operational efficiency, cost control; develop coal diversification product and also optimization in the mining operation. One of the operational efficiency programs for cost control in mining operation system is the Electrification Program. This program changed mining operations previously dominated by fuel-based mining system transformed into an electricity-based mining system for an elec- tricshovel continue with the conventional truck. Implementation of Mining Systems with electric-based mining equipment divided into several stages for short-term and long-term targets. Electrification program consist of 7 Units Electric Shovel (PC3000-6E) and 40 Units Rigid DT (Belaz75135) with target20 Million BCM in 2017 located in Banko West Mine. PTBA through the electrification program has succeeded in reducing energy consumption by 333,861.74 Joule/Years and reducing greenhouse gas emissions by 15,058.49 Ton CO2e/Year. Electrification program has successfully contributed for environmental sustainability by reducing energy consumption and greenhouse gas emissions in accordance with the vision of PTBA into a world-class energy company that cares about the environment. Keywords: Electrification, Mining system, Energy Consumption, Greenhouse Gas Emission, PTBA 1. INTRODUCTION Current global economic conditions have made the coal prices be- come uncertain. PT Bukit Asam (PTBA) has quickly responded to these conditions by improving operational efficiency, cost con- trol, diversifying export marketing including introducing focused mining patterns, while maintaining environmental sustainability. One of the operational efficiency programs for cost control and corporate development is Electrification Program where pre- viously mining operations were dominated by fuel-based mining systems. Implementation of Mining Systems with electric-based mining equipment is also designed through stages to adjust to short-term and long-term corporate targets and adjust to the read- iness of equipment. In the framework of such development, PTBA has in- vested in electricity-based mining equipment by utilizing its com- petency capacity in managing continuous mining systems and the potential of existing internal resources (Mouth Mine Power Plant) to reduce dependence on fuel consumption. Electrification pro- gram has also proven to contribute to environmental sustainabil- ity, namely the reduction of energy consumption and greenhouse gas emissions, in accordance with the vision of PTBA to be a world-class energy company that cares about the Environment. 2. EXPERIMENTAL METHOD Estimation of electricity consumption can be applied to a wide range of analyses that can be used to [1]: 1. Perform or review prefeasibility level studies by using individual estimates or linking them for estimating requirements for vertical integrated mining operations 2. Estimate the economic effects of changes in power rates and fuel costs on producing or planned mining facilities 3. Estimate a component of greenhouse gas contributions produced by the energy source used to generate electricity consumed by a mining operations Factor that affecting coal mine energy consumption, can be generated from many aspects such as operator practice, operating conditions and also equipment [2]. On the implementation, en- ergy consumption in mine also varies due to the variation of the mine topography, mine equipment characteristics and operational practices. The diesel or electricity are used for operating dump trucks, Author, year | Indones. J. Env. Man. Sus. 1 (1) 2017: xx - xx DOI: 10.26554/ijems.2018.2.1.7-108 excavators, shovels, draglines, crushers, conveyors and pumps. Based on benchmarking in Gondegaon opencast mine, input en- ergy profile for conventional opencast coal mine, Electricity has annual energy consumption of 8.203 MU equivalent with 98.760 GJ (36%) meanwhile Diesel has annual energy consumption of 5.019 MU equivalent with 179.195 GJ (64%) [3]. Electrical equipment (electrification) program in PT. Bukit Asam is a new mining method which previously domi- nated by fuel-based mining systems. Implementation of this pro- gram is done by implementing the main equipment of the elec- tric digging tool (shovel) and combined with fuel-based truck. Electrification is environmentally friendly program because it is proven to decrease energy consumption and decrease greenhouse gas emission. The calculation of this decrease is done by using comparison data of electrical-based mining equipment with fu- el-based mining equipment. • Electric Digging tool (Shovel) Equipment used in conducting excavation activities using Elec- tric Shovel PC 3000-6E • Transportation (Truck) The equipment used in carrying the hauling activity is Dumptruck BELAZ-75135. Figure 1. Factors affecting coal mine energy consumption [2] Figure 2. Shovel PC 3000 equipment. Specification of Electric Shovel PC 3000-6E: Type : Hydraulic Shovels Drive System : Electric Drive Output Power : 900 kW Bucket Capacity : 16,0 cum Crowd Force : 1100 kN Break-out Force : 1000 kN Boom : 6,0 m Stick : 4,3 m Figure 3. Belaz Truck Specification of Dumptruck BELAZ-75135: Nominal Payload Capacity : 110 metric ton : 120 Short ton Engine : Cummins K1500E Transmission : Electrical Transmission Ratio : Electric Speed Ratio up to 4726 Torque Nm Control System : Automatic Control System Top Speed (km/h) : 48 Front Brakes : Disk Brake Rear Brakes : Disk Brake, Resistor Brake Gross Vehicle (oper- ating Weight) : 230.100 kg Fuel Refill, ltr : 1900 Tires : 33.00 – 51 Figure 4. Electrification Mining Process Author, year | Indones. J. Env. Man. Sus. 1 (1) 2017: xx - xx DOI: 10.26554/ijems.2018.2.1.7-109 • Electrification Mining Process Electrification Mining Process is done by implementing the main equipment of the electric digging tool (shovel) and combined with fuel-based truck. RESULTS AND DISCUSSION Electrical equipment (Electrification) conducted by PTBA as an effort to maximize electrical energy from Mine mouth steam power plant in Tanjun Enim Mining Unit. Electrification is done by changing conventional mining method based on fuel into base- don electric energy. The mining method with the IPCC system has several ad- vantages and disadvantages, the following explanation as listed in Table 1. The results show that IPCC mining method with electrifica- tion has more advantages. Electrification succeeded in reducing operating costs by 40% caused by the fuel savings due to switch- ing to electricity. Table 2 there are cost efficiency in PC 3000 Electric of Rp 37,900,162,944 for 7 units Shovel Electric operates and decreas- ing oil usage as much as 29.187 liters per year equivalent with Rp. 1.208.904.636. Cost efficiency of usage belaz Truck 75135 amount Rp. 30,423,069,440 for 40 units operates and decreas- ing oil usageas much70,883 liters per year equivalents with Rp. 3,849,383,059,20. Table 2 show the complete calculation. Figure 5. Mining System changes from the old mining system in Pit Crusher & Conveyor (IPCC) system with Electric Equip- ment Table 1. IPCC system advantages and disadvantages analysis IPCC System (Shovel à Crusher à Conveyor àSP/SR/TLS) Advantages Disadvantages 1. Electricity cost (Rp./kWh) 40% less cheaper than fuel (Rp ./liter). 1. Limitations of flexibility by using conveyor crusher. 2. Reduce pollution of heavy equipment carbon emissions. 2. Investment cost is higher than shovel & truck. 3. Labor cost, maintenance cost and operating cost are relatively low and less than shovel & truck. 3. For the fully mobile type is resistant to weather, mean- whilesemi mobile is vulnera- ble to weather changes. 4. Can cover the mining distance is relatively fluid and flexible. 5. Suitable for Soft-hard rock and oversize type of material. Table 2. Calculation of Decreased Energy Consumption and Emission Reduction Decription Unit PC ELECTRIC PC DIESEL Liter / H - 184.00 KWH / H 436.00 - Jam jalan / Th 5212.00 5212.00 Number Of Unit unit 7 7 NCV Tj/liter - 0.000036 Fe CO2 (Diesel) Kg/Tj - 74100 Fe CO2 (Electric) Kg CO2 / kwh 0.749 - CO2 Emission Ton CO2e / Th 11,914.36 17,907.75 Emission Reductions Ton CO2e / Th Decription Unit PC ELECTRIC PC DIESEL Liter / H 58.70 75.00 KWH / H - - Jam jalan / Th 5212.00 5212.00 Jumlah Unit unit 40 40 NCV Tj/liter 0.000036 0.000036 Fe CO2 (Diesel) Kg/Tj 74100 74100 CO2 Emission Ton CO2e / Th 32,645.49 41,710.59 Emission Reductions Ton CO2e / Th Total Emission Reductions Ton CO2e / Th Information 5,993.39 9,065.10 15,058.49 Emisi CO2 (Diesel) = NCV x FE x Vol BBM Emisi CO2 (Electric) = FE x kwh NCV1 Diesel = 0,000036 Tj/liter FE2 CO2 (Diesel) = 74.100 Kg/Tj FE3 CO2 (Electric) = 0,749 Kg CO2/kwh FE = Emission Factor NCV = Heat Values 1. National Inventory Guidance Manual 2012, Book 1 Volume 1 Use and procurement of energy Table 2.2 2. National Inventory Guidance Manual 2012, Book 1 Volume 1 Use and procurement of energy Table 2.3 3. Letter of Emission Factor (DJ-ESDM), 2012 Energy Consumption Energy Consumption Author, year | Indones. J. Env. Man. Sus. 1 (1) 2017: xx - xx DOI: 10.26554/ijems.2018.2.1.7-1010 Electrification also reduced energy consumption by 333.861,74 Joule/Years. Decline in energy consumption is also followed by a decrease in greenhouse gas emissions of 15.058,49 Ton CO2/Year. Inefficiencies that affect electricity consumption in site can occur for many reasons. For example technical prob- lems in hauling road design that decreasing total productivity unit. CONCLUSION Comparison of operational costs for the use of electric shovel energy (PC3000-6E) with PC3000 diesel is Rp. 37,900,162,944 for 7 units Shovel Electric operates and decreased oil as much as 29.187 liters per year equivalent Rp. 1,208,904,636.80. Comparison of operational costs for the use of Belaz 75135 fuel (electric drive) with an equivalent dumptruck (HD785) using mechanical drive is Rp. 30,423,069,440 for 40 units of RT Belaz 75135 operates and decreased oil asmuch as 70,883 liters per year equivalent Rp.3,849,383,059,20. Total Energy savings from implementation of Electrification Program of 333.861.74 GJoule per year. Total Green House Gas emission reductions from implemen- tation of the Electrification Program of 15.058.49 Ton CO2e per year. There are opportunities to increasing efficiency by optimizing site conditions such as haul road design optimization to increase the productivity unit REFERENCE [1] Bleiwas, Estimates of Electricity Requirements for the Re- covery of Mineral Commodities, with Examples Applied to Sub-Saharan Africa, U.S. Geological Survey, 2011 [2] Awuah-Offei, K., Summers D., Hirsch C. J., Reducing En- ergy Consumption and Carbon Footprint through Improved Production Practices, Final Technical Report, Missouri Uni- versity of Science and Technology, 2010 [3] Indonesia Government, National Inventory Guidance Manual Book 1 Volume 1 Use and procurement of energy Table 2.2 (2012) [4] Indonesia Government, National Inventory Guidance Manual Book 1 Volume 1 Use and procurement of energy Table 2.3 (2012) [5] Letter of Emission Factor (DJ-ESDM), 2012