Powering remote mines

Mohammad Sedighy,  Hatch‘s Principal Consultant, Electrotechnologies, notes the global estimate of 1.7 billion people living off-grid without any links to power utility systems of transmission lines and power stations. “In the developing world, a large number of such communities lack access to electricity altogether. And in some others, the electricity is generated locally. But the issue of access to power is not limited to developing countries. In Canada alone, there are nearly 300 remote communities that fit the description.

“For these communities, being off-grid is often not a choice. They are often too small, too remote, or surrounded by water, making grid connection infrastructure uneconomical to build. These challenges don’t just impact remote residential communities. There are many off-grid industrial facilities, such as remote mines, that also do not have access to power utility systems and so must generate their own electricity. In the majority of these cases, diesel gensets are the only source for on-site power generation.

“Using diesel gensets means that these locations have to rely on costly diesel fuel, transported long distances. While the price of fuel has dropped from the highs of 2014, the future of prices remains uncertain. And cost is just one consideration. Transporting fuel is a potential threat to the delicate environments that often surround these locations. Furthermore, greenhouse gas emissions and the effects of climate change—serious issues the world needs to address now—are directly related to the use of fossil fuels like diesel.

“A significant reduction in fuel usage for power generation can be achieved by integrating renewable power into a remote power grid, forming a hybrid power system, also called a renewable microgrid.

“Past attempts to incorporate renewable energy at meaningful penetration levels at these remote sites have proved challenging. Renewable power used to be expensive, and many early projects weren’t able to compete with diesel power on cost. The continuity of supply was an issue due to weather dependency and the variability of the renewable power generation itself. In addition, reliable and reasonably priced energy storage technologies and dynamic power management systems were not widely available.

“This is quickly starting to change. Hybrid power is on the cusp of making major leaps, thanks to falling costs of renewable energy, the maturity of several forms of energy storage technologies, and the advancement of smart, real-time dynamic control systems. We can now better integrate renewable energy into remote power grids through the improved performance and control of microgrids, with optimal sizing and use of energy storage. In many cases, over a power plant’s lifetime, the levelized cost of the electricity generated by hybrid power systems is becoming lower than the cost of the diesel-generated power.

“While the economic and environmental benefits are obvious, the social implications are even more remarkable. Besides local job creation for operation and maintenance of the microgrid facilities, these remote and island communities could free-up funding that was typically spent on energy consumption—mostly fossil fuel consumption—and invest in better infrastructure, schools, and recreational facilities.

“Hatch has developed a microgrid control system (HµGrid) that handles the energy management and power-flow control of renewable microgrids. Based on advanced optimization techniques, HµGrid uses intelligent, real-time software to monitor and manage the microgrid on a short- and long-term basis. This maximizes the use of the renewable power source, minimizes the consumption of diesel fuel, and enables the most efficient use of the energy storage system and power generation assets. It also helps improve the quality and reliability of the energy supply by compensating for variability in the renewable resource, reducing power outages and brown-outs.

“We have recently implemented a renewable microgrid incorporating HµGrid at a remote mine site near the Arctic Circle to much success. Renewable microgrid applications have the potential for a dramatic impact on remote mining, where fuel costs make up approximately 20% of operation costs or even more.”

The people behind that development have been nominated for induction into the International Mining Technology Hall of Fame.

“Hybrid power solutions enabled by smart, renewable and energy storage integration are gateways to an increased quality-of-life for remote and island communities and sustainable economic growth on a global scale.”