Going Green - Ceramic Arts Daily

GoinG
Green
Artists Tap Alternative Resources to Fuel
Their Creative Pursuits
by Jon Ellenbogen
Ceramics Monthly December 2007
28

focus sustainability
Opposite: At EnergyXchange, in Burnsville, North Carolina, landfll gas—collected by an underground system of vents that feed
an above-ground distribution valve—is used to fre kilns and glass furnaces, and to heat the work spaces.
Above: The open, shared ceramics studio at EnergyXchange is meant to encourage not only effcient use of space, but effcient
use of intellectual and creative ideas. Residents are meant to work together to solve technical and creative problems.
Yancey and Mitchell Counties comprise a rugged, rural area in the
northwestern corner of north Carolina. one would think that
visitors to this beautiful Black Mountain range would be unlikely
to make a stop at the old Yancey-Mitchell County landfll, but
thousands of people have happily done just that over the last several
years. on a small campus built just beside the now-closed landfll, an
organization called energyXchange has built two craft studios and
four greenhouses that utilize the continuous supply of landfll gas
to fre kilns and furnaces and to heat the buildings. This visionary
project, conceived in 1997 and opened for use at the end of 1999,
has served as one of the nation’s model energy recovery projects for
small rural landflls.
The campus features a horticultural component and a crafts
component. The horticulture portion includes four greenhouses
and three cold frames for the production of endangered native orna­
Ceramics Monthly December 2007
29
mental plants such as rhododendron and mountain laurel, with the
greenhouses heated by landfll gas. The crafts component comprises
a clay studio housing four pottery residents, a glass studio with two
residents, a visitor center and a retail gallery space. naturally, all
the buildings are heated with landfll gas and the kilns and furnaces
use the gas as well.
The CrafT residenCies
The craft residencies at energyXchange represent a rare opportunity
for talented and promising craftspeople to launch their careers as
working artists. The program is designed as a small business incubator.
The craft artists in clay and glass are selected by media-specifc
juries for three-year terms. in return for modest rent, they receive
a shared space in a fully equipped studio, access to the gallery and
business center and use of the landfll gas at no additional cost. As

LandfiLL Gas and aLternative fueLs
engineering studies have predicted about twenty years of gas
production from a typical landfll. For a project such as energyXchange,
the savings in fuel costs for the resident artists
and greenhouse activities at the site could total approximately
$2 million. naturally, the majority of this is attributable to
the high energy demands of the glass studio.
Signifcant cost savings can be realized by potters without
access to a landfll through a variety of strategies and fuel
choices. These can be divided into categories and discussed
fueL
deLivery
& storaGe
Burner systeM
Heat density
carBon iMpact
in terms of benefts and diffculties. Solid fuels are diffcult,
liquid fuels are moderate, and gases are easier.
solid fuels
Besides traditional wood firing, numerous attempts have
been made to use sawdust to fuel kilns. This fuel occupies
large volumes, needs to be delivered to the site of the kiln,
must be kept dry, and has to be fed to the firebox in a con­
tinuous and controlled manner. it’s the delivery system to the
firebox that generally proves to be difficult. Professor Lowell
Baker at the University of Alabama Art Department has de­
veloped a sawdust injection system. information is available
on his research page at http://bama.ua.edu/~wbaker/Main.
Another source of information is the book Handbook of
Ceramics Monthly December 2007
30
Homemade Power, published by Mother earth news, and
available on Amazon.com.
Liquid fuels
Many potters are utilizing a variety of liquid fuels such as
french fry oil from restaurants, crankcase drain oil from automobiles
and home heating oil. The simplest confgurations
can be described as drip systems, in which one of these liquids
is dripped in a fne stream directly into a propane or natural
aLternate and renewaBLe fueLs for potters
soLid Liquid Gas
Sawdust Oils Landfll Gas,
Compost Gas
Manufactured
Gas
Propane,
Natural Gas
Diffcult Collected by User Complex Simple
Complex Drip: Simple
Atomized: Complex
Complex Simple
Low Moderate to High Low High
High High Low Moderate
gas burner fame, thus boosting the heat delivered to the kiln.
Such systems are simple and inexpensive to build but require
constant monitoring during use. Combustion is incomplete
(possibly good for reduction frings) and therefore likely to
contribute to global warming and cause some air pollution.
Burning crankcase drain oil likely presents environmental
hazards and cannot be recommended.
For effcient burning, liquid fuels must be precisely atomized
and require complex mechanical pump-driven burner
systems. Bakersville, north Carolina, potter Kent McLaughlin,
among others, is successfully using an electrically driven
mechanical burner to supplement a propane-fred Cone 10
reduction kiln with fry oil he collects from area restaurants
(see “French Fried Pots” on page 32). Fry oil must be gath

