Whether in the form of light, heat, or raw motive power, energy's invisible ubiquity makes it tough to manage. Ignore it, however, and such costs will eventually catch the attention of any company's CFO.
This article focuses on several strategies to get a handle on energy costs.
One caveat: No energy-saving strategy
will be effective unless
it becomes part of the company's culture. We'll shed more light on that
later. First, let's look at managing lighting's cost.
1. Install New Light Fixtures
American Security (Fontana, Calif.,
www.amsecusa.com), manufactures
steel safes, from raw sheet metal to
bending, plasma cutting, welding,
painting and assembly. It makes most
of its parts in-house, so between making parts and making safes, material is
in constant motion. As these processes
change, so must the space surrounding
them. To gain flexibility in the plant,
the manufacturer converted its warehouse from a standard open floor
space with a mezzanine to one serviced
by highbay racking that increased storage capacity.
American Security is just beginning
to implement cellular production
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and
other lean manufacturing processes.
That's what makes production floor
flexibility so important. As these
processes change, so must the lighting.
That can be expensive. Task lighting
has to be moved every time a work cell
is moved. That's why John Soler, American Security's production manager,
decided to eliminate metal halide task
lighting altogether.
In its place the operation relies on a
constant light level throughout the
plant produced by new high output,
four-lamp T5 light fixtures. This lighting results in better light quality, distribution and efficiency. The new fixtures
pump out more light and save energy
costs to the tune of $2,500 a month.
Lighting is a small fraction of American Security's electric bill. It consumes a lot of power thanks to 100
welders who use plasma equipment.
This put the manufacturer in a position to work out a sizable rebate from
the power company. American Security used this rebate as a deposit on the
lighting project.
Part of the energy savings comes
from the use of motion sensors wired
into the ballasts of the T5 fixtures. If
the sensors detect a lack of motion for
an extended period, two of the four
lights turn off.
"I feel strongly that lighting is important to people's attitudes and emotions," says John Soler. "Second, you
can't see defects if it's too dark. We
were having quality issues, especially
with the paint quality of some of our
high gloss paint finishes. It wasn't just
the lighting in the plant but the lighting in the paint booth. Energy efficiency was the final selling point that allowed us to make all these changes to
the plant and have a positive impact
on production while saving us energy.
The return on investment came within
36 months."
2. Take Advantage of Government
Incentives
The cost of lighting is driven by two
things: the rate, which users cannot affect, and the wattage, which they can.
According to Gloria Davis, a lighting
consultant and utility specialist associated with American Lighting Supply
(San Diego, www.americanlightingsupply.com), the new fixtures that American Security installed can reduce wattage by at least half. She says that users
can also cut maintenance by half because these fixtures last longer.
"With the Energy Policy Act passed
in 2005, a business can write off a project like this the year it's done, rather
than spreading it out over 5-7 years,"
she says. "That catapults the payback
period. This is in addition to the rebate
and in addition to the savings users see
on their energy bill."
The Energy Policy Act of 2005
(www.energy.gov/taxbreaks.htm) offers consumers and businesses federal
tax credits for purchasing fuel-efficient
hybrid-electric vehicles and energy-efficient appliances and products. Most of
these tax credits will remain in effect
through 2007.
To qualify for this Federal tax incentive for lighting, users must install
bi-level lighting, with occupancy sensors. The lighting must also be below a
particular wattage per square foot and
per fixture, which Davis says is easy to
get to with newer more energy efficient lighting.
"Even with the additional light we
gave American Security's facility,
they're saving approximately $30,000 a
year on their Edison Light bill," Davis
adds. "The cost of the project was
$144,000, and that was for tripling his
light. If this had been a one for one fixture replacement, John's payback
would have been much quicker—less
than a year."
3. Use HVAC More Efficiently
Brigade Quartermasters Ltd.
