How-To: reduce energy consumption in mining
Without a doubt, mining projects consume a lot of energy. Trucks and excavators utilize diesel fuel during operations, electricity is used to grind ore and refine it, and coal is required for the smelting process. According to Mining Global, fossil fuels represent the largest portion of a mine’s total energy use at 35 percent, followed by electricity at 32 percent.
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While energy consumption represents a significant problem for mining companies, it also offers a significant opportunity if achieved correctly. The following tips can help mining companies reduce energy consumption, resulting in major savings, as well as reveal new strategies and technologies that can further reduce electrical usage.
The first step in reducing energy consumption is to develop a plan. According to Mining Global, a thorough plan should outline the company’s objectives while revealing short and long-term goals to achieve it. It should also establish a starting base in order to consistently evaluate and fine-tune actions.
The next step should be choosing a management system to streamline processes. These systematic tools have the ability to provide the following: real-time energy consumption; energy consumption forecasting based on specific parameters; establishing optimal energy consumption targets for each mine area; identifying and quantifying consumption above targets; identifying and analyzing root causes of over-consumption; reporting of over-consumption and changes in daily consumption; understanding energy drivers such as process variables linked to energy consumption; real-time calculation of sustainability Key Performance Indicators, such as kWh/t; providing validated data to justify future capital investments and/or process changes; creating energy models to forecast energy consumption and to determine energy targets.
Once up and running, the next step is to invest. Acquiring energy efficient products such as smart meters can help offset high levels of energy consumption during peak hours. Smart mining breakers are another potential product.
According to Mining Global, the real trick to reducing energy consumption is through continuous improvements. “By continually monitoring, tweaking and reporting new updates, companies can steadily improve system stability and unplanned downtime.”
In order to reduce energy consumption in mining projects, it’s vital that companies engage in ongoing, strategic actions and new technology.
Getting it done
The mining industry is littered with companies innovating new ideas to reduce energy usage. One example includes Alcoa’s RopeCon transport system at its Jamalco Operations in Jamaica. The company generates electricity while transporting bauxite ore downhill from the mine to the rail station. The system itself generates approximately 1,200 kW of braking (green) energy per hour, which is then used to power the mine. From 2007 to 2011, Alcoa saved $1.5 million in energy costs.
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South African gold producer Harmony Gold is an example of a mining company moving forward with renewable energy. The company has started building seven megawatt solar parks in Free State province with the goal of alleviating pressure on peak energy usage.
Glencore is another example of cutting the use of diesel and moving towards solar power. The commodity trader has installed wind turbine and energy storage facilities at its Raglan mine in the Nunavik region of northern Quebec in Canada.
Drax advances biomass strategy with Pinnacle acquisition
The Group’s enlarged supply chain will have access to 4.9 million tonnes of operational capacity from 2022. Of this total, 2.9 million tonnes are available for Drax’s self-supply requirements in 2022, which will rise to 3.4 million tonnes in 2027.
The £424 million acquisition of the Canadian biomass pellet producer supports Drax' ambition to be carbon negative by 2030, using bioenergy with carbon capture and storage (BECCS) and will make a "significant contribution" in the UK cutting emissions by 78% by 2035 (click here).
This summer Drax will undertake maintenance on its CfD(2) biomass unit, including a high-pressure turbine upgrade to reduce maintenance costs and improve thermal efficiency, contributing to lower generation costs for Drax Power Station.
In March, Drax secured Capacity Market agreements for its hydro and pumped storage assets worth around £10 million for delivery October 2024-September 2025.
The limitations on BECCS are not technology but supply, with every gigatonne of CO2 stored per year requiring approximately 30-40 million hectares of BECCS feedstock, according to the Global CCS Institute. Nonetheless, BECCS should be seen as an essential complement to the required, wide-scale deployment of CCS to meet climate change targets, it concludes.