Tag Archives: B2Gold

Suntrace, BayWa re, B2Gold commission ‘world’s largest’ off-grid solar-battery system

Suntrace GmbH and BayWa re, together with B2Gold, have completed commissioning of what they say is the world’s largest off-grid solar-battery hybrid system for the mining industry at the Fekola gold mine in Mali.

The solar-battery hybrid plant was integrated and commissioned successfully with the existing power plant operation, with the solar plant on course to be 100% complete by the end of June.

Hybrid projects such as this, which combine solar energy with conventional energy generation and battery storage, are an effective way to provide reliable power supply day and night in off-grid areas, Suntrace says. “Ideally suited to their needs, B2Gold approved the hybrid project for implementation in July 2019, following completion of preliminary studies by Suntrace and BayWa re.”

The Fekola gold mine operates 24-hours a day. During the daytime, the new 30 MW solar plant allows three out of six heavy fuel oil generators to be shut down; the energy production of the residual three generators could also be significantly reduced. The 15.4 MWh battery storage compensates for energy generation fluctuations and assures a reliable operation, which allows up to 75% of the electricity demand of the gold mine to be covered by renewable energy during the daytime, Suntrace said.

Dennis Stansbury, Senior Vice President at B2Gold, said: “Suntrace and BayWa re have played a vital role in our work towards more sustainable production at Fekola. The implementation of a solar-battery hybrid system was an obvious choice to help achieve this, not only for its environmental credentials, but also its economic viability. This is a landmark project which we expect to pave the way for more sustainable power generation within the mining industry in West Africa.”

The integration of the solar power plant with the battery system will ensure safe and reliable power, saving 13.1 million litres of heavy fuel oil a year.

Martin Schlecht, COO of Suntrace, said: “We are very proud that B2Gold has entrusted Suntrace, together with BayWa re as engineering and procurement contractor, to support the development and implementation of this innovative project. Thanks to excellent team work with B2Gold and BayWa re, we were able to manage the completion despite the global challenges that the COVID-19 pandemic imposed on all of us. We are proud to jointly deliver a functioning project, well integrated with the mining operations, which reduces CO2 emissions from power generation for the Fekola mine by roughly 20%.”

The photovoltaic-battery system will help to reduce CO2 emissions by 39 000 t/y, according to the company.

Thorsten Althaus, Project Manager at BayWa re, added: “Integrating such a large amount of solar into a small, isolated grid safely and reliably has been a major technical challenge and required the use of battery storage as well as a tailor-made control system. This was conceptualised in the early stages of the project and we ensured that our vision was implemented accordingly by the suppliers. It is extremely rewarding to see how well this solution performs in reality and shows that the technology works and is just waiting to be applied on further projects.”

B2Gold weighs use of dual fuel haul trucks at Kiaka project

B2Gold’s strong growth path in Africa looks like continuing into future years after the company laid out preliminary plans to develop a mine in Burkina Faso that could use on-site hybrid power in addition to dual fuel haul trucks burning a mix of diesel fuel and LNG.

The Vancouver-based miner reported record total production in 2020 of 1.04 Moz of gold, with its Fekola (Mali) and Ojikoto (Namibia) mines contributing some 790,559 oz. It is guiding for 970,000- 1.03 Moz of gold in 2021.

In announcing these results, the company also provided an update on its Kiaka gold project in Burkina Faso.

This project, which B2Gold owns 81% of, currently hosts 4.25 Moz of indicated resources on a 100% basis at an average grade of 0.95 g/t Au. It also comes with 900,000 oz of inferred resources at 0.99 g/t.

The company is currently updating the existing feasibility study for the Kiaka project, reflecting, it says, the potential for improved economics resulting from lower fuel prices, alternative power options and a higher gold price.

A mineral resource model using additional drill results and revised model interpretations was completed in December, with the study set to leverage the new resource and several new concepts to reduce costs. Included among these new concepts is a plan to use a liquid natural gas (LNG) hybrid power plant combined with solar power, and dual fuel haul trucks that burn a mix of diesel fuel and LNG.

A larger processing plant size of 12 Mt/y is also being considered for this updated feasibility study, it said.

B2Gold expects to have an internal decision document completed by the end of March, with an updated feasibility study completed by the end of June.