(www.actiongear.com) is a military
gear and clothing catalog house based
in Kennesaw, Ga. Summertime here
brings 90- and 100-degree temperatures. This cataloger's 37,000 sq.-ft.
warehouse went 20 years without air
conditioning. It wasn't until the company decided it needed denser, higher storage that management realized a change was in the air.
"Mezzanine picking was not feasible
without dealing with the environment
of the building," says Geoffrey WerBell,
the company's CFO. "When we started
the project we had 8,000 pickable SKU
sites. After re-racking we had 19,000, so
we got higher efficiency out of the
building. But we knew we couldn't put
someone eight feet up in the air in a
130 degree temperature."
The company eventually installed an
air movement system that would enable it to install only two five-ton air
conditioning units assisted by eight of
these air movers, strategically placed
around the building.
Coenco's (Fayetteville, Ark., www.coenco.com) Positive Air System creates
and maintains a uniform air temperature and low humidity. The system is designed to eliminate the pooling of tempered air at the floor and ceiling.
The amount of supplemental heating and cooling
needed is thereby reduced depending on the tightness of
the building, geographic location, construction materials, density of materials and work activities. Supplemental
heating or cooling is precisely controlled and energy use
can be reduced by up to 70%.
"We put the system in a year ago October, and in the
winter the warehouse became a good work environment
instead of being freezing cold," WerBell says. "It stayed
around 65°F, where in previous years it was in the 40s. It's
a short-sleeve environment year around for the cost of two
air conditioners. In the winter we used ten space heaters.
We can now use two."
Frank Siccardi, the founder of Coenco, says some facilities spend $3 to $4 per sq. ft. on heating and air conditioning. His company's new air moving system operates at
a cost of around $0.25 per square foot, resulting in a system payback of about a year.
"We have a datalogger that takes 38 readings every 30 seconds," he explains. "It tells you how many BTUs
and kilowatt-hours you used for that period. The air
movers are cycling 60 seconds every ten minutes,
which means 2-1/2 hours a day. It's a three-quarter
horse mover, times two and a half hours which gives
you an energy cost of about 10-11 cents a day at 6 cents
a kilowatt-hour."
4. Upgrade Conveyors
Controlling how much energy HVAC systems consume
is a part of the battle, but material handling equipment
can also be made more energy efficient. Poor power factor can act as an energy drain. Inefficient use of supplied
power can often be overlooked because it has few outward signs. There are no blown fuses, tripped circuit
breakers, or failed electrical apparatus to alert plant personnel of a problem.
Induction loads, in particular where motors and transformers are found, along with other devices such as fluorescent lights and variable frequency drives, can use supplied power inefficiently. Take conveyors, for example.
Staco Energy Products (Dayton, Ohio, www.stacoenergy.com) examined the energy use at a 165,000 sq.-ft.
distribution center of a pharmaceutical manufacturer
that relies on many small rated horse-power motors to
power a multitude of conveyors moving product
around the facility.
"We showed the company that by correcting its power
factor it could save from $900 to $1,100 a month," says
Chuck Gougler, manager of business development for Staco. "Once you determine that your utility imposes a
power factor penalty, then you can sit down and rationalize what capacitors can do and figure the return on investment. Generally it's two years or less."
Many utilities offer incentives for the use of such equipment. Working with a specialist in power usage to conduct a facility walk-through and analysis may help identify
other savings opportunities caused by harmonic issues,
the need for surge suppressors, or poor grounding, all of which affect power quality.
Gougler says if a company has a monthly electric bill of
$5,000 or more, savings from power factor correction
can be substantial. He's working with a company in
Texas where the annual power factor penalty is $154,000
per year. Its electric bills range from $1.7 to $2.3 million
annually.
"By spending $10,000 for a capacitor bank versus
$60,000 for a new transformer, I can delay a huge capital
equipment cost two or three years
out," Gougler says. "Even if I do
add that new transformer I'll still
use my capacitors because I want
that monthly savings."
