Electricity surges across the Northwest (Ontario) Power Grid’s 44-kV, three-phase, 60-Hz power lines before feeding 11 megawatts of energy to the transformers south of the mill building and main switch room of Placer Dome Inc.’s Campbell mine. They step it down to 4,160, 2,300 and 575 volts, and the resulting power drives the operations that pull gold from shafts carved into the Canadian Shield.
Physics meets geology
It’s an inescapable reality that you need to consume energy to mine any precious metal, mineral or gem. Loads of it. And Placer Dome gives a piece of its bottom line in return. Electricity alone now accounts for around 8% of the operating budgets at its Ontario mines.
Yet while utility costs can have a direct impact on an operation’s profitability, it can be difficult to pinpoint wasteful activities, or to schedule processes to take advantage of the cheapest-possible energy rates.
“Prior to Envision, what we’re doing typically is some high-level meter reading, but we haven’t necessarily been at the process level, where you’d like to be,” says Chuck Hennessey, Placer Dome’s director of asset management and loss control, referring to his company’s continuing efforts to control utility expenses. Reports can be developed based on functional activities such as crushing and grinding, for example, “but you don’t get that granularity you need to make true business decisions.”
That analysis is now being refined thanks to a software package known as Envision, which is beginning to offer an improved picture of energy use within Placer Dome’s Ontario mines, measuring the power draw of each process.
A certain irony shouldn’t be overlooked: the software designed with the purpose of tracking, and ultimately reducing, power consumption has been developed by Ontario Power Generation–the same entity that generates electricity in the first place.
“The biggest factor is for people to realize that [reduced] energy usage is a competitive advantage,” says Peter Sprukulis, Ontario Power Generation’s vice-president, marketing. “If you measure it, it gets managed, and if you manage it, it will make money.”
The power company is targeting businesses that spend at least $2 million per year on combined utility bills, in the hopes of selling them the software that shows exactly where energy of every sort is consumed. Mines offer an obvious market because of their thirst for utilities, and Placer Dome is counted among the first handful of customers.
“Campbell has been able to use Envision to control costs during extreme peaks [in electricity consumption], and look at how some of their loads react,” Hennessey explains.
So far, the software has helped Placer Dome shed a mere 1% of the electricity costs at the location, and these savings have come by helping to determine when some process activities could be delayed. But the additional savings are expected to come when the software is used to track an array of utilities, including everything from natural gas to propane and compressed air.
Based on the early signs of success, Placer Dome has decided to connect Porcupine Joint Venture and Musselwhite mine (both of them shared with Kinross Gold Corp.) to the software by the first quarter of 2004. The resulting networked information will then offer a real-time snapshot of energy consumption throughout all three northern Ontario locations. (Ontario Power Generation was configuring the required hardware as this article was being written.) With that information, Placer Dome hopes to make the business decisions that will require less power.
Pump applications will be the first to be analyzed, along with lighting systems, Hennessey says of the energy draws. “Ventilation fans are another big one.”
Such activities as secondary pumping will be delayed to hours when electricity rates aren’t peaking; ventilation fans will be shut down when work areas are empty. “And this goes beyond [traditional] utilities and gets into things like compressed air,” he adds, referring to productivity improvements that can come by measuring each shift’s use of the commodity.
In fact, the only requirement for measuring any commodity is a meter that communicates over a common standard such as a modular operating device, says Paul Christilaw, Envision’s manager of technical sales.
Coupled with the real-time monitoring of utility costs, energy managers can also use this information to switch between different power supplies. One Envision customer uses the software to determine whether a pair of on-site locomotives should generate electricity, plotting their maintenance and diesel costs against the cost of electricity from the power grid.
The Envision software will generate e-mail messages or pager alerts when utility costs pass pre-set thresholds, Hennessey says. “It’s also easy to hook into a PLC [programmable logic controller] and, once it gets above a specific threshold, run an algorithm and automatically shut down loads.” Granted, Placer Dome is currently limiting the software to a reporting function until it proves itself, but the capability exists.
Envision software can also monitor whether a higher energy draw warrants equipment repairs or replacements. “Compressed air systems are notoriously leaky,” explains Christilaw. Alarms can sound once they begin to draw more than a pre-determined amount of electricity.
These same alerts can even be used to help manage energy purchases.
“When you buy a contract in Ontario, it can be an aggregate,” explains Envision manager Eric McCarthy. “In order to know whether I’m inside or outside that contract, I need to see an aggregation of all of the loads for all those sites on a real-time basis.” Otherwise, you’re left to pay higher costs for the additional energy. “But when you buy that hedge contract, it’s difficult for you to see how much of it you’ve used at any given time.”
Software-generated reports can also be used to check the accuracy of utility bills, which can be a time-sensitive task for companies that need to pay their bills within a few days of receiving an invoice.
“The reports are pretty good. It’s not the easiest thing to configure, but you can get the information you need,” Hennessey says of the software. “One of the reasons we went with [Ontario Power Generation] is we believe they’re going to develop the product.”
Envision costs begin at $125,000 and push upward depending on the related hardware and software that needs to be added. However, even those who developed the software admit that it isn’t a proverbial ‘silver bullet’ to slash energy costs in half.
“Envision is generally not the kind of technology where you save you save half a million dollars twice a year,” says OPG’s Christilaw. “But if you save $50, $100, $200, and you save it across multiple (processes), across multiple facilities, across several hours a day, times 365 days a year, all of a sudden those savings have a tendency to grow very quickly.”
John G. Smith is a freelance writer based in Ajax, Ont., who specializes in industrial and transportation issues. He can be contacted at [email protected].