Knocking down power barriers

MELODIE MICHEL Reporter, Energy and Mines

As hybrid power systems for mines become more and more widespread, tailored and reliable, Energy and Mines speaks to Mark Kennedy, Business Development Manager at Wärtsilä, about the remaining barriers for decarbonizing mine power.

Energy and Mines: What has changed in the last 6 months in terms of the decarbonization strategies of mines?

Mark Kennedy: We have seen more and more mines studying and implementing strategies to add renewables and energy storage. This is largely driven by the increasingly favourable economics of clean technologies. A good example is energy storage where battery prices continue to drop year on year. Other factors contributing to favourable economics for clean energy are increasing carbon taxes and government legislation.

E&M: Have you noticed any impacts of the global pandemic on the operational energy strategies and decarbonization goals of mining operators?

MK: From Wärtsilä’s perspective the global pandemic has necessitated some changes in the way we do business. However, thankfully most of our projects and supply chains have not been adversely impacted by the pandemic. The main challenges related to the pandemic for our projects have been around travel restrictions and quarantine requirements. This has made getting people to certain sites quite a challenge. However, on the equipment side, we have been able to manufacture and source equipment on normal schedules and timelines.

E&M: Which disruptive technologies do you think will likely be the most effective in terms of displacing diesel for mines?

MK: What we are seeing is that renewable power, combined with batteries (energy storage) is the most effective way to reduce diesel consumption at mine sites. The type of renewable power differs greatly from country to country. We are also seeing some cases where natural gas is replacing diesel consumption, mainly through LNG. We have seen strong growth in our Dual Fuel engines which have the capability to run on liquid fuel (eg diesel) and also natural gas.

E&M: What are the main challenges of trying to lower emissions from power while maintaining production targets?

MK: The main challenge for miners is reliability and quality of power. It is one thing to have access to renewable energy but the system needs to be reliable and ensure that production is not impacted. We believe the key to ensuring this is having an energy management system (EMS) that can incorporate renewable power with thermal power and maintain reliability at all times. This is why Wärtsilä has been very focused on GEMS, which is Wärtsilä’s Greensmith Energy Management System. This state-of-the-art software manages the energy at the site, incorporating thermal, batteries, renewables in an optimal way — to ensure a reliable system that optimizes the lowest use cost of energy.

E&M: Wärtsilä has been involved in landmark renewable energy and storage projects for mines including Resolute, B2Gold, and IAMGOLD — can you tell us about the lessons learned from those projects?

MK: The one consistent lesson is that hybrid-powered mines result in significant savings and emissions reductions for the owner. If we take the B2Gold project, the hybrid concept is expected to reduce CO2 emissions by almost 18 tonnes annually and cut processing costs by 7%. At that mine in Mali, Wärtsilä is designing a cutting-edge 17.3 MW/15.4 MWh energy storage system with GEMS energy management technology. GEMS will not only control the energy storage system but also integrate a new 30 MW solar plant under construction at the mine. The GEMS software platform interacts with and manages every part of the system to optimize performance, essentially operating as a conductor running a symphony.

E&M: How is the approach changing in terms of mines’ investments in renewables and low-carbon technologies?

MK: One of the noticeable changes is how mines are embracing energy storage. One of the many benefits of energy storage is that it converts an intermittent source of power, such as solar and wind, into a predictable one. Not only does this allow the use of renewable resources to be maximized, but it also allows a reduction in the spinning reserve — the amount of overproduction of electricity by the generators that is needed to ensure the power supply is maintained in case of a generator going down or a dip in solar production. In this way, having a “renewable battery” removes the uncertainty of solar and wind and allows the conventional part of the hybrid plant to run more efficiently.

E&M: What are the remaining barriers for integrating renewable energy and storage solutions?

MK: We do not see any barriers anymore. The prices have come down to a competitive level, the technology is proven and most importantly we have the energy management systems such as GEMS to ensure reliability.

E&M: What do you think would assist mines in addressing the challenges of low-carbon energy solutions?

MK: One of the important ways to assist mines is to run simulations and modelling of the power system to see if the project makes sense. Wärtsilä can help with this type of analysis.

Mark Kennedy can be contacted at mark.kennedy@wartsila.com