Run on demand
When the subject of green equipment comes up, conveyors probably aren’t the first thing that comes to
mind. But actually, today’s conveyors are engineered
to save electricity. A prime example is the motor-
driven roller (MDR) conveyor, which is
designed to power down when not in
use—a significant departure from
traditional conveyors, which run
continuously during operating
hours. Although they’re more expensive than conventional models, MDR
units typically pay for themselves many times
over in energy savings and reduced maintenance
expenses (because the units don’t run continuously,
there’s less wear and tear on components). The “run on
demand” feature alone reportedly cuts power consumption by at least one-third.
Even if you have an old conveyor, you may
still be able to save money by converting it
to a more energy-efficient design. A number
of conveyor companies offer retrofits for
existing systems that involve replacing old
drive motors with more efficient units.
Many of today’s conveyor systems feature a
modular design that allows them to be easily
repositioned or even moved to another facility as
distribution needs change. That versatility can help
extend the conveyors’ lives far beyond the time when
units are ordinarily consigned to the scrap heap.
Manifest destiny
When it comes to opportunities for going green, it’s hard to
imagine an area of DC operations that offers more potential than packaging and shipping. For starters, there are the
shipping containers. Rather than relying on corrugated
boxes, consider the reusable plastic container for closed-loop applications. Advocates say the plastic units are cheaper to use in the long run and provide better protection than
corrugated. And the containers are designed to nest when
empty, making them economical to store and transport.
If plastic containers aren’t an option, there are still steps
you can take to make your operation more sustainable. For
example, you can select cartons made of recycled materials.
You can also review your operations to make sure you’re
choosing the right size carton for each shipment. Cubing
systems make it easy to determine the volume of each order
as well as the optimal carton size. Smaller cartons use less
material, save on transportation costs, and require less void
fill to protect their contents.
As for void fill, again, look for products that can be recycled. Kraft paper made from recycled material is an eco-friendly choice. Air-filled cushioning is another good
option—one that requires minimal storage space and is
also readily recyclable. There are also peanut-type cushioning products on the market today that are made of cornstarch and other water-soluble materials, making them a
biodegradable alternative to foam-based packing peanuts.
Although often overlooked, green opportunities can also
be found in a facility’s printing and labeling operations. For
example, you might be able to switch to a smaller shipping
label, or replace your current labeling system with one that
prints the shipping information on one side of the label and
the packing slip on the other (thus saving paper). You might
also consider dispensing with shipping labels altogether in
favor of an inkjet encoding system that prints shipping
information directly onto a carton. (If you do, look for a
system that uses environmentally friendly inks.)
Of all the equipment in a distribution center, the item
most likely to be recycled is actually the wood pallet. Most
facilities repair and reuse pallets until they’re no longer
serviceable, and nearly all pallets are eventually recycled.
While some argue that wood pallets are the greenest choice
because they’re made from a renewable resource, others consider plastic and metal pallets to be more eco-friendly because
they can be reused hundreds of times (see “how green are
your pallets?” DC VELOCITY, November 2008, www.dcveloci-
ty.com). Still others advocate for pallets made from fiberboard, corrugated, and other materials that are easy to recycle.
In it for the long haul
Like conveyors, lift trucks, which are the workhorses of most
DCs, have become greener in recent years. That’s partly
because manufacturers have shifted some of their emphasis
from internal-combustion engine models to battery-operated trucks that produce virtually no greenhouse gas emissions. In the meantime, research continues on alternative
fuels, like hydrogen fuel cells, that show great promise.
Even among electric models, many of today’s trucks are
greener than their predecessors. There’s been a shift away
from units that rely on direct current (DC) electricity in
favor of alternating current-powered models that use less
energy. And lately, manufacturers have introduced hybrid
electric models that generate power from energy used in
vehicle braking and mast lifting operations.
At the same time, advances in electric battery design and
charging technologies have increased the power output of
standard cells, making electric trucks more eco-friendly