Optimising energy management at B2Gold’s Fekola mine

The delivery of a cutting-edge 17 MW/15 MWh energy storage platform and Wärtsilä’s advanced GEMS system is optimising energy management at B2Gold’s Fekola gold in Mali, Luke Witmer* writes.

Since B2Gold first acquired the Fekola gold mine, located in a remote corner of southwest Mali, exploration studies revealed the deposits to be almost double the initial estimates.

A recent site expansion has just been completed, and while the existing power units provide enough power to support the increase in production, the company sought to reduce its energy costs, cut greenhouse gas emissions, and increase power reliability.

The addition of a 35 MWp solar photovoltaic (PV) plant and 17 MW/15 MWh of energy storage to the existing 64 MW thermal engine plant was decided. This new energy mix is anticipated to save over 13 million litres of fuel, reduce carbon emissions by 39,000 t/y, and generate a payback in just over four years.

Such an elaborate hybrid configuration needs a powerful brain to deliver on all its potential: Wärtsilä’s GEMS, an advanced energy management system, has been set up to control the energy across the fleet of power sources, thermal, renewable, and battery storage. The integration, control, and optimisation capabilities provided by GEMS allow the thermal units to be run at the most efficient rate and enable the battery storage to handle the large load step changes and volatility of the solar PV generation assets.

Integrated hybrid energy solution

In the context of the Fekola mine, which is an off-grid electrical island, the battery is performing a lot of different services simultaneously, including frequency response, voltage support, shifting solar energy, and providing spinning reserves. The energy load is very flat, with a steady consumption rate around 40 MW as the mining equipment is operating consistently, 24/7. However, if an engine trips offline and fails, the battery serves as an emergency backstop. The controls reserve enough battery energy capacity to fill the power gap for the time it takes to get another engine started, and the software inside each inverter enables the battery to respond instantaneously to any frequency deviation.

The reciprocating engines operate most efficiently at 85-90% of their capacity: this is their ‘sweet spot’. But if there is a sudden spike in demand, if a little more power is needed, or if mining equipment is coming online, then another engine needs to be run to meet the extra load.

With the battery providing spinning reserves, the engines can be kept running at their sweet spot, reducing the overall cost per kilowatt hour. Moreover, with the solar plant providing power during the day, three to four engines can be shut down over this period, providing a quiet time to carry out preventive maintenance. This really helps the maintenance cycle, ensuring that the engines operate in a more efficient manner.

Solar PV volatility can be intense. On a bright day with puffy clouds passing by, a solar farm of this size can easily see ramps of 25 MW over a couple of minutes. This requires intelligent controls, dynamically checking the amount of solar that can be let into the grid without causing an issue for the engine loadings or without overloading the battery.

Conducting the orchestra

The GEMS intelligent software provides the optimisation layer that controls all the power sources to ensure that they work together in harmony. The user interface (UI) gives access to all the data and presents it in a user-friendly way. Accessible remotely, all operations are simulated on a digital twin in the cloud to verify the system controls and simulate the most efficient operating scenarios to lower the cost of energy.

This is an important software feature, both during and after commissioning as it allows operators to train on the platform ahead of time and familiarise themselves with the automated controls and dynamic curtailment of renewables. The UI provides the forecast for renewables and the battery charge status at any given moment, it can provide push email or phone notifications for alerts; telling operators when to turn off an engine and when to turn it back on.

The software is constantly analysing the data and running the math to solve the economic dispatch requirements and unit commitment constraints to ensure grid reliability and high engine efficiency. Load forecasting integrates the different trends and patterns that are detectable in historic data as well as satellite based solar forecasting to provide a holistic approach to dispatching power. The Fekola site has a sky imager, or cloud tracking camera with a fisheye lens, that provides solar forecasts for the next half hour in high temporal resolution.

To ensure that operators really understand the platform, and have visibility over the advanced controls, the UI provides probability distributions of the solar forecast. Tracking the forecast errors enables operators to see whether the solar is overproducing or underproducing what the forecast was expecting at the time and provides visibility to the operators on the key performance indicators. This feedback is an important part of the machine/human interface and provides operators with insight if an engine is required to be turned on at short notice.

