Enter the Xlerator?: Hand Drying at Smith College
Rebecca Keane
May 4, 2005
Smith College
EVS 300
Partner: Kim Wilson
Abstract.
The issue of hand drying may at first seem a mundane, trivial matter unworthy of
any substantial scrutiny or consideration. However, when evaluated with a level of
increased profundity, hand drying becomes a subject deserving of ample, involved
analysis. A closer look at hand drying reveals that it is a task that has environmental
ramifications that are far-reaching and manifold. It is important to try to recognize these
impacts and determine exactly how they effect the environment so that it can then be
decided if the impacts need to be changed through the changing of the basic task: hand
drying. Hence, this project aims to look at hand drying as it unfolds on the Smith College
campus. It explores how paper towel usage at Smith impacts the environment and
compares aspects of paper towel use to those of electric hand dryer use to determine
whether replacing paper hand towels with electric dryers would be more environmentally
friendly. The project also looks at things like the monetary costs of hand drying through
the use of different products and then contends that while the initial cost of replacement
may at first seem daunting, the use of an energy efficient hand dryer would be more
ecologically and economically efficient than the continued use of paper towels both in the
immediate and distant futures.
Introduction.
The simple act of using a paper towel or turning on electric hand dryer effects the
environment in so many ways that they are almost indiscernible and incalculable. Some
of these impacts and the effect they have upon the environment are obvious, such as the
generation of solid waste when a paper towel is thrown out or the consumption of energy
when a hand dryer is turned on. Other impacts, like the energy used and the pollution
2
produced during the making or the transporting of these products might be less
conspicuous and easily gauged. Yet, when it is considered that each day on the Smith
College campus, students and faculty are consistently and frequently drying their hands
with paper towels, throwing them away, creating waste, and virtually consuming all of
the energy used to produce the paper towels, it seems important, perhaps even vital, to try
to identify and quantify these less conspicuous impacts. Doing so could then actualize the
potential for change if the usage of paper towels is found to be a problem because of its
environmental meaning. Alternatives, such as the use of electric hand dryers, can be
investigated through the same criteria and utilized if plausible.
Of course, as previously mentioned, accounting for all of the environmental
effects for something like paper towel and hand dryer usage is nearly impossible. The
impacts have the capability to be so far-flung and voluminous that even merely
identifying them all, never mind quantifying their significance on the environment, could
prove an incessant and epic undertaking. But, with the use of a Product Life Cycle
Analysis [PLCA], this task can be accomplished on some abstract and partial, yet useful
and valuable, level. The PLCA is “…a complicated methodology for identifying the
energy and other resource requirements as well as the environmental impacts associated
with every stage in the life of a product.” (Portney 1993, 69) It resembles a chart or
diagram and seeks to account for things like the pollution generated, the energy used, and
the environmental harm garnered through the processes involved with the product’s raw
material collection, manufacturing, distribution, usage, and disposal. (Portney 1993, 69)
The PLCA is a tool and can be designed, applied to an issue and employed in any way its
user sees fit. The PLCA and the results it helps to find can thus be as abstract and
3
simplistic or as specific and intricate as the user wants, a characteristic of the PLCA that
renders any results found as susceptible to the influences of bias. Despite these latent
shortcomings, for the purpose of examining hand drying at Smith, the PLCA is an
expedient and valuable instrument.
In fact, the PLCA laid the groundwork for this project. After considering the web
of complexity that a simple issue like hand drying can create in the context of
environmental issues and then discovering that the PLCA could be used to tangibly
elucidate this web, we were able to realistically set some goals for our hand drying
project. Essentially, the overall objective of the project is to look at hand drying as it
occurs on the Smith campus today and establish whether it is environmentally hazardous
and should be altered to make it less so. Since Smith uses recycled paper towels as its
primary hand drying mechanism, this meant researching the environmental impacts of
using recycled paper towels generally, applying these implications into Smith’s specific
context in order to determine the footprint that Smith’s paper towel usage forms, and then
exploring whether other means of hand drying, specifically the use of electric hand dryers,
on the Smith campus would create a smaller footprint. To assess the plausibility of
changing over to hand dryers if need be, we also measured and compared the monetary
costs associated with using paper towels and hand dryers.
