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Tracking down energy savings

Weyerhaeuser’s Princeton, B.C. sawmill is seeing some big-time cost savings from a number of energy initiatives the mill has introduced over the last several years—and the operation is continuing to track down energy saving opportunities.

By Paul MacDonald

At the Weyerhaeuser sawmill in Princeton, British Columbia, they have seen the light—quite literally.

Since the energy upgrades, Weyerhaeuser’s Princeton sawmill has saved 2.4 million kilowatt hours of electricity, and now has the highest energy efficiency of any of any of Weyerhaeuser’s facilities with dry kilns.

Over the last several years, the sawmill has done a major lighting re-lamp, which helped the operation reduce costs through the downturn, and continues to generate big-time cost savings.

The two-line sawmill processes enough logs to produce 294 million board feet of SPF lumber every year. A lot of logs means a lot of power is needed for lumber production and support facilities; 23 million kilowatt hours of electricity per year to be exact.

When the U.S. housing market—the main destination for a lot of Weyerhaeuser Princeton lumber—was in a slump, the sawmill was in lean times and needed to reduce fixed costs. With support from mill leadership, employees recognized that energy reduction would be an effective solution. And their natural gas and electricity utility, FortisBC, proved to be a helping partner in achieving that.

“With help from the FortisBC PowerSense program, we did a full lighting relamp in 2010,” says John McLeod, electrical supervisor, Weyerhaeuser Princeton. With the energy savings and rebates made available by the PowerSense program, the mill’s return on investment for the lighting upgrade took less than one year. “Plus the employees love the brighter LED lighting,” adds McLeod. “It makes it much easier for them to do their work.”

With the LED lighting, they have installed some 200 LED lamps. The wattages on the LEDs vary from 30 watt to 200 watt, and replaced High-intensity discharge (HID) and Sodium lamps up to 1000 watts in output.

“Since the lighting upgrade and with the support of FortisBC, we installed a refridge air dryer and have received lighting rebates on our LED upgrades ,” said McLeod.

John McLeod (far left), electrical supervisor, Weyerhaeuser Princeton, with Perry Feser, technical advisor and Certified Energy Manager with the FortisBC PowerSense program. Overall, the mill has been able to achieve energy savings of upwards of 12 per cent.

In addition, Weyerhaeuser Princeton has upgraded its capacitor banks to run tight power factors of from 95 – 97 PF, installed energy timers on production equipment and has built efficiency into equipment upgrades. They installed a Hankison HES 3000 scfm refridge air dryer to remove moisture from the compressed air system.

“The refridge air dryer was huge in itself in energy savings—that shaves 75 kVA off our system during the summer because we don’t need to run the less efficient desiccant system to dry the air.”

Older motors were replaced with new Toshiba high efficiency motors.

And the energy improvement efforts are continuing, notes McLeod.

“Weyerhaeuser has energy champions company-wide and our corporate energy team are actively engaged to find opportunities to further improve our energy efficiencies,” he explained. “And I really believe that engaging employees in energy efficiency and encouraging small changes to maximize savings brings home results. Changing one light to high efficiency may not make a big change, but change 100 and get 100 employees to turn them off when not needed, and you’ve made a big impact.”

That impact McLeod refers to can be verified. Since the upgrades, the mill has saved 2.4 million kilowatt hours of electricity. The Princeton mill now has the highest energy efficiency of any of any of Weyerhaeuser’s facilities with dry kilns.

McLeod started work at Weyerhaeuser Princeton in 2008, and since then he has headed up an energy effort, supported by mill management and employees, that has been thorough at tracking down, and implementing, energy efficiencies.

“We started out looking for opportunities, making changes that did not require spending a lot of money.”

FortisBC notes that energy use at the mill has gone down, by about a million kilowatt hours. But to meet the demands of the recovery in the lumber market, it’s important to note the mill is now producing 18 per cent more lumber. This means the mill is using a lot less energy to produce every thousand board feet of lumber.

McLeod explained that the re-lighting efforts started when an electrical products supplier said it would like to do a lighting survey of the mill.