Automated curtailment enables the optimisation of the system providing a reactivity that people cannot match. By continually monitoring the engine loadings and battery, the system is ready to clamp down on solar if it gets too volatile or exceeds some spinning reserve requirement. For example, if a large, unexpected cloud arrives, the battery is dispatched to fill the gap while the engines ramp up. Once the cloud disappears, however, the engines remain committed to operating for a few hours, and the solar power is transferred to recharge the battery.

Over time, as load patterns shift, the load forecasting algorithm will also be dynamically updating to match the changing realities of the load. As mining equipment hits layers of harder rock, increasing the power load, the system will adjust and dispatch the engines accordingly.

The new gold standard

The Fekola mine project incorporates the largest off-grid hybrid power solution in the world, demonstrating the growing case for clean energy and its sustainable and economic potential for mines in Africa and beyond.

As the cost of batteries and solar panels continues to become more competitive, hybrid solutions are proving to be a realistic and effective means for increasing energy reliability and lowering operating costs in any context, thus freeing up resources to improve the human condition; whether through cheaper materials and gainful employment, or by providing broader access to reliable electricity for healthcare, education, and improved quality of life.

*This piece was written by Luke Witmer, General Manager, Data Science, Wärtsilä Energy Storage and Optimization

Booyco Electronics to provide Otjikoto gold mine with ‘true collision avoidance system’

Proximity detection specialist Booyco Electronics says it is equipping 19 mechanised mining machines with its latest Booyco CXS proximity detection solution to enhance safety during the development phase of underground operations at B2Gold’s Otjikoto gold mine, in Namibia.

According to Anton Lourens, Booyco Electronics CEO, the order was placed by Murray & Roberts Cementation, one of the contractors establishing the underground stoping horizon for the Wolfshag zone at Otjikoto mine.

The contract also includes sensing devices for 120 underground personnel on the operation, which will be included in the employee’s cap lamp to provide an alarm.

“Our equipment will help achieve the highest level of safety by mitigating the risk of collisions between pedestrians and vehicles, and between vehicles, on this project,” Lourens says. “The installation of our CXS units is in line with the commitment by the mine and the contractor to zero harm in the workplace.”

The Cementation Lewcor JV contract will take 28 months. Lewcor Mining is a Namibian company with extensive mining experience in that country. The contract includes a decline of 5 m wide by 5.5 m high being driven to the orebody from a portal in one of Otjikoto’s depleted open pits. The operation will be highly mechanised, with equipment including drill rigs, dump trucks, LHDs and utility vehicles, as well as shotcreting and ancillary equipment.

Lourens highlights that Booyco Electronics’ latest generation CXS system is a comprehensive and integrated proximity detection solution, taking a step beyond being just a warning system to become a “true collision avoidance system”.

He added: “The CXS system on this project will deliver Level 7 and Level 8 capability in terms of the Earth Moving Equipment Safety Roundtable (EMESRT) and can also accommodate Level 9. Although there is not yet a legal requirement for collision avoidance systems in Namibia, our customer and the mine adopt a global best practice approach to all aspects of safety in mining operations.”

With the mine’s location more than 300 km north of Windhoek, it is important the equipment is robust and reliable to ensure maximum uptime, according to Lourens.

“To ensure that the equipment performs optimally, we have trained the customers’ artisans on how to look after it,” he said. “A qualified serviceman from Booyco Electronics will also visit the site regularly to audit performance, assess the equipment and conduct any necessary maintenance.”

Booyco Electronics’ home-grown technology has seen wide take-up in underground operations – both hard rock and coal – as well as in the open-cast environment, plants and warehouses, the company says. It now has a footprint of over 100 mining customers in South Africa, with this Namibia project part of a gradual expansion into other countries in Southern Africa.

Lourens says the use of collision avoidance systems is likely to keep increasing, as more miners adopt the EMESRT guidelines.

He concluded: “The International Council on Mining and Metals (ICMM) is also an important stakeholder in this process. The ICMM highlights that transport and mobile equipment accidents were highest cause of fatalities at their members’ operations in 2018, accounting for 30% of fatalities.”

B2Gold’s Fekola mine expansion starts up ahead of schedule

B2Gold Corp has successful commissioned the mill expansion at the Fekola mine, in Mali, to 7.5 Mt/y, around one month ahead of the scheduled completion date of September 30, 2020.

The company has completed all major construction activities associated with the Fekola mill expansion, as well as successful execution of a process performance test to compare with design expectations, it said.