ered, screened and preheated before it can be used in a pressure
burner system. Though it is “free” right now, supplies will become
squeezed as biodiesel fuel becomes more common.
Gaseous Fuels
Manufactured gaseous fuels remain the most practical for potters.
Propane and natural gas are simple to store and to deliver, burn
efficiently with inexpensive burner systems, and are generally
trouble free. Renewable gaseous fuels, with landfill gas being only
one source, present greater challenges. Composters can be constructed
on almost any scale and the resulting gas utilized much
like landfill gas, with the major challenge being the complexity
of collecting compostable materials on a sufficiently large scale
and the difficulty storing such gas production. Currently only
municipalities can deal with composting on a scale sufficient to
result in usable gas production.
Other Cost-Saving Strategies
Many studies have shown that lowering the firing temperature
of a typical glaze firing from Cone 10 to Cone 5 could save
25-35% in fuel costs while reducing the impact on the planet.
Consequently, such an adjustment would be both a socially
responsible and economical choice.
Heat recuperation is another approach to fuel savings. This
involves a heat exchanger built into the flue or chimney of a kiln
to use the heat of the escaping flue gases to preheat the combustion
air. Such processes are widely used in industry but not normally
considered by studio artists. Interesting work is currently
underway in Hawai‘i by glass artist Hugh Jenkins (see “Volcano
Kiln” on page 36). Since propane in Hawai‘i currently costs $3.20
per gallon the incentives for recuperation are obvious.
Landfill Gas Energy Projects Nationwide
410 Operational Landfill Projects
575 Candidate Landfills
tO Learn mOre . . .
If you are interested in starting a landfill partnership
project in your area, visit the Environmental Protection
Agency’s Landfill Methane Outreach Program website
at www.epa.gov/lmop.
Ceramics Monthly December 2007
31
focus sustainability
Lady Vase, 9 in. (23 cm) in height, stoneware, fired to Cone 10 in reduction,
$65; by Lindsay Rogers, EnergyXchange resident, Burnsville, North Carolina.
an added benefit, the craft artists receive small business training
classes, which are provided on site and totally free. The six
resident artists share the job of staffing the gallery, greeting
visitors, and handling sales of the work. Because the site has
attracted numerous people and tour groups, the residents have
enjoyed excellent sales from more than 5000 annual visitors.
All of the residents are free to participate in the community
activities of nearby Penland School of Crafts, a significant
source of stimulation, ideas and contacts.
Shared StudiOS
The four potters who share the clay studio have discovered
numerous benefits beyond the obvious use of the building
and equipment. No potter makes continuous use of kilns,
extruders, slab rollers and the like, so little compromise results
from sharing such items. But the residents at EnergyXchange
identify their greatest benefit as the sharing of ideas, skills and
experiences. They have found that working in a group setting
helps them resolve production challenges, aesthetic problems
and business difficulties. Each resident can leverage his or her
skills through the experiences of the others, thereby making
progress along a career path that would have taken longer if
operating solo.
Perhaps the lesson learned from this experience is that, in
the post-modern world, the idea of the artist working alone in

