The full backup power generator installation at a Wisconsin lumber processing company is a key element in its utilization of lean-manufacturing processes.

By Don Talend

A prime example of the impact of competitive forces on manufacturing of all kinds—and technological and management solutions that address that impact—can be found at Wolf River Lumber in New London, WI. One might be inclined to think that this company, which provides premium materials for North American cabinetmakers from its production facility in a semirural region of northeast Wisconsin, as some kind of Old World artisan outfit. The reality is as far from that inclination as possible; Wolf River Lumber operates a state-of-the-art facility and has embraced lean-manufacturing techniques. The company has also taken major steps to guarantee customers its own continuity of operation, and its own backup power supply is the key element of this strategy.

Photo: Generac Power Systems

Wolf River Lumber in New London, WI is a highly automated, lean-manufacturing operation that management recently decided to safeguard with a total backup generation system.

In early 2007, the company installed a comprehensive 3-MW backup power system consisting of four 750-kW Generac Gemini Twin Pack gensets, each of which has a pair of 375-kW diesel generators mounted side-by-side in a single enclosure. The gensets also use onboard paralleling technology to combine their output. Mark Christopher, Wolf River Lumber general manager, explains why installing the system was so important to the company’s strategy. “With our industry and our business, it’s essential that we’re up and running,” he says. “We’re pretty much a next-day supplier—we’re kind of a supermarket for the hardwood industry, specifically the cabinet people. With lean process becoming more prevalent in manufacturing today, people want next-day delivery. Well, in hardwood lumber, you have to have a large volume of inventory and then the specs with the cabinet manufacturers may change the next week, the next day.”

Company is a One-Stop Shop
The company’s 335,000-square-foot main building, which houses the corporate offices, production facility, and a large warehouse, was built in 2001. On the exterior of the building are 40 steam-heated kilns in which raw lumber is inventoried and dried. The kilns are heated by three 600-horsepower, natural-gas-fired boilers that are backed up with liquid propane; one of the boilers can run on biomass material or coal.

Every day, Wolf River Lumber receives deliveries of varieties of lumber such as oak, maple, birch, walnut, butternut, cherry, and ash from area mills. The lumber arrives in random lengths and is put on a conveyor. Certified lumber grading specialists sample the lumber and mark the grade. Following the inspection and grading process, the lumber goes through a scanner that records the dimensions of each board and tallies the total number of board feet of each grade. Then, the boards are sorted and stacked by grade in the kilns.

The aluminum/stainless-steel kilns are equipped with large sliding doors for forklift access, steam pipes that dispense heat ranging from 90°F –160°F, and fans for evenly distributing the heat throughout the lumber. The large number of kilns is necessary, given the number of wood varieties and their varying temperature and drying time requirements.

“We have 2 million feet of kiln capacity in our 40 dry kilns, with each one holding a little more than 55,000 board feet,” notes Christopher. “All of our power comes from our boilers; we use steam to heat the coils and we actually add live steam into the process to relieve the stress in the lumber.”

The production facility has four service areas in which wood processing and finishing take place. After the lumber is dried in the kilns, it is moved into production. First, each board receives a smooth or rough finish from one of two planers. Precise dimensioning of each board occurs next, as computerized saws cut each board to a standard or custom length. This precise dimensioning is another reason why Wolf River Lumber can position itself as a one-stop shop to customers who do not have to do their own dimensioning.

Photo: Generac Power Systems

The company has positioned itself as a “hardwood supermarket” and has invested significant capital in kilns to dry out lumber, and in machines for sorting and dimensioning the product.

The facility’s intricate mass-customization capabilities and strategic positioning as a just-in-time supplier places even more importance on keeping processes running than in a typical manufacturing operation. “If we ever went down in the dead of winter, when it was, say, 20 [degrees F] below [zero], 30 below, and if our pipes ever froze, it would take us forever and a day to rebuild,” says Christopher. However, he indicates pulling off lean manufacturing with a foolproof backup power supply might cause customers to depend on Wolf River Lumber for most or all of their finished wood supply. With construction of the new facility, the company already had the facility and the process; all it needed was reliable power backup.

Full Power Backup Chosen
At first, Christopher points out that the company considered partial power backup compared with its total consumption. “All of us put our heads together—[company owner and president] Gary [Ort], myself, our maintenance manager Michael Harder and Cal Lehman of Master Electrical Services, the electrical contractor, to figure out the best strategy,” Christopher reports. “We looked at fully backing up our dry kilns, which would be putting two of these units in and then maybe giving ourselves enough power to keep some heat on in our building. We figured that, given our facility’s 335,000 square feet filled with 12–14 million feet of lumber, it was going to take a long time for that to cool down and everything where it would be detrimental to our sprinkler system.”

Consulting with the local utility, New London Utilities, convinced the team that full power backup would make economic sense. “We finally brought in our power supply people,” says Christopher. “We’ve got a local utility here in town: New London Utilities, which is part of Wisconsin Public Power, and we started getting them involved in the process. We found that they would be willing to work with us to have this backup power generation. As we learned more and more about that, we decided that if we’re going to do this, why not have full backup for the full operation? We figured that, as we grow, we could go [to our insurance company and we would] get a full guarantee for customers and our employees that we would be up and functional no matter what would happen.”

