MINE ELECTRIFICATION
Why Electrification?
Considering Future Carbon Emission Penalties/Taxes, when must my mine be Electrified to offset those, or is it more Cost effective to stay with Diesel Longer and Accumulate Carbon Credits from an Early Stage?
- With advances in BEV technology, will an Electric Mine Design work better for my mine irrespective of carbon taxes, and if so, what is the savings compared to Diesel?
- What is the Optimal Fleet Size and Type?
- How Does Electrification Affect Operations and Shift Schedules?
- What Electrical Infrastructure is Required, and Where?
- Can on site Renewable Energy Sustain the Mine’s Requirements?
Unique Solution: Full Scope, Integrated, Continuous Mine Simulation
How is ours different from traditional mine simulations?
Existing simulation platforms limited to solving models in Event-Based / Continuous fashion resulting in limitations in the scope of mine processes that can be simulated accurately, and the insights offered by the results. This is particularly a problem when comparing the full scope of a diesel vs electric mine, since both Event-Based and Continuous models need to be solved synchronously to produce accurate results over LOM to reduce risks. The integrated mine simulation solves Event-Based and Continuous models as a single synchronized model, producing highly accurate, day-to-day results for optimal schedules, costing and carbon footprint monitoring of an electric, hybrid or diesel version of a mine, or a combination thereof
Electrical Reticulation
Scope includes the electrical reticulation system to which all electrical power consumers will be connected. Simulated equipment includes Battery chargers and the electrical motors of the crushers, conveyors, hoist and ventilation fans. Other equipment are represented as consolidated loads exhibiting functional relationships with the production schedule. The electrical network is ultimately be connected to the national grid, with the mine’s power draw measured at that point.
Electrical Emissions
Models of power producers ranging from coal-fired to gas, nuclear, wind and solar power stations are included based on the actual power mix supplying the mine and relevant historic data on the supply ratio and availability of each supplier.
The models are connected to the grid, and allows exact calculation of the mine’s carbon footprint right up to the composition of each power stations’ emissions and each electric-powered device on the mine’s contribution to the overall carbon footprint.
Results from the Electrical Simulation
- Total energy usage.
- Energy usage for specific boards or equipment.
- Energy used by charging stations.
- Energy used by the ventilation system.
- Monitor the current through transformers or transmission lines.
- Ventilation system energy usage comparison when switching to an electric fleet.
- Live feedback on graphs monitor results as the simulation progresses.
Ventilation System
Reduction in power consumption by the ventilation system is simulated to the extent needed to calculate such a reduction accurately.
Diesel-powered vehicles introduce emissions / heat to the underground as they move through the mine. The ventilation system is tested to ensure removing heat / diesel particulates.
Power consumption of the system is usually calculated from functional relationships such as ventilation required per diesel engine based on the results from Vehicle Simulation as well as airflow / power usage per fan. However, in our simulation a more sophisticated continuous thermodynamic simulation is set up using fan characteristics, geometric volumes, and air flow paths providing more accurate results.
Control Systems
Switching of electrical and ventilation equipment is regulated by a control system, based on a typical control logic for electrical and ventilation equipment.
Vehicle Simulation
Diesel powered / hybrid and BEV mine vehicles and their movement will be simulated depending on a route network from the various ore interfaces to the ore handling systems.
Variable speeds, Fuel consumption and power usage / regeneration per vehicle type, depending on:
- Payload
- Gradient
SimMine Vehicle simulation interfaces with the Electrical simulation to allow:
- Synchronization / planning of vehicle runtimes vs battery life
- Charging times and power loads
- Interface with the Ventilation simulation determining how heat / emissions affects Ventilation design for Diesel/Hybrid/BEV options
Charging Stations
Impact of location and charge rate. Connected to electrical reticulation network. Battery swap vs fast charge.
Batteries
Battery discharge rate will correspond to the BEV’s power consumption. Battery regeneration on declines. Variable battery recharge levels.
Battery Electric Vehicle (BEV)
BEV power consumption parameters: Loading and tipping. Variable Speed (full and empty). Incline and decline gradients.
Diesel vs Electric Vehicle Simulation Results
All results are produced to calculate day-to-day development and production costs of Diesel vs Hybrid vs Electric over LOM. All results are produced to calculate day-to-day Scope 1 and 2 emissions for Diesel vs Hybrid vs Electric over LOM. Since all running hours and utilization of all vehicles are calculated on a day-to-day basis over the LOM, it allows in-time comparison of the costs associated with emissions (carbon taxes/credits) as well as development and production costs for a diesel/hybrid/electric version (or combination thereof) of the mine. This allows detailed cost calculation to be made to compare the financial feasibility of electrifying a mine or offsetting emissions via Carbon Credits, for a certain period of the full LOM. Fixed and running hour cost inputs for all vehicles are essential to simulate the above costs accurately.
Artificial Intelligence
Vehicles assigned to transport ore with a scheduling / dispatching algorithm. This scheduler is flexible enough to realistically handle variations in Stope Availability / Vehicle availability / Layout and Ore Handling System Constraints etc.
Each vehicle has equivalent of a driver: Dynamic management routine / Route Logic / Refuel or Recharging logic.
Fuel and Charging stations keeps track of how much of all consumptions.
Ore Production
Ore production is simulated using the Development / Production schedule from 1st Principle. Stochastic variation is superimposed on the schedule: Processing Times / Random Breakdowns, Production losses
Simulation Results from the integration of the development and production schedule provides results showing:
- Mine design constraints
- Layout change / optimization considerations
- Location / Capacity of infrastructure
- Potential Development Constraints
Ore Handling Systems
- Buffer Capacity Requirements to alleviate potential bottlenecks.
- Ore Handling System Sizing.
- Fleet Sizing.
- Considerations of energy supply since ore handling system a major sources of power consumption.
- Control logic used to regulate the behavior of the system.
Results from the Emissions Simulation
- CO2 emissions from electrical usage, total and for specific equipment.
- CO2 emissions produced by the electricity consumption of the ventilation system.
- CO2 produced by the battery chargers’ electricity consumption.
- Comparison between emissions for electrical vs diesel vehicles used.
- Total CO2 emissions split into scope 1 and 2.
- Reduction in scope 1 (and potential increase in scope 2) and total emissions when switching to an electric fleet.
- Live simulation feedback on graphs, stop and restart the simulation at any time with new parameters.
- Proposed Start and Stop logic for underground ventilation fans.
Typical Conclusions
- Preliminary results point to Electrification being the best financial decision for underground mine layouts considered so far
- Significant reduction of scope 1 emissions and only minimal increase in scope 2 emissions (electrical energy usage) due to considerable savings on ventilation energy
- Maintenance cost left out of the equation due to insufficient historic data, i.e. assuming electrical vehicles maintenance will be similar to diesel vehicles
- Main saving is on diesel cost
- Saving on potential/future carbon taxes also significant, but not the main reason to go electric