Four days after start-up, a five-day mill performance test was conducted from August 26 to August 30, 2020. The results of the performance test exceeded design in throughput, gold recovery, grind and availability over the period. The minor, outstanding construction work is expected to be completed by mid-September 2020, it said.

The expansion has seen the company expand the mining fleet (adding excavators, trucks, and drill rigs); bolster the mill with cyclone clusters, leach and CIP tanks; and complete a double lift on the tailings storage facility.

This has already had an impact on the mine’s core metrics. In the first half of the year, Fekola produced 311,435 oz of gold, 7% above budget and 39% higher than the first half of 2019.

B2Gold acquired Fekola through a merger with Papillon Resources in October 2014, with the company completing construction of the Fekola mill and commencing ore processing more than three months ahead of the original construction schedule and on budget, in September 2017.

The first gold pour at Fekola took place on October 7, 2017. Within only 60 days from start-up, the mine achieved commercial production on November 30, 2017, one month ahead of the revised schedule and four months ahead of the original schedule.

MacLean Engineering up to the Africa mining challenge

MacLean Engineering’s investment in Africa is paying off, with multiple production support vehicle sales recently secured on the back of an increased presence in South Africa.

Having last month bolstered its largest single fleet in Africa to 11 vehicles at the Kibali gold mine, in the Democratic Republic of Congo, the company is now busy assembling equipment for delivery at an underground mine in Namibia, while making manufacturing and delivery plans for a successful tender for five units that will head to a underground gold mine in Mali.

John-Paul Theunissen, MacLean’s General Manager for Africa, says recent sales could be put down to the company boosting its manufacturing and service capacity on the continent close to two years ago.

“We are now manufacturing for Africa out of South Africa,” he told IM. “Towards the end of 2018/beginning of 2019, we commissioned another 900 sq.m of manufacturing space at our South Africa facility. This means we now have 1,000 sq.m of workshop and assembly space.”

The Free State facility, the first international branch MacLean set up back in the 1990s, also offers maintenance and service support.

These attributes, plus the ability to access MacLean engineers across the globe for equipment troubleshooting, have allowed Africa-based mining companies to get comfortable with the Canada-based brand, according to Theunissen.

“We have really started to build momentum in Africa, increasing the level of service and support closer to home,” he said.

“It is this local aspect that really sells fleets, as opposed to individual machines.”

MacLean now has 1,000 sq.m of workshop and assembly space, Theunissen says

This increased local offering has arrived at just the right time.

While the stricter lockdown measures in South Africa have been lifted – the country has moved from Level 5 to Level 3, allowing mines to return to full capacity (with COVID-safe procedures in place) – companies procuring equipment for Africa are conscious intercontinental deliveries could face upheaval again if a ‘second wave’ of COVID-19 hits.

Some mining companies influenced by recent lockdowns are also making longer-term pledges to adjust their supply chains to take advantage of local expertise, at the same time reducing potential risks that come with buying machines and solutions from overseas suppliers.

This recently enlarged presence in Africa could see MacLean benefit from such moves.

Recent orders

The latest orders Theunissen mentioned could reflect this reality.

In securing a contract to supply three MacLean 3-Series Cassette Trucks (CS3) and four cassettes to the Murray & Roberts Cementation and Lewcor Mining joint venture set to establish the underground stoping horizon at the Wolfshag zone at B2Gold’s Otjikoto mine, in Namibia, the company achieved several ‘firsts’, he said.

“It’s a new customer, Murray & Roberts; a new country, Namibia; and a new miner, B2Gold,” he said.

These units will be assembled in South Africa – another MacLean first – and are due to be delivered to the mine by the end of the last quarter of the year, according to Theunissen.

And, as mentioned before, the company recently bolstered the fleet at the Barrick Gold/AngloGold Ashanti majority owned Kibali gold mine in the DRC.

The latest piece of equipment for the mine – which arrived at the end of July – was one of the company’s personnel carriers.

This adds to the three EC3 Emulsion Chargers, a WS3 Water Sprayer, a FL3 Fuel Lube Truck, and a BT3 Boom Truck – all from MacLean’s trusted Mine-Mate™ Series – that Byrnecut, the original mining contractor at Kibali, brought in from 2013 onwards.