i am fortunate to live in a very rural area that has several din­
ers that use vegetable oil to fry several of the menu entrées.
initially, i placed a 30-gallon plastic barrel outside one such
diner that had agreed to save the used oil for me. My plan
was to swap out the barrel every fve weeks (the owner
predicted it would take that long to fll the
barrel) and
replace it with an empty 30-gallon barrel.
i learned two facts immediately: First, i
fow valve
couldn’t lift the full barrel of oil onto
the back of my pick-up truck.
Secondly, used, hot oil will
melt plastic barrels.
i modifed my plan by pur­
oil gravity feed from
chasing a manual bilge pump from
storage drum
West Marine (model # 2845519,
$36.99) and simply pumped the oil into
an empty barrel on
the truck. once the oil was home, i used
5-gallon buckets to
offoad the oil into larger barrels for later
processing.
After searching for other sources of
oil, i found a diner that
replaces the used oil back into the original
small plastic jugs
that it came in. The smaller containers
eliminated the need for
the bilge pump and barrels and greatly
simplifed the gathering
process. Before using, the oil requires
fltering to remove any
All Carbon is not Equal
A few years ago, when I seriously began to explore this
fuel for the kiln, I came across a student’s masters thesis
dealing with vegetable oil. A portion of the discourse dealt
with poly-unsaturated and saturated oils used in cooking.
Further searching led me to a way more information than
I wanted or needed. The one thing I learned was that these
fuels have more carbon atoms in their molecules than pro -
pane. This also coincided with my carbon trapping shino
glaze period. I thought the two would be a perfect match.
I discovered that although there may be more carbon
atoms in the oil molecules, the bond between the carbon
atoms seemed to be much stronger, freeing up less carbon
to trap on the shino glaze. The initial frings produced very
little carbon trapping. Now, I fre the kiln using oil and with
the propane burners throttled way back and the primary air
almost closed to help create a reducing atmosphere. I’m
very happy with those results.
frencH fried pots
by Kent McLaughlin
air inlet grate
Ceramics Monthly December 2007
32
oil drip tube
The turbine pulls air
in through the back
of the burner and
forces it out the front
around the atomizing
nozzle.
The brass atomizing
nozzle spins
with the turbine at
a high speed, and
uses centrifugal
force to atomize
the oil as it exits
through the front
of the nozzle.
food particles. My flter is a homemade porcelain bowl
(14½ inches wide × 5 inches deep) intended to be a sink
with a 2-inch drain hole in the bottom. it fts perfectly over
a 5-gallon pail. i used JB Weld to glue a 40-mesh stainless
steel screen over the hole to act as a flter. When the pail
is about half full of the fltered oil, i then pour it into my
55-gallon drum. The fltering/pouring process continues
until the 55-gallon drum is about three quarters full. This
ensures that there is plenty of fuel for the fring.
once the kiln is preheated with propane to Cone 012,
the oil burner is placed into its burner port and started.
The heat in the kiln will ignite the oil. i use around 25
gallons of oil when i fre the kiln. The BTU rating on fry
oil is approximately one and a quarter times that of pro­
pane so i estimate a savings of about 30 gallons of propane
per fring. My frings are in the Cone 10+ range. The fuel
cost savings are just a part of this equation. Some of my
other considerations are renewability, sustainability, using
a domestic fuel source and environmental concerns.
Kent McLaughlin will be teaching a course on vegetable
oil fring at Penland School of Crafts in Spring 2008. For
more information, visit www.penland.org.

sHare and sHare aLike
Though hard to quantify,
the cost benefts of shared
studios include the following:
• One fully equipped studio serves four
potters—one structure means one
utility bill, one telephone bill, one
heating bill, etc., split four ways
• Shared materials purchases with
resulting discounts
• Shared cost of equipment maintenance
when required
• One gallery space with shared
monitoring responsibilities
• Visitors come to the gallery for multiple
purposes, resulting in leveraged
visibility for each potter
• Shared computers, fax, copier, Internet
account and credit card terminal
an individual studio is becoming obsolete and that
cooperative studio settings could be the way of the
future. Think of the diminished environmental
impact of fewer buildings, reduced use of materials
and smaller infrastructure demands.
COLLeCTinG The Gas
At energyXchange, landfll gas is collected by wells
that are drilled down from the surface nearly to
the bottom of the landfll. These wells are simply
perforated plastic pipes that have been placed into
the center of four-foot diameter holes lined with
crushed rock. The decomposing garbage produces
gas that is drawn into the pipes, which are con­
nected via manifolds to an electric blower that
pushes the gas to the buildings and studios where it
will be used. The six-acre landfll at energyXchange
used six wells initially, but several more have been
added in recent years.
There are more than 900 other small rural
landflls in America that could be converted to
energy sources, and energyXchange has inspired at
least thirteen similar projects throughout the US.
Large landflls can produce prodigious quantities of
landfll gas, and the BMW automobile factory in
Spartanburg, South Carolina, is currently utilizing a
300-acre landfll to meet all of its natural gas needs.
The University of north Carolina at Asheville is
Carved Vase, 2007, 10 in. (25 cm) in height, thrown, altered and
carved porcelain, fred to Cone 10 in reduction, $140; by Emily
Reason, EnergyXchange resident, Burnsville, North Carolina.
Ceramics Monthly December 2007
33
focus sustainability