Additionally, to make our comparisons and thus our findings fully comprehensive,
we decided to compare recycled paper towels with two different types of hand dryers- a
standard model and then a green version. The standard model considered is called the
“Lexan,” and is sold by a company called Excel, which also produces the green dryer we
researched. The green hand dryer is known as the “Xlerator” and is advertised as being
4
three times faster and eighty percent more energy efficient than standard dryers.
(www.exceldryer.com) The Xlerator, which runs for cycles of 10 to 15 seconds rather
than the 30 to 45 time span employed by other dryers, is the only “GreenSpec approved”
and “LEED Certified” hand dryer on the market (Excel Dryer 2004). In terms of this
project, the two hand dryers were hypothetically considered as if being utilized by the
Smith campus and examined in a similar way as were recycled paper towels. All of this
allowed us to compare the usage and costs of the three products and to actualize as the
main conclusion of the project that the most environmentally-sound and energy and cost
efficient hand drying mechanism that Smith could employ would be the green Xlerator
hand dryer.
Methodology.
Initial ResearchThe first steps of our project involved determining how Smith currently deals with
hand drying on campus. This consisted of physically visiting bathrooms and verifying the
specific drying methods employed and interviewing members of Smith’s physical plant
office via email, over the telephone, or in person. Through these interviews we were also
able to ascertain the exact amounts of hand drying materials consumed by the campus on
a monthly basis and the monthly monetary costs of the current system.
A following phase of the project entailed researching general characteristics of
hand dryers. Internet searches proved useful in helping us to decide on which two models
to investigate and gave insight into the conventional monetary and energy costs affiliated
with each product. These facts also enabled us to later calculate the costs of employing
these dryers at Smith and then to compare these figures with the actual costs incurred by
Smith while using its current method.
5
The Product Life Cycle AnalysisSubsequent to completing the initial stages of research, we met with Donna Riley,
a professor in the Engineering Department. She told us of a study one of her classes had
conducted regarding the use of paper napkins versus cloth napkins in campus dining. For
this project, she informed us, her students used the PLCA. After introducing us to the
PLCA, Professor Riley supplied us with some literature on how to construct and use a
PLCA. She then urged us to focus on the end stages of the product’s lives, to discount the
extraction of raw materials and the processes of production and instead focus on the
product’s life after it physically reaches the Smith campus. This would make more sense
because of the fact that the paper towels we were considering were probably going to be
made of recycled materials and because there is a large, seemingly bottomless supply of
recycled paper in the world, the material costs of producing a recycled paper towel are
next to nothing. Eliminating attention paid to the beginning stages of the life of a hand
dryer would problems we would run into regarding the materials used to make a dryer.
Since such materials are only used in producing the dryer once and because they can
probably be recycled after the dryer dies, quantifying such data into our project would be
too figurative and theoretical to be of much use. Professor Riley also referred us to a
study in the book Pollution Prevention for Chemical Processes by David Allen and
Something Rosselot which explains the energy involved in the production and use of a
paper bag.
Much of Professor Riley’s advice proved valuable and applicable to our project.
We read the materials about PLCAs, specifically the report by Paul Portney entitled The
Price is Right: Making Use of Life Cycle Analyses, and contemplated them as we
structured our own PLCAs. Professor Riley’s words regarding the discounting of earlier
6
stages in the product’s life were heeded as well, but only in the case of the hand dryers.