The company essentially sponsored a program for retrofitting the lighting in parts of the mill. “We went from 400 watts to 330 watts on our high bay lighting, and that was a huge return on investment—the ROI on that was only eight months. FortisBC helped out with that project, too,” noted McLeod.

“At the time, we were already looking at energy saving opportunities throughout the mill, going after the low-hanging fruit in terms of making changes,” says McLeod.

The changes included taking a 350 hp main motor running on their hog system, and making it more of a helper drive. They had been running two 350 hp electric motors concurrently. “That shed 100 to 150 real hp off the system,” says McLeod. “Doing that was huge for us, energy-wise.”

The mill then went on to eliminate or downsize a number of 100 hp motors in the mill. “When we ran out of the 100 hp motors, we started going after the smaller motors. After we ran out of those, we went to energy timers, shutting things down when they weren’t running.”

In 2010, the mill installed an ION Metering system made by Schneider Electric, which monitors power and mill electrical usage, as well as kiln gas use.

In 2012, they initiated a pilot project concurrent with FortisBC Electric/Gas and installed an EEM, an Enterprise Energy Management system, which monitors variables. The software has been moved to Weyerhaeuser operations in Federal Way, Washington, to service the Weyerhaeuser network and is still in evaluation. This system models energy and provides a hierarchal approach to energy management.

“It does advance modeling and pulls data off our metering systems,” says McLeod. “Using production data, you can add variables and work up energy projects, and paybacks.”

McLeod explained that as part of a Weyerhaeuser company-wide effort to achieve energy efficiencies, each operation has an energy champion—and McLeod, being electrical supervisor, is the energy champion for the Princeton sawmill.

But he noted that it is very much a team effort, involving all mill employees. “It’s the people who turn the equipment on and off who make the difference,” he says. “They can tell us when a blower is running when it does not need to. We can put motion sensors on lights—but we get input on exactly where we should put them in the sawmill. You need to empower people in the organization.”

Sometimes, the changes are very straightforward; shutting down some conveyors and chains between shifts for example. “It’s one energy savings move, but if you make 20 moves, you achieve something substantial.”

While clearly the savings are in the details, it’s important to have a big picture approach, too, he says.

“Part of saving energy is that you need to understand the overall utilization of energy in an operation to find the best solutions because in a mill, work is still work—it takes x amount of work to produce a thousand board feet of lumber. And at the end of the day, it’s all about how you do that work,” says McLeod.

It takes so much work to process a log and produce lumber, and that does not change, he notes. How it changes is how you do it and what equipment you process that log with and how you support that with other assets.

In the case of Weyerhaeuser Princeton, the processing begins with cut off saws by Custom Design. The equipment on the large and small log lines includes two Nicholson A7 debarkers, and Kockums CanCar (now USNR) chip ‘n saw units. On both chip ’n’ saws they use Cougar XX round saws from Cut Technologies. The Cougar saws, which are manufactured at the Cut Tech plant in Penticton, B.C., are a good fit with Weyerhaeuser’s overall energy efficiency approach. They’re said to offer longer running times because the saws do not lose level and tension in operation.

MPM Engineering, of Surrey, B.C., has been involved with a number of projects at the Princeton mill, both in terms of equipment and optimization software. There are MPM Scanners on all log infeeds, primary breakdowns and trims. The mill edging equipment is Newnes, (also now USNR). The planer is a Stetson-Ross.

The mill has six Wellons double track 120’ dry kilns, from 13 MBTU to 20 MBTU, with single/double pass air flows.

As with all sawmills, the equipment and systems have evolved over the years.

Several years back, Weyerhaeuser Princeton contracted North Vancouver-based LNS Services to design, supply and install a new log processing system for short logs. This new system allows the mill to process a wider variety of logs and meet the demands of a changing marketplace. LNS worked closely with Weyerhaeuser to design an efficient system that integrated with its existing infrastructure.