oHio vaLLey creative enerGy:
turninG trasH to treasure
Similar in mission to energy Xchange, ohio Valley
Creative energy (oVCe) is a grassroots, nonproft
organization based in the Louisville, Kentucky,
region. oVCe is currently in the planning stages of
designing and building an effcient and innovative
green building to house “fre art” studios powered
by landfll gas and other renewable sources at the
Clark-Floyd Landfll area in Southern indiana.
oVCe plans to use waste heat to power a small
refnery that will produce biodiesel to power shuttles
for artists and tourists, and the dump trucks that un­
load at the landfll. They also plan to recuperate waste
heat so that it takes less fuel to power equipment and
heat offce/community spaces
and greenhouses.
“everything we do—
from studio design to
equipment and systems
technology (see “Volcano
Kiln, Page 36), architectural
design and planning
to energy use—will take
ecology into account,”
says oVCe project direc­
tor/founder Lori Beck.
“A carbon budget will be
balanced with a monetary
budget. We hope to pro­
vide insight and reason
for all visitors and artists
to consider shifting to a
more green lifestyle.”
The oVCe project
is the frst community/
commercial landfll gas
partnership. in addition
to fnancial support, Hoo­
sier energy, the major
corporate partner, will run a two mega watt electricity
generation station that will provide green power to area
consumers and donate all excess power to oVCe.
“This is important because it sets a standard for
the rest of the industry, making the commercial end
users more aware of the potential community uses
of this resource. This is about community working
together, and holding corporate America account­
able. This is a good sign.”
Green studio HaBits
Architect Doug Pierson of (fer)—form environment research—
studio, a progressive design studio located in Los Angeles,
California, is working with OVCE to design all the buildings,
including the “fre arts” studios. Pierson offers this advice for
designing a green studio space:
• Design an open foor plan. Several sectioned rooms create
many microclimates, which can overwork heating and air
conditioning. Multipurpose space means you need less space.
• Use rapidly renewable materials (those made from
living things with a life cycle of ten years or less). Bamboo,
wheatboard (similar
to medium density
In addition to Pierson ’s recommendations for studio
design, here are some steps you can take to lessen your
environmental impact:
• Recycle all raw clay (or even dig your own clay)
to reduce the amount of mined, packaged and
shipped material.
• Save reject bisqueware and crush it into grog. This
is particularly useful when you don ’ t want
your fnished
pieces to have the grog color show through.
• If you have a garage studio with no running water,
a graywater (rainwater) collection system can provide
the water you would otherwise haul from your house,
thereby reducing the amount of water that needs to be
treated. If you need hot water in the studio, a tankless
water heater could be used.
• Use an oxygen probe to ensure you fre as effciently
as possible (see “Striving for Perfection” on page 37).
• Consider fring with waste vegetable oil (see
“French-Fried Pots” on page 32).
34
fberboard, or mdf)
and sunfower seed
board can be used
instead of gypsum,
meaning less mining
of raw materials.
• If you use
wood, check to see
if your local lumber
company stocks
Forest Stewardship
Council certifed
lumber. This is
typically veneer
plywood and solid
hardwoods.
• Purchase tradeable,
renewable
energy certifcates
(RECs). Calculate
the amount of
energy your studio consumes (in kilowatt hours), and purchase
that much energy or renewable energy certifcates.
To learn more about renewable energy certifcates, visit
www.eere.energy.gov/greenpower.
• Use low-voltage, compact fourescent or LED (light
emitting diode) fxtures. LED technology now includes replacement
bulbs for traditional incandescent A-type fxtures.
Ceramics Monthly December 2007