When the Kibali mining model changed to ‘owner-operator’ under the management of Randgold (now Barrick), the fleet got bigger, with the miner adding four new rigs: another EC3, another BT3, an SL3 Scissor Lift with pipe handler attachment, and a TM2 Mobile Concrete Mixer.

MacLean says its expanding presence at Kibali, from the development phase all the way back in 2013 up to achieving record production numbers in 2019 and 2020, illustrates the “MacLean Advantage in action”.

It explained: “MacLean’s dedicated team in South Africa has worked closely with mine management and operators to provide the training, maintenance and support needed to keep Kibali running smoothly. With operations forecast to continue at Kibali through 2036, MacLean looks forward to providing dependable support for years to come.”

Tech take-up

Mines like Kibali – one of the most technologically advanced in Africa – are gradually becoming more and more automated in an effort to increase productivity and safety.

Already one of the world’s most highly automated underground gold mines, Kibali’s backbone is Sandvik’s AutoMine Multi Fleet system, supervised on surface by a single operator. This system, in a world first, allows a fleet of up to five LHDs to be operated autonomously, 750 m below the surface, within the same 6 m x 6 m production drive while using designated passing bays to maintain traffic flow, Barrick says. A similar system is used in the production levels to feed the ore passes, according to the company.

While MacLean’s production support vehicles often interact with these autonomous loaders, for the time being they are still manned by operators.

This is set to change into the future, according to Theunissen.

“The Advanced Vehicle Technology Team (AVT) in Canada is moving into the automation space,” he said. “We’re looking to integrate our own digitalised systems into those of OEMs such as Sandvik and Epiroc to ensure fully interoperable autonomous operation.”

Within the AVT, the Advanced Vehicle Technology group embedded at the MacLean Research and Demonstration Facility, in Sudbury, Ontario (pictured below), has over 20 engineering staff working on remotely controlled to fully autonomous vehicle operation, using radar, LiDAR, and vehicle monitoring technology, according to MacLean.

This team has already come up with vehicle telemetry hardware and software, and virtual reality training tools. It is also transitioning to a cloud-based platform for documentation, parts ordering, and training content called Documoto.

The Advanced Vehicle Technology group is embedded at the MacLean Research and Demonstration Facility, in Sudbury, Ontario (photo: James Hodgins)

While these technology developments will, in the future, underwrite the company’s transition to offering machines capable of fully autonomous operation, MacLean is already at the front of the pack when it comes to facilitating the industry’s electrification movement.

In Canada, it has more than 30 battery electric mining vehicles (BEVs) working underground – at 10 mine sites, across four provinces, with more than 50,000 operating hours amassed.

While Africa as a whole might not yet have the energy infrastructure in place to fully leverage these ‘green’ BEVs – many mines remain off grid and reliant on diesel power – Theunissen has seen grid-connected miners in South Africa show interest in taking on these machines.

“In South Africa there is already appetite for BEVs,” he said. “We see it coming through in the RFIs (request for information) we get on projects.”

MacLean has an advantage over some of its competitors when it comes to converting these RFIs into sales.

Not only has it got thousands of operating hours under its belt, it also has engineers in place that can calculate the total cost of ownership savings a specific mine will achieve should they bring BEVs into their fleets. Due to the increase in upfront cost currently seen when comparing diesel- with battery-powered vehicles, this type of analysis is crucial to securing orders.

“We can show them how the machine will fit into the mining cycle and provide in-house calculations on ventilation and mine design savings,” Theunissen said. “This helps assist end users when it comes to long-term decision making for the mine.”

For countries in Africa to get on board the electrification train like those mines in Canada have, Theunissen thinks governments will need to introduce incentives for mines to change their energy inputs and adopt BEVs.

Should this happen, MacLean will be equipped both within the continent and internationally to take on that challenge.

B2Gold to soak up solar power at Fekola gold mine

B2Gold, in its June quarter results, has provided an update on its plans to install a solar plant at its Fekola gold mine in Mali.

The company said it completed a preliminary study to evaluate the technical and economic viability of adding a solar plant to the site, during the quarter, with the results indicating it was a very “solid project” and that a plant of around 30 MW of solar generating capacity with a significant battery storage component would provide the best economic result.

