Motor Skills

In an exhaustive energy-monitoring program designed to save money in utility costs in both the short and long term, Canada’s Dufferin Concrete signed

Steven Prokopy

In an exhaustive energy-monitoring program designed to save money in utility costs in both the short and long term, Canada’s Dufferin Concrete signed a multiplant contract with Inventure Systems to track power surges and peak consumption, and determine whether the ready mixed producer’s equipment requires further modifications.

Dufferin is a subsidiary of St. Lawrence Cement, whose Swiss parent company, Holcim Group, has been at the forefront of environmental and conservation measures. Its initiatives include sponsorship of the Holcim Awards for Sustainable Construction; inaugural membership in EPA’s Climate Leaders program; and, heavy promotion of green building, use of more efficient means of transportation, sourcing alternative fuels, as well as use of recycled materials, such as slag and fly ash, in concrete production.

Dufferin is a leading producer of ready mixed to the southern Ontario market, with 32 plants within the region’s three districts and more than 700 employees and 1,700 customers. Inventure supplied equipment to Dufferin for its four most recent startups, and as part of the contract Inventure came in to monitor Dufferin’s Markham facility, a central mixed plant opened in September 2008 with underground aggregate storage and dual aggregate scales.

Whether enlisted to do a complete tear-down-and-rebuild or a modernization of an existing facility, Inventure was able to walk through each plant design with Dufferin staff, using individualized 3-D plant layouts or solid modeling. This allowed for a high degree of customizing and cost savings, as well as minimizing complications during installation.

As can be seen from the plant diagram on page 28, the Markham operation includes motors for two belts under twin agg scales (these are live bottom, so variable frequency drives are used to control aggregate charging speed); an incline belt elevator; a cement screw; four for the mixer, all coupled to one drive; a dust collector fan; a compressor; pumps (grey water and washout); and, an operations building.

By monitoring all the motors, the plant can isolate which devices are causing surges and deal with those so that the majority of the payback is from an energy-saving perspective. At this particular facility, 60 percent of the energy bill was found to be accrued at maximum peak demand, due to the incline belt. From an audit of the operation, Inventure came up with an energy-savings proposal where a $20,000 investment would pay back in two years. In addition, there were further savings in the total usage of power identified. Inventure believes that anticipated savings of $10,000-$30,000/year are not unrealistic for this type of overhaul.
Û Inventure Systems, King City, Ontario; [email protected]


A 16-page white paper entitled The Economics of Improving Power Factor, authored by Ed Kwiatkowski, E.E., president of Dayton, Ohio-based Staco Energy Products Co., is now available. The paper includes formulas, charts and graphs to help the reader understand power factor; how utilities charge for inefficient use of power; and, the economic relevance of improving it.

Examples are provided along with formulas so that readers can substitute data from their own situations. The paper also discusses how companies that are operating at the upper limit of their transformer’s capacity may be able to forego the purchase of a new transformer by more efficient utilization of their existing power.

The paper is a response to many questions that we’ve received from customers about the payback for power factor correction equipment, says Kwiatkowski. Although each utility charges for their power differently, virtually all impose penalties for poor power factor Û some less obvious than others. This paper shows that companies that improve the efficiency of their power usage can avoid those power factor penalties. There may also be reductions in utility bills, but the payback comes from the elimination of penalties.

Copies of the white paper are available online at


In late 2007, President Bush signed the Energy Independence and Security Act (EISA). Effective December 2010, it mandates motor efficiencies beyond the minimums of the 1992 Energy Policy Act. Tip for motor buyers: Evaluate if exceeding EISA’s efficiency minimum will provide a competitive advantage for motor-driven products.

EISA will keep motor makers busy advising and assisting customers over the next few years. For example Baldor Electric Co.’s current annual report states, We will be working closely with our customers to make sure they are using the appropriate premium efficient motors as required in the new energy bill.

Randy Breaux, Baldor’s vice president of marketing, says many OEMs will be required to upgrade from a standard efficient motor on machinery they produce to a premium efficient model. His advice to motor buyers: First determine if even more efficiency could be competitively advantageous for the motor applications. The company’s highest efficiency models, the Baldor/Reliance Super-E motors, exceed EISA requirements. Breaux says the Super-E motors, now being prototyped, offer performance efficiency that OEMs could apply to competitive advantage.

Any upgrade process should begin with an understanding of initial cost versus lifecycle cost, says John McFarland, Baldor’s chairman and CEO. Consider that the lifecycle cost of a typical AC induction motor consists of only 2 percent for the purchase price and over 97 percent for the energy used over its life, adds John Malinowski, the company’s product manager, AC & DC Motors.

Breaux explains that while the upgrade to premium efficient motors required by EISA will raise initial motor cost 10 percent to 15 percent, the added efficiency will recover the extra cost in six to 12 months. Adds McFarland, The savings in electricity will then continue year after year. And since motors often last 15 to 20 years, the lifecycle savings can be substantial, if the right decision is made up front.

Even greater efficiency gains can be achieved by using adjustable-speed drives in certain applications, particularly pumps and fan applications, McFarland notes. In some cases an adjustable-speed drive can reduce power consumption by half. He says running an adjustable-speed drive could also enable other efficiencies in the process. He estimates only 5 percent to 10 percent of all industrial motors are equipped with adjustable-speed drives, and according to the Department of Energy (DOE), as many as 25 percent could be or should be.

With motors accounting for 60 percent of industry’s electric power bill, McFarland sees motor efficiency as an issue of growing global consequences. He recalls a Department of Energy study from the beginning of the decade concluding that high-efficiency motors, appropriately used, could reduce industrial power consumption by as much as 18 percent. He says gains in motor efficiency imply billions of dollars of savings that could be used to improve industry’s profitability or competitiveness in world markets.