After considering several options, Ort and Lehman of New London–based Master Electrical Services decided that the Generac Gemini system best suited the full backup configuration. The system meets two of Wolf River Lumber’s specific needs—redundancy and scalability/expandability. The parallel design of each genset meets the need for redundancy. The fact that the system is part of the manufacturer’s Modular Power System means that it is scalable. Customers can have the necessary capacity installed for an existing system and add up to six more Gemini units in the future. According to Lehman, the 277/480-V, three-phase installation consists of four separate areas of power supply, with the automatic backup system having 1.5 MW and the manual backup system having another 1.5 MW. The flexibility of the backup system allows the entire facility to be removed from the grid, if necessary.

After the backup infrastructure decision was made, Lehman and the team worked out the details of installation, taking into account factors such as production requirements, traffic patterns, future expansion plans, and utility requirements when deciding on the location of the generators and transfer switches. Two of the gensets combine to back up the main building and the other two are located separately near the kilns.

Ryan Dutkiewicz, a master certified field technician with Brookfield, WI–based Wolter Power Systems, the local dealer for Generac, reports that the process of getting the backup system online went very smoothly. “It was the first Gemini that they hooked up and our engineering department provided them with accurate drawings. They were ready for me 100% at startup.” On the day when the backup system went online, Wolf River Lumber’s maintenance department planned to have transfer tests take place during the lunch hour. Following the startup, the generators powering the main processing line were kept on to prevent downtime that would result from switching back to utility power.

“The comical thing was that as we were getting ready to connect the first generator, we had the first-ever power outage in the history of Wolf River Lumber,” Christopher recalls. “I just stood there and threw up my hands at all of the employees. This happened at about 11 o’clock, and I said, ‘See? If we had all of these generators in, we’d all still be working.’ We wound up sending about 100 or 150 people home. We could actually see how essential it is to our business to keep power going.”

Christopher explains the wisdom of the automatic start system for the kilns and the manual start system for production. “If we have a power surge or outage at our kilns and our boiler room, then it gets backed up with an automatic start system,” he says. “It’ll be a matter of a few seconds’ delay, and then the generators will automatically start up and bring themselves up to power.” Conversely, “We didn’t configure the other two generators that run our plant that way because we didn’t find an outage or surge to be as detrimental; we would be down 15 to 20 minutes and we’d go down and start them up and switch a few breakers over. That was our decision because automatic startup is expensive.”

Christopher adds that the system is self-monitoring, so that if backup power is needed during a time like the present, given the slowdown in the housing industry, the system will run at less than 100% output. In some situations, not all of the generators would need to be in use. Christopher notes that expandability was an important consideration in deciding on the ultimate configuration, too. “It would be pretty easy to expand; we do have excess capacity on the generators that supply power to the building and that gives us the capacity to build on,” he says. “Right now, our kiln capacity is probably favorable to us for the next five to 10 years. We look at our major growth as being in our manufacturing plant.”

Photo: Generac Power Systems

A large number of kilns and storage is necessary, given the wide variety of hardwoods processed.

With a successful installation complete, Christopher reports that Wolf River Lumber can now position itself as a lean-manufacturing company that can respond to customer needs without fail. “I think the confidence of the personnel here is worth a fortune in itself, knowing that we have this backup,” he says. “My biggest fear as general manager of the plant—of course nothing ever seems to happen when it’s sunny and 80 degrees—but when it’s 25 below, I’m sitting there worrying about whether we’ve got heavy snow and heavy wind with all of our power lines and the millions of dollars of equipment and millions of dollars of product sitting there. It definitely allows me to sleep easier at night knowing that if anything does happen, it’s automatically done with our kilns and it’s a matter of 15 minutes to get the plant up and going.”

The benefits of full backup do not end at management’s peace of mind, however. The backup system also positively affects customer relations, Christopher adds. “With lean manufacturing, Wolf River Lumber is going through a journey of learning right now. The main concern that we’ve had is keeping our customer and keeping our customer satisfied. They have that security of knowing that we’re going to be here. When I’m touring people through our plant, that’s one of the main things: guaranteeing to them that under any circumstances, we’re going be able to support them in their lean ventures. We are not going to go down. It’s like any manufacturer—a one-day delay in sending a product may lose the order. That’s our goal; we’re guaranteeing them that we’re going to be there for them tomorrow and the orders will be there for them on time.”

The result of the plant upgrade is that the company is getting more business from existing customers, which leads to a more profitable business. “Typically, in our situation with some of the large cabinet manufacturers, we would normally only supply them maybe 10%–30% of their product in a lot of cases,” Christopher continues. “Well, with what Wolf River Lumber has done, not only with the generators and backup, but in some of our processes, they come in and see that we even have a sister plant so that even if anything catastrophic were to happen to Wolf River, we would be able to take our people to our sister plant and operate there. All of these things have allowed us to get anywhere from 10%–40% more business from the same people.”  

Don Talend is a communications and publicity consultant specializing in the trade media.

DE - March/April 2008