As we went about carrying out our project, we found that in order to compare the energy
consumption engendered by one use of each product, it would be necessary to take into
account the production costs of a singular paper towel as to rightly calculate the amount
of energy used during one paper towel usage. Unlike the hand dryers, whose energy
consumption is clearly corporeal in the amount of electricity needed to run the dryer, a
paper towel does not necessitate the actual consumption of energy, aside from human
energy, when it is used. Paper towel usage does, however, demand the continued
reproduction, transporting, and restocking of paper towel supplies, which are energyconsuming and pollution-producing processes and since they occur on such a frequent
basis should thus be considered in the paper towel’s life cycle. The study by Allen was
also beneficial and we used it to calculate the actual energy used in the production,
dispersal, use, and disposal of paper towels. The study gave us a figure that represented
the amount of energy consumed by the use of a paper bag. This figure was useful in that
because paper bags are similar in physical makeup to recycled paper towels, we could
determine how many paper towels corresponded to one paper bag and use this
comparison and the figure provided by the paper bag study to calculate the actual amount
of energy consumed during one paper towel usage.
Exploring Monetary and Energy CostsNext came a meeting with Brett McGuinness, the Assistant Manager of Building
Services. Mr. McGuinness gave us some solid facts regarding the amount Smith pays per
kilowatt of energy and how many total bathrooms there were in Smith’s administrative
and academic buildings. He also said that the college had priced a rough rate for the buk
purchasing of the Xlerator. We used all of these facts in determining the energy and
7
monetary costs that would be incurred by Smith if it were to adopt hand dryers as its
means of hand drying. After talking with Mr. McGuinness we decided that we should not
consider residential bathrooms in our calculations for physical plant does not currently
supply any sort of drying mechanism in these bathrooms. Mr. McGuinness also
speculated that hand dryers would probably never be put in every public bathroom on
campus but that it is feasible that they could be placed in heavy traffic areas, such as the
campus center or the libraries, and in the new engineering building. We pondered these
speculations when making our recommendations.
Calculating and ComparingUpon performing all of this research, we were able to make some further
calculations, compare our findings, and then decide upon which hand drying method
would be most energy and cost efficient and environmentally friendly if employed at
Smith. We placed the PLCAs of the products, the energy costs, which for the hand dryers
were determined by considering the wattage of energy used per cycle, and the monetary
costs, which were for the hand dryers found by multiplying the amount of hand dryers
needed to stock the Smith campus by the amount of energy used by each dryer by the
amount of money Smith pays for energy, in a side-by-side comparison and were able to
make our final conclusions and recommendations.
Results.
Paper Towel CostsCurrently, in its approximately 350 public bathrooms, Smith uses paper towels
made of 100% recycled materials as its hand drying method. The college uses 68 cases of
paper towels a month. There are 12 rolls of paper towels in each case and 580 towels in a
roll. This means that there are 6,960 paper towels in a case, which in turn means that
8
Smith consumes 473, 280 recycled paper towels monthly. Additionally, each case of
paper towels costs $45.00. Hence, the monetary cost of using paper towels at Smith is
$3,060.00 per month.
The beginning life stages of a paper towel, which is illustrated by the PLCA in
Figure 1 below, generates a lot of pollution and consumes a lot of energy. From the time
the materials to make the paper towel are extracted, to the time that the used paper towel
is transported to a recycling facility, much negative environmental impact is created. This
PLCA is referenced when measuring the energy costs of a paper towel usage and is
useful in imagining the pervasive environmental footprint that a single paper towel can
craft.
Figure 1. The PLCA of a Paper Towel:
Follows the Paper Towel from the forest to the recycling facility where it undergoes the recycling
process.
The life of a recycled paper towel is detailed by the PLCA in Figure 2. This
PLCA begins once a recycled paper towel has reached the Smith College campus. It
9
finishes with the paper towel in the form of waste languishing in a landfill. This PLCA,
like that in Figure 1, is also useful in attempting to fathom the far-reaching environmental
implications of paper towel usage and visualizes the processes considered when
calculating a paper towel’s energy costs.
Figure 2. The PLCA of a Recycled Paper Towel:
Follows the life cycle of a recycled paper towel after it has left the recycling facility.