A second study has now been completed to establish the detailed capital and operating cost analysis for the project. Results indicated that a solar plant can provide significant operating cost reductions (estimated to reduce processing costs by some 7%), with the project approved by the B2Gold Board in the June quarter.

The company said: “The Fekola Solar Plant will be one of the largest off-grid hybrid solar/heavy fuel oil (HFO) plants in the world.

“It is expected that it will allow for three HFO generators to be shut down during daylight hours, which will save about 13.1 million litres of HFO per year, at a capital cost of approximately $38 million, of which $20 million is expected to be incurred in 2019, with the balance in 2020.”

The solar plant is scheduled for completion in August 2020 and has a four-year payback, B2Gold said.

At Fekola, the company is currently weighing up an expansion that could see the life of mine could extend into 2030, including significant estimated increases in average annual gold production to over 550,000 oz/y during the five-year period 2020-2024 and over 400,000 oz/y over the life of mine (2019-2030).

Back in May 2018, B2Gold celebrated the official opening of the Otjikoto gold mine solar plant, in Namibia, one of the first fully autonomous hybrid plants in the world.

At the time, B2Gold said it would allow the company to significantly reduce fuel consumption and greenhouse gas emissions from the site’s current 24 MW HFO power plant. The shift to a HFO solar hybrid plant was, at that point, expected to reduce Otjikoto’s HFO consumption by around 2.3 million litres and reduce associated power generation fuel costs by approximately 10% in 2018.

In the company’s 2018 results, B2Gold said the plant was now providing close to 13% of the electricity consumed on site and the plant had achieved its expected HFO consumption and power generation fuel cost results.

B2Gold weighs up in-pit crushing and conveying as Fekola mine expansion economics stack up

B2Gold’s plan to expand its Fekola gold mine, in Mali, by 1.5 Mt/y could see an up to $56 million investment in additional excavators, trucks, drills, support equipment and wheel loaders, according to the latest project economic study.

The expansion study preliminary economic analysis showed the company could increase throughput to 7.5 Mt/y, from the current 6 Mt/y base rate, by injecting just under $50 million over a period of some 18 months for processing expansion and upgrades.

As currently envisioned, the processing upgrade would focus on increased ball mill power, with upgrades to other components including a new cyclone classification system, pebble crushers, and additional leach capacity to support the higher throughput and increase operability.

“Critical path items include ball mill motors and the lime slaker, both of which will be commissioned in Q3 (September quarter) 2020,” B2Gold said.

“In parallel with the expansion, B2Gold is studying the addition of a solar power plant, which would reduce operating costs and greenhouse gas emissions. The current on-site power plant has sufficient capacity to support the expanded processing throughput, with or without the solar plant.”

On top of this, the company would need to invest in its mining fleet.

The current mining fleet consists of four Caterpillar 6020B excavators with haul trucks, drills, and support equipment to match, and mines an average of 36 Mt/y. The Whittle study results currently indicate mining production rates ranging from 54 Mt/y to 76 Mt/y are optimal to support the expanded processing rates over the life of mine and optimise head grade during the period 2020-2024.

B2Gold said: “Increased production will be achieved with the addition of two to four excavators with corresponding trucks, drills, and support equipment. Large front-end loaders would also be included to maintain fleet flexibility.

“Mine fleet expansion timing and scale will be optimised during Q2 (June quarter) 2019 and will generally be equipment loan/lease financed over a five-year period. The study has included $28 million for expansion to 54 Mt/y and an additional $28 million (for a total of $56 million) to go to 76 Mt/y.

“In parallel with the Whittle study, B2Gold is reviewing in-pit crushing and conveying as a means to reduce operating costs and potentially implement tailings and waste co-disposal at the Fekola mine.”

The expansion study estimated optimised that the life of mine could extend into 2030, including significant estimated increases in average annual gold production to over 550,000 oz/y during the five-year period 2020-2024 and over 400,000 oz/y over the life of mine (2019-2030).

This would see an increase in project net present value of approximately $500 million versus the comparable amounts in the company’s latest AIF mineral reserve life of mine model based on a $1,300/oz gold price and a discount rate of 5%.

Solar hybrid power plant pays off for B2Gold at Otjikoto in Namibia

B2Gold has provided an update on the solar power plant working at its Otjikoto gold mine, in Namibia, in its 2018 financial results, confirming that the installation is making savings when it comes to heavy fuel oil (HFO) use and power generation costs.

