MechChem Africa July-August 2022

Hybrid and flexible power plants essential for supply security ⎪ PowerGen,PetroChem and Sustainable energy management ⎪ Wallace Manyara, Southern Africa Business Development Manager at Wärtsilä, writes about hybrid solutions that control and optimise energy storage and power generation.

cycle services are designed to increase ef ficiency, promote reliability and guarantee operational performance. Mining solutions An example of this is the work Wärtsilä has done with B2Gold, where it recently installed a hybrid solution at the off-grid Fekola Mine in Mal i . Enhanced by the Wärtsilä GEMS Digital Energy Platform, the system integrates, controls and op timises 17.3 MW/15.4 MWh of energy storage alongside a 30 MW solar PV plant, in addition to the mine’s existing 64 MW power generator. GEMS monitors, controls and optimises energy assets. It supports a variety of battery and power electronics to achieve optimal systemperformance. “What makes GEMS powerful is how it integrates and controls individual resources and entire fleets comprising energy storage, renew ables and traditional thermal generation. Using machine learning as well as historic and real-time data analytics to optimise the asset mix, GEMS enables customers to remotely monitor, operate, identify and diagnose equipment safely, reliably and flexibly,” says Manyara. The project has hybridised the energy supply of Fekola Mine using a combination of renewables, storage, a power generator and an energy management system. This has reduced the facility’s dependence on imported heavy fuel oil, saving operational and transportation costs, as well as reducing greenhouse gas (GHG) emissions. For Fekola, project payback is expected within four years, with projected long-term savings on mining operations including over 13.1-million ℓ of heavy fuel oil per year. The solution will also drive decarbonisation, with the mine’s GHG emissions expected to reduce by approximately 39-million kg of carbon dioxide emissions per year.

Mines inMali are required to work off-grid, given the infrastructure challenges that exist there. This project has illustrated the advantages of using energy storage in conjunction with smart energy manage ment controls to assist in moving towards achieving its decarbonisation objectives. The Wärtsilä hybrid solution ensures stable and uninterrupted power generation, resulting in economic and environmental benefits. Another example is Geita Gold Mine, situated in the Lake Victoria gold fields of north-western Tanzania, which is a flagship mine of AngloGold Ashanti. When Geita Gold Mine required a highly reliable power generation solution of 40 MW to support its growing operations, Wärtsilä provided a turnkey engineering, procurement and construction (EPC) solution followed by an operation andmaintenance contract (O&M) to ensure uninterrupted off-grid power. Managing SA’s energy crisis As well as being pushed to use cleaner fuel to progress on their decarbonisation jour ney, local mining companies in South Africa are having to respond to Eskom power sup ply challenges and are considering a number of alternatives through self-generation. Failure to secure power supply can mean a loss of millions in revenue. Furthermore, the escalating cost of Eskom electricity – of at least 10% per annum – is forcing mines to look for alternative resources they can manage more efficiently. The need to embrace clean power through solar PV, storage, and hydrogen mixed fuel sources could become critical for a mine’s operational success. “The time to begin to embrace these solutions and move forward into a new future of energy genera tion is now,” Wallace Manyara concludes. www.wartsila.com

W ith 100MWor fewer no lon ger requiring licensing, the power generation licensing regulations have opened the door for alternative ways of addressing the challenges Eskom faces. Apart from security of power supply, South African mining houses are under pressure to meet increasingly ambitious environmental and decarbonisation targets. Many mines believe that the ideal response is to install solar PV plants. While renew ables are the best option for rapid deploy ment and cheaper electricity, the sun will not always shine and PV plants have a level of intermittency, which needs the support of energy storage solutions, and in some instances, gas engines. Because a number of mines also work outside the normal hours of utilising a PV plant; a hybrid solution with gas engines and/or energy storage (ESS) will provide security of supply 24/7. ESS can also be used to store excess power generated by a PV plant during the day for use during peak hours when the grid tariff is higher, signifi cantly enhancing the value of investments made in solar technology. “As Wärtsilä, we believe in leading the transition towards a 100% renewable energy future. We help our customers to decarbonise by developing market-leading technologies. These cover future-fuel enabled balancing power plants, hybrid so lutions, energy storage and optimisation technology, including our GEMS energy management software platform. Our life

July-August 2022 • MechChem Africa ¦ 35