Allen and Rosselot 1997 indicate that the energy required by the production and
use of a paper bag, including the extraction of raw materials and manufacturing,
transportation, and disposal processes is 1,629Btu per bag. (83) One paper bag represents
approximately 9.75 recycled paper towels. This information can be used to ascertain how
many Btus of energy are used each time a paper towel is used with the following equation:
1629Btu
1 paper bag
X
1 paper bag
9.75 paper towels = 167.07 Btu/paper towel
10
So, one paper towel basically consumes 167.07 Btu per use. For the purpose of
comparison, it is useful to convert Btu to kilowatt seconds:
167.07 Btu
1 watt sec
9.486 x 10-4Btu X 1 paper towel
1 kws
1,000ws X
176122.71 ws
1 paper towel =
=
176122.71watt sec/ paper towel
176.12 kilowattseconds/ paper towel
Now it is known that one paper towel use is equivalent to the consumption of 176.12
kilowatts per second. This represents the energy cost of one paper towel usage.
The Costs of the Lexan Hand DryerThe approximate price of a Lexan dryer, the standard hand dryer we are
considering, is $140.00 each. (www.exceldryer.com) This means to put one in each of
Smith’s 350 bathrooms it would cost about $49,000.00. A typical installation price runs
for around $50.00 per dryer, (exceldryer.com) so that would add another $17,500
bringing the total cost of purchasing a set of dryers for the campus to $66,500.00.
The Lexan uses about 2.3 kilowatts for every second that it runs. Since one cycle
takes from 30-45 seconds, we will use 30 seconds as our variable as to not overestimate
the energy costs. Thus, for every use, the Lexan uses 69 kilowatts per use.
The price Smith pays for energy is $0.05 per kilowatt-hour. It is then useful to use
this number to determine the amount Smith pays for energy per second:
5 cents
1 hr
X
1 hr
60 min X
1 min
60 sec = 0.00138 cents/sec
Then, Smith pays 0.00138 cents for a kilowatt per second. Because a Lexan uses
2.3 kilowatts per second and runs for 30 seconds, every time a Lexan were used on
campus, Smith would pay 0.09522 cents. It is known that Smith uses approximately 473,
11
280 paper towels monthly. If one use of a paper towel is said to be equivalent to the use
of two paper towels (exceldryer.com), then this means that the Lexan would plausibly be
used 236,640 times per month. Therefore, if Smith were to fit the campus bathrooms with
Lexans, the monthly monetary costs would be 22532.8608 cents or $225.32.
The Costs of the Xlerator Hand DryerThe initial price of the Xlerator, the green hand dryer, is a little more than the
Lexan. A bulk purchasing rate runs at about $300 per dryer. So to purchase the Xlerator
for each of the 350 bathrooms, it would cost about $105,000.00. Plus installation price,
the total for fitting the entire campus with Xlerators would be about $122,500.00.
The Xlerator uses 1.6 kilowatts for every second that it runs. The Xlerator’s
typical cycle is 10-15 seconds. Due to the fact that we considered the shorter cycle for the
Lexan, we will do the same for the Xlerator and say that it runs for a total of 10 seconds
per use. So, the Xlerator then utilizes 16 kilowatts per use.
Next, the monthly monetary costs of running of the Xlerator can be found. Smith
pays 0.00138 cents for a kilowatt per second and the Xlerator uses 1.6 kilowatts per
second and runs for 10 seconds. Therefore, every time an Xlerator is used, Smith would
pay 0.02208 cents. If used 236,640 times over the month, Smith would pay 5225.011
cents or $52.25.
Comparing the ThreeThe energy and monetary costs of the three products have been determined. The
energy costs of one usage for the individual products are compared in Figure 3 below.
12
200
180
kilowatts
160
140
120
100
80
60
40
20
0
Recycled Paper Tow el
Xlerator
Lexan
Product
Figure 3. Energy Consumption per Use:
Each use, a recycled paper towel uses 176.12 kilowatts. The Lexan uses 69
kilowatts and the Xlerator 16.