currently designing an ambitious crafts campus adjacent to
the city’s landfll, to utilize that gas and other “green” energy
sources. in addition, ohio Valley Creative energy in Borden,
indiana, (near Louisville, Kentucky) is in the development
stages of a green arts center (see opposite page).
LandfiLL Gas ChemisTry
Landfll gas results from the decomposition of organic matter
in the buried garbage in a landfll, provided there is suffcient
moisture. Though the gas composition can vary from place
to place (and even from day to day) it is typically about 55%
methane, 40% carbon dioxide and 5% other gases. The landfll
gas is lighter than air and will escape into the atmosphere, or
it can be collected through a series of horizontal or vertical
pipes, or wells.
Methane is known to be a greenhouse warming gas, so the
release of methane into the atmosphere is harmful to the planet.
Burning the methane in an open fame results in carbon dioxide
and water vapor. Though carbon dioxide is also a greenhouse
warming gas, methane is about 21 to 25 times more harmful,
so combustion of the landfll gas is benefcial. According to
an ePA feasibility study, the benefcial environmental impact
of the Yancey-Mitchell County Landfll Project is equivalent
to planting 14,000 acres of trees or taking 21,000 cars off the
road in north Carolina.
firinG WiTh LandfiLL Gas:
free, BuT nOT easy
Compared to propane or other gaseous fuels, landfll gas has a
low heat content—think of it as half-strength natural gas. in a
landfll, gas is generated continuously but at very low pressure,
so large volumes must be delivered to a kiln or furnace through
large diameter piping and blower systems. This requires a kiln
designed for greater volume fowing both in and out.
Secondly, it is corrosive, so metal parts in contact with
the gas must be monitored and replaced continuously, even
if they are stainless steel. Thirdly, it will not sustain a pilot
light nor can it be ignited by spark, so standing pilots must
be propane or natural gas powered. it should be mentioned
that in a small, rural landfll it is not cost effective to store the
gas that is produced continuously, nor is it practical to purify
it. Consequently any excess (above the amount in use by the
facility) is burned in an open fame, with the benefts to the
planet mentioned above.
Because of its lower heat content, kiln frings always take
longer than with other fuels and require more attention
throughout. Gas production varies with time of year, weather,
and even time of day, and “fring by formula” is not practical.
Because of lower heat input to the kiln it is prudent to reduce
any heat losses, so the kiln is surrounded by an effective wind­
break and is extra-well insulated.
For more information, please visit www.EnergyXchange.org or
contact executive director Heather Dawes at (828) 675-5541.
35
focus sustainability
Vase, 13 in. (33 cm) in height, glazed stoneware, $80;
by LeAnne Ash, EnergyXchange resident, Burnsville, North Carolina.
Ceramics Monthly December 2007

HuGH Jenkins’ voLcano kiLn:
recuperatinG waste Heat for efficient firinG
As a studio artist, it is often hard to spend large sums of money, even if doing so
would pay off in the long run, so glass artist Hugh Jenkins set out to determine just
how well he could do with a home-built heat recuperator. After several improvements,
he discovered that, depending on how much fuel he used, recuperating
hot air in a closed system can reduce fuel consumption by up to 80%. He then
applied what he learned when helping a friend build a kiln for ceramics. one of
the biggest factors in the performance of these units is a very tight-ftting door.
Any gaps can signifcantly cut the effciency of the heat exchanger.
Hugh Jenkins is working with OVCE (page 34) on sustainable
equipment design. He is available for workshops, and further
information can be found at www.bigislandglass.com.
1. The recuperator is installed at the top
of the stack and consists of a mullite tube
that carries the kiln exhaust, surrounded
by a metal tube that is several inches
larger in diameter than the mullite tube.
This forms a cylindrical channel that is
open at the top, through which outside
air enters the system. The air is heated
by the mullite tube and is pulled down
into the primary air channels in the brick
stack and kiln wall.
damper blade
between fue
stack and
exhaust tube
2
3
compressed air
blows through a
venturi carved into
the soft brick
1
1
2.
The chimney is a doublewall
structure. Flue exhaust
travels up the center to the heat
exchanger, and heated air from
the exchanger travels down the
outer chamber to the primary
air channels in the back wall of
the kiln. Air is drawn through
the sytem by compressed air
(3) at the bottom of the stack.
4
arrows indicate
recuperated
heat fow
fue
opening
4. The burner blocks are made of
castable
refractory. The bottom hole
is for a pilot burner, and the top
houses the main venturi burner.
Each fts into the block exactly,
so that the only air used is the
recuperated, heated air delivered
through the primary air channels,
which
are cast into the blocks. When
set into the kiln wall, the vertical
channels on the sides of the blocks
connect to the channels in the kiln
wall. From the vertical channels air
enters the burner tube at an angle,
creating turbulence in the burner
tube, encouraging complete air/gas
mixture. Each natural-draft burner
has an air control on the back, but
they remain closed.
Ceramics Monthly December 2007
36
2
2
1
3
mullite exhaust tube
stainless steel heat
exchanger shell
4
cast
burner
block
3. Compressed air is
introduced into a venturi
opening at the base of the
recuperation system. This
serves not only to pull air
into the system from the top
of the heat exchanger (1),
but also to push the heated
air through the channels to
the burner blocks (4).
4