Gregg Vandenbosch, product manager for Dematic
Corp. (www.dematic.com), adds that by combining AC
motors, variable frequency drives and distributed I/O,
conveyor users can add to power factor improvement because: 1) PLC control logic adds a level of intelligence to
energy usage by shutting conveyors down if no load is
sensed; and 2) Variable frequency drives minimize the inrush of current at startup, reducing consumption by making power demand-based.
With newer conveyor technologies that eliminate the
need for compressed air, users can save up to $600 per
horsepower per year, Vandenbosch says. Eliminating a
100 hp air compressor could add up to savings of $60,000
per year.
5. Consider Alternative Energy
From a material handling perspective, conveyors and
sorters are the largest users of energy at Timberland's
(www.timberland.com) 429,000 sq.-ft. distribution center
in Ontario, Calif. But it's the source of that power that's
the big story here.
The distribution center for the designer and marketer
footwear, apparel and accessories, generates 60% of its
electricity needs from a 400-kW solar panel system designed and installed by Northern Power (Waitsfield, Vt.,
www.northernpower.com). Sharp Electronics Corp.
(www.solar.sharpusa.com) manufactured the solar panels,
which resulted in an energy rebate of more than $1.5 million thanks to California's Self-Generation Incentive Program. The setup creates a hedge against potential critical peak pricing surcharges of as much as $1 per kilowatt hour
that may be put into effect in California in future summers.
The material handling equipment at Timberland's DC
is made more efficient with the use of linear induction
motors and an energy management system that shuts
parts of the system down automatically when not in use. If
a conveyor is required, sensors detect incoming cases and
automatically start it up again.
The distribution center helps keep people efficient as
well. The facility is not heated or cooled by traditional
rooftop units. Rather, an air exchange system takes advantage of the cooler evenings in California to keep the
building comfortable during the day. This system monitors the air temperatures. When the outside air is cooler,
roof vents pull warm inside air outside while pulling in
cool air through vents along the outside walls.
The DC's lighting was upgraded in 2003 to reduce
overall lighting energy usage by close to 50%. Metal
halide fixtures were replaced with T5 fixtures that feature "aisle lighter" shields to direct light downward.
Lights in the narrow aisle reserve storage area feature occupancy sensors so they remain off until a lift truck enters the aisle. Low bay lighting was also
converted to fluorescent for additional
energy savings.
Energy is also reduced during the day
with the use of skylights. When sufficient
sunlight is detected, photo sensors turn
off the lights. When there's not enough
illumination, the lights turn back on.
Timberland's manager of environmental stewardship, Betsy Blaisdell, says that facility managers who might want to install such energy saving technology should not assume that contractors are up to
speed on such technology. Her advice is to first reduce
energy usage with more efficient lighting and variable
frequency drives. Second, look into renewable energy
sources (such as solar). Managers interested in solar panels must first make sure the roof is structurally sound to
support the equipment.
Don't forget to explore third-party financing options
for new energy sources, which can deliver instant savings
on utility costs, Blaisdell advises. Because there may be a
waiting list, companies need to sign up early for any state-sponsored rebate programs for renewable energy.
This article has covered ways that light,
heating, air conditioning and conveyors
can be more energy efficient. But here's
the rub: these are cultural changes, not
just investments in new technology.
Where equipment like conveyors is concerned, material handling managers
must take ownership of energy issues as well as functionality. Even maintenance has energy efficiency consequences.
"The big savings in the conveyance world is in managing wear of the roller bearings," says Rob Moyer,
president, PRES Energy (Getzville, N.Y., www.presenergy.com). "The connection isn't always made between
good maintenance and energy expenditures."
That extends to lift truck fleet management, as well. Do
all lift trucks go to work and return for charging at the
same time? Plugging them in simultaneously can cause a
peak in the energy demand and that translates into additional costs. Such factors make energy management
everyone's job.
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Photovoltaic panels on the roof of Timberland's Ontario, Calif. distribution center generate 60% of the facility's power. The solar array is among the 50 largest in the world. |
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