On May 29, the company celebrated the official opening of the solar plant, one of the first fully-autonomous hybrid plants in the world.

At the time, B2Gold said it would allow the company to significantly reduce fuel consumption and greenhouse gas emissions from the site’s current 24 MW HFO power plant. The shift to an HFO solar hybrid plant was, at that point, expected to reduce Otjikoto’s HFO consumption by approximately 2.3 million litres and reduce associated power generation fuel costs by approximately 10% in 2018.

B2Gold selected Caterpillar and Cat® dealer Barloworld for the 7 MW solar power solution. The full system included Cat photovoltaic solar modules and the Cat microgrid master controller.

In the company’s 2018 results, B2Gold said the plant was now providing approximately 13% of the electricity consumed on site.

And, the plant had also achieved its expected HFO consumption and power generation fuel cost results: “Changing the power plant to an HFO solar hybrid plant reduced Otjikoto’s HFO consumption by approximately 2.4 million litres and reduced associated power generation fuel costs by approximately 10% in 2018,” B2Gold said.

Renewable energy use can bring savings to Africa mining sector, report claims

THEnergy and Voltalia’s latest report on the use of renewable energy in the Africa mining sector says the industry can realise significant cost savings when employing these power solutions.

The authors said the mining sector has shifted from phase one – where the focus of renewable power adoption was on integrating and testing out the reliability of these solutions – to phase two – where potential cost savings are being considered.

“In the last few years, more and more mining companies have adopted wind and solar systems to reduce their energy costs at remote off-grid mines,” THEnergy and Voltalia said. “In this first phase, the initial focus was on the integration capabilities as miners were afraid that adding intermittent renewables such as solar and wind could affect the reliability of power supply and even lead to production losses.”

In various microgrid applications, renewables combined with diesel, heavy fuel oil (HFO), or gas have proven to provide reliable power supply to remote mines, according to the two firms.

“For almost all mines, the integration of renewables will have a positive impact on their energy cost position. Mining companies do not have to invest their own money; independent power providers (IPPs) invest in the renewable energy infrastructure and sell electricity to mines through power purchase agreements (PPAs),” THEnergy and Voltalia explained.

Thomas Hillig, Managing Director of THEnergy, a consultancy focused on microgrids/mini-grids and off-grid renewable energy, said this second market phase is characterised by price competition.

“With the support of a leading renewable energy player, the new report analyses how IPPs can offer extremely competitive PPAs to remote miners,” he said.

Large IPPs take advantage of economies of scale on components for solar and wind power plants not only for remote mining projects but also for much bigger grid-connected plants, the two firms said.

“Market leaders have managed to optimise the planning and construction processes substantially. However, conducting projects in remote locations, especially in Africa, requires an extended experience,” they added. Among the challenges of undertaking projects in Africa is financing, which requires relationships with local and international banks, according to THEnergy and Voltalia.

“Cost optimisation does not necessarily mean minimising capital expenditure but rather focusing on the total lifetime of the project and including operation and maintenance. It is also important to take the interplay of the different energy sources into consideration. Not every kWh of solar and wind energy generated means equivalent fossil fuel savings. When gensets run at suboptimal loads, they lose efficiency and require additional maintenance,” the two firms said.

Alexis Goybet, Head of Hybrid Solutions at Voltalia, a player in the renewable energy sector, said his company has much experience in renewable energy projects, including solar-diesel hybrid microgrids, projects in remote locations and in developing countries.

“Our experience adds up to our economies of scale in procurement and translates into significant overall cost-reductions in the range of 20-30% in comparison to new market entrants,” he said.

These overall cost reductions will make solar and wind energy extremely attractive for many mines, according to the two firms, with the number of remote mines adding renewables to diesel, HFO or gas expected to grow quickly all over Africa.

There are already several mining companies that have made – or are planning to make – this transition in Africa, as can be seen by the map above (credit: THEnergy, Voltalia). This includes Resolute Mining and its Syama underground gold mine in Mali, Newmont Mining and its Akyem gold mine in Ghana and B2Gold and its Otjikoto operation in Namibia.

In the past month alone, Barrick Gold and GoviEx Uranium have also stated plans to use hybrid solutions at their Loulo and Madaouela assets, respectively.