Four Seasons keeps cool in face
of rising energy costs
and surround the top and sides of a trailer,
and seals, which work by pressing up against
the truck, are designed to prevent air from
escaping. If your operation doesn’t already
have these devices in place, investing in them
would be a good place to start.
But it’s not enough to simply install these
devices; you have to keep them in good working order. Seals and shelters can lose effectiveness over time—whether through normal
wear and tear or damage. That’s why it’s a
good idea to regularly inspect seals and shelters and replace old and damaged units.
It’s worth noting that the cause of sealing
failures isn’t always obvious. Sometimes, the
fault lies not with the seal, but with the door
itself. As Sprunger explains, it’s not unusual
for a door to get hit and end up with a kink in
it. Although the DC often is able to get the
door working again, there may be residual
damage—like panels that have been knocked
out of alignment, creating a gap of a quarter
inch or more and compromising the seal. To
avoid this, Sprunger recommends installing
dock doors that are specifically designed to
withstand abuse, like those with impactable
bottom panels.
Utility rate increases may be a fact of business life, but the hikes Ephrata,
Pa.-based Four Seasons Produce was looking at four years ago were in a
category of their own. With Pennsylvania’s electricity price cap set to expire
on Jan. 1, 2010, the produce wholesaler had been running some numbers
to see what kind of hit it would take. The findings came as something of
a shock: Four Seasons learned its utility bills would rise anywhere from 20
to 40 percent. That was all it took for the company to launch a wholesale
energy conservation effort aimed at generating savings roughly equivalent
to the increase—somewhere between 20 and 30 percent.
One of the first areas to come under scrutiny was the company’s
bustling distribution center, a three-shift operation that runs six and a
half days a week and handles more than a million cases a month. “We
started by looking at areas of the facility where we knew we could
reduce our energy use,” says Randy Groff, Four Seasons’ director of facil-
ities and energy. “The building envelope, including the dock area, was
one place that we knew we could generate some savings.”
That assumption proved correct. A review of the operation revealed
significant energy leakage at the dock’s 35 doors—a serious concern
for a refrigerated operation that requires its docks to be kept at a cool
40 degrees F. Part of the problem was that the original dock shelters
were designed for tractor-trailer barn-style doors. When the company
had to load or unload anything smaller, the result was a significant
gap between the shelter and the vehicle.
To plug the leaks, the company invested in dock shelters and seals.
In 2009, Four Seasons installed Rite-Hite’s Eliminator-GapMaster dock
shelters at all of its loading dock doors to seal the gap at the trailer
door hinge. It also put in Rite-Hite’s Pit Master under-leveler seals,
which eliminate the gap between the leveler and the pit wall.
“It’s now a lot easier to keep the ice on the broccoli,” says Nelson
Longenecker, Four Seasons’ VP of business innovation.
How did the company do against its target? Quite well, it turns out.
Its overall conservation initiative, which also included a lighting retrofit
and the installation of a DC energy management system, produced savings of almost exactly 25 percent. “We hit our goal of having a smaller
electrical bill this year than we did four years ago,” says Longenecker.
Draft dodging
Although seals and shelters can go a long way
toward stemming energy loss, they’re not
always enough. Even with these devices in
place, dock doors can still be drafty. If that’s
true of your operation, there are a couple of
other possibilities to investigate.
One is the so-called “hinge gap.” Most over-the-road trailers have doors that hinge open as opposed to
rolling up. When the truck backs into the dock, the dock
shelter then seals to the inside face of the trailer door, as
opposed to the trailer’s outside wall. The result is a vertical
gap between the outside wall of the door and the outside
wall of the trailer, where air can rush in and out, says Walt
Swietlik of dock equipment maker Rite-Hite.
Specialized seals designed to close off the trailer hinge gap
during loading and unloading can help plug this type of
leak. Rite-Hite also offers a dock shelter that has hooks that
extend over the hinge, sealing it off from top to bottom.
Another place to check for leaks is the dock leveler, the
device that bridges the gap between the truck or trailer door
and the loading dock. Oftentimes, gapping occurs at the
corners on either side of the dock leveler. As Swietlik puts it,
as you look down on the leveler, there are two squares of
white space on either side of it.