Figure 4 compares the monthly monetary costs of each product as determined by
our research.
3,000.00
Dollars per Month
2,500.00
2,000.00
1,500.00
1,000.00
500.00
0.00
1
Recycled Paper
Towel
2
3
Lexan
Xlerator
Product
13
Figure 4. Monthly Monetary Costs:
Smith spends $3,060 on paper towels monthly. The Lexan would cost $225.32 to run monthly and
the Xlerator $52.25
Discussion.
The green Xlerator is clearly the most efficient and advantageous hand drying
system and should be adopted by the Smith College campus. It is far more energy
resourceful and less costly than both recycled paper towels and the standard Lexan dryer.
The current system which Smith uses, that of stocking all of the restrooms solely with
paper towels, seems inefficient when considering what goes into producing and
transporting the towels each time they need to be restocked. The energy consumed and
the pollution produced even before the paper towels arrive at Smith seem to be too
exorbitant and environmentally-taxing to make the use of paper towels worth it. In
addition, the almost half a million paper towels used and then thrown away monthly
undoubtedly create tons of solid waste. There are also other issues associated with their
disposal, such as the use of garbage bags and the need for man power that effectively to
lessen the overall utility of paper towels when considered comprehensively.
Although the life cycle of a hand dryer probably harbors many problematic
environmental impacts as well, this life cycle is commenced far less frequently, perhaps
only 350 times, compared to the life cycles of paper towels, which are stimulated over
400,000 times a month. In other words, all of the environmental repercussions of a hand
dryer do not occur every time the product is used, whereas with a paper towel, they do.
One environmental drawback that does occur with each hand dryer use is the
consumption of electricity, which brings with it the expelling of emissions and the
production of pollution. Yet, the energy efficiency of the Xlerator minimizes the wasteful
expenditure of electricity. Another negative aspect of adopting hand dryers at Smith
14
could be the potentially discouraging initial purchasing and installation prices. But, when
it is seen how much more cost-effective the Xlerator is on a monthly basis when
compared to recycled paper towels, it seems logical that the money lost with installation
would be compensated for in a matter of a few years.
Mr. McGuinness of physical plant offered that it is not realistic that Smith would
replace paper towels with the Xlerator in all of its bathrooms. In light of the findings of
this project, this speculation can at first seem disheartening. However, there is a sense of
optimism imbued with that it is possible that Xlerators could be placed in heavy traffic
areas. Since these restrooms attract more patrons, it would logically follow that hand
drying within these particular rooms consumes more energy monthly than restrooms in
less trafficked areas. Consequently, removing paper towels from the popularly visited
bathrooms and installing Xlerators would still manage to cut down on energy and
monetary costs than the continuation of the current system. What’s more, the construction
of the new engineering building offers further auspiciousness. It will be a LEED certified
building. It would make sense to place within it the only LEED certified hand dryer, the
Xlerator, and it is a strong recommendation of this project that this be done. If the
Xlerator proves a popular hand drying mechanism in the novel new engineering building,
perhaps it could gain a level of esteem that would propel its spread into other buildings
and into other bathrooms all around campus. Hand drying is a process that has the
potential to be largely environmentally hazardous. With the use of the Xlerator, however,
this potential is substantially lessened.
15
Works Cited
Allen, David T. and Rosselot, Kirsten Sinclair. Pollution Prevention for Chemical
Processes. New York, NY: John Wiley & Sons, Inc., 1997. pp. 79-90.
Portney, Paul R. “The Price is Right: Making use of Life Cycle Analyses.” Issues in
Science and Technology Winter (1993-1994): 69-75.
Excel Dryer. “Finally…A Fast Hand Dryer.” Excel Online. 2004. Excel Dryer. Viewed
12 April 2005 <http://www.exceldryer.com/>.
16