Back in 2008, Lucidyne did five GradeScan installations for Weyerhaeuser with systems in British Columbia, Alberta, and North Carolina. The B.C. application required Lucidyne to integrate information from a Metrigard CLT machine and a Northern Milltech moisture sensor to grade machine stress rated (MSR) and dimension lumber. The mill requires the scanner to process lumber at speeds up to 2,250 ft/minute. Weyerhaeuser Princeton inherited this scanner system from another company operation in B.C.

There have also been some changes out in the millyard; they recently installed a trailer reload from Mussell Crane Manufacturing, of Chilliwack, B.C.

Current projects at the mill include the installation of three Comact wave feeders at the front end, two -24 foot and one 60-foot, to help better process the smaller wood the operation handles. Installing the wave feeders will allow the operation to switch out some heavy duty hydraulic equipment, for variable frequency drives. They’ve also made a significant shift to variable frequency drives on the sawmill lines, as well, installing a number of Mitsubishi VFDs from Arrow Speed Controls.

All of the above changes, while efficient, still require energy.

Sometimes, McLeod explains, their energy conservation efforts involve finding substitutions for hydraulics and air. “We might want to use electrics rather than hydraulics because of the efficiencies it delivers when you are doing work on demand.”

Over the last half-dozen years, they’ve kept track of all the changes. Big and small, there have been about 120 projects, or tasks, as they’re called at the mill. Some are big like the lighting changes and variable frequency drives. “Some just involved work orders,” says McLeod. “But they all count.”

That effort towards saving energy is still there, says McLeod. “The first four years were huge for us, and we’ve tapered down, but the philosophy and mindset is still there. It’s important to go after the low hanging fruit in energy savings, but you still go after the branches, too, after the low hanging fruit.

“You make some major moves, but you don’t stop,” he added. “Each opportunity saves a bit of money, and it all adds up.”

And with energy prices, both natural gas and electric, being unpredictable, it helps them get a handle on a very large fixed cost for all sawmills.

Overall, the mill has been able to achieve energy savings of upwards of 12 per cent, which McLeod said is realistic on a practical basis. “Based on our studies and equipment queries, there are projects that will realize larger returns—but then these systems typically have large capital investments with longer paybacks.”

McLeod said that it’s important to implement energy saving initiatives, but it’s just as important to stay on top of them. “With any program, if you don’t own it and maintain it, it’s going to fall by the wayside as other priorities inevitably come up. We need to stay focused on it—and it can be as simple as something like monitoring your air usage in the mill.”

Going forward, it’s clear there is going to continue to be a focus on energy savings at Weyerhaeuser Princeton.

Funding available for energy projects in B.C. sawmills

B.C. sawmills that work with utility company FortisBC to optimize their energy use can qualify for funding towards energy studies and significant rebates once an eligible project is complete—from $1,000 for small energy efficient lighting projects up to $1 million for large-scale equipment upgrades. Plus, energy efficient sawmills can cost less to operate and provide a more comfortable environment for staff, FortisBC notes.

The process most often starts with an energy study to identify where investing in energy saving upgrades will yield the best return. The study also provides a baseline for calculating potential savings and rebates. Once a project is complete, the rebates are granted based on verified savings. These rebates can reduce the payback period for some participants to as little as one year.

“Contacting FortisBC right from the planning phase of your project is key to qualifying for programs and incentives,” said Perry Feser, technical advisor and Certified Energy Manager with the FortisBC PowerSense program.

Feser helps sawmills like Weyerhaeuser Princeton throughout their entire upgrade or building process, from accessing energy study funding to verifying savings. “Sawmills can find significant electricity savings by installing more energy-efficient systems, equipment and technologies, redesigning processes or implementing controls on existing energy-using devices,” said Feser. “For natural gas savings, sawmills can look to their wood drying processes and whole building space heating systems.

“Sawmills aiming to meet carbon reduction or other environmental stewardship goals can also choose renewable natural gas, which is captured from organic sources in B.C.,” added Feser.

Sawmills considering new and retrofit projects can contact a FortisBC PowerSense technical advisor to apply for audits, energy studies and incentive programs.