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Redesigning the Office Redesigning the Office Chair Chair –– Part 2Part 2

ENGS 171ENGS 171

May 27, 2004May 27, 2004

by Brian by Brian HenthornHenthorn

and Charles Pahland Charles Pahl

PREVIOUS ENVIRONMENTAL PREVIOUS ENVIRONMENTAL ASSESSMENTASSESSMENT

�Average Office Chair weight: 20.53kg*

�Our chair Royal Blue Global Armless Task Chair, carried by Staples Inc, and of which there are over 20 at the Thayer School: 11.4kg

�2.2kg of packaging on average

*US Environmental Protection Agency, Solid Waste and Emergency Response, Municipal Waste Reduction Branch, Waste Wise Update: The Measure of Success Calculating Weight Reduction (Washington, DC: 1999) 11. <http://www.epa.gov/wastewise/pubs/wwupda11.pdf>.

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PREVIOUS ENVIRONMENTAL PREVIOUS ENVIRONMENTAL ASSESSMENTASSESSMENT

333,987.001,004,778.0411.40Total

9,632.009,632.00--60,200.000.16Hydraulic Oil

8,587.4915,083.9442,300.0074,300.000.20Fabrics (Olefin, PP)

160,682.74259,758.4344,600.0072,100.003.60Plastics (polyurethane)

6,573.8221,912.7415,900.0053,000.000.41Zinc

73,205.34532,146.4926,000.00189,000.002.82Aluminum

75,225.61166,244.4418,100.0040,000.004.16Steel

Chair Energy (Recycled) (kJ)

Chair Energy (Virgin) (kJ)

Energy Required -Recycled (kJ/kg)

Energy Required -Virgin (kJ/kg)

Our Office Chair (kg)Material

Replace table with newer one

PREVIOUS ENVIRONMENTAL PREVIOUS ENVIRONMENTAL ASSESSMENTASSESSMENT

12,254,387.0536,875,354418.38Total

353,494.40353,494.40--60,200.005.87Hydraulic Oil

315,160.96553,580.6042,300.0074,300.007.45Fabrics (Olefin, PP)

5,897,056.719,533,134.2844,600.0072,100.00132.22Plastics (polyurethane)

241,259.22804,197.4015,900.0053,000.0015.17Zinc

2,686,635.9019,529,776.326,000.00189,000.00103.33Aluminum

2,760,779.856,101,170.9418,100.0040,000.00152.53Steel

Total Energy (Recycled) (kJ)

Total Energy (Virgin) (kJ)

Energy Required -Recycled (kJ/kg)

Energy Required -Virgin (kJ/kg)

Annual Quantities (million kg)Material

Replace table with newer one

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Energy HierarchyEnergy Hierarchy

Making Materials

Transport Assembly Disassembly

EnergyEnergy

�� Annual Values range between 12.3Annual Values range between 12.3--

36.9 GJ36.9 GJ

�� Total Energy to produce one chair Total Energy to produce one chair

ranges: ~334ranges: ~334--1005 MJ1005 MJ

(recycled or not)(recycled or not)

��Calculated assembly: 14,500kJCalculated assembly: 14,500kJ

–– Agreeing with hierarchy of energyAgreeing with hierarchy of energy

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TRANSPORTATION COSTSTRANSPORTATION COSTS

�� Plays a significant Plays a significant

part to part to

environmental environmental

impactsimpacts

TRANSPORTATION COSTSTRANSPORTATION COSTS

Shipment Characteristics by Mode of Transportation, US (percent of total tonnage)

Truck

Rail

Water

Air

Pipeline

69.1%

By the American Trucking Institute

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Truck 7622257 65.9

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TRANSPORTATION COSTSTRANSPORTATION COSTS

�� 7.6 Billion Tons = 6,895Tg7.6 Billion Tons = 6,895Tg

�� Lower Bound:Lower Bound:

13.68kg/chair * 36.7Mchairs = 502Gg13.68kg/chair * 36.7Mchairs = 502Gg

��Upper Bound:Upper Bound:

22.75kg/chair * 36.7Mchairs = 835Gg22.75kg/chair * 36.7Mchairs = 835Gg

��US Truck Shipment: 0.0073US Truck Shipment: 0.0073--0.012% 0.012%

Transportation PollutionTransportation Pollution

0.04780.40930.47670.00150.002135.350

Office chairs (upper bound, Gg)

0.02880.24610.28660.00090.001221.252

Office chairs (lower bound, Gg)

0.05730.49020.57080.00170.002542.335

g emission per kg shipped

3953,3803,9361217291,900Total (Gg)

NMVOCCONOxN2OCH4CO2

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Transportation PollutionTransportation Pollution

�� Difficult to compare Difficult to compare

energy to emissionsenergy to emissions

�� Study of Power plant Study of Power plant

guidelines set NOx guidelines set NOx

emissions at 86emissions at 86--

260ng/J260ng/J

�� Pie chart compares Pie chart compares

using this using this

conversion between conversion between

energy & pollutantenergy & pollutant

Percentage of Estimated Total NOx emissions (Gg)(Using the Upper Bounds)

Production

Assembly

Transportation

REDESIGN PROCESSREDESIGN PROCESS�� DeepDeep

�� Moderate/DeepModerate/Deep

Product change Benches/couches

Product change No need for height adjustments -several chairs w/ different heights

Transport reduction Localized production/sale

Product change Integrating chair into desk - no separate chair unit

TYPETYPEALTERNATIVESALTERNATIVES

Product change Air hockey table floor - no need for wheels

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REDESIGN PROCESSREDESIGN PROCESS�� ModerateModerate

Dematerialization Replace foam with air

Design for disassembly/extend product lifetime

Detachable fabric - wears out quickest

Transport reduction Fleets use alternative fuels

Design for disassembly Alternative height adjustment (pin/notch, springs, screw)

Dematerialization Redesign wheel-system

Design for reuse Service-lease chairs or components

REDESIGN PROCESSREDESIGN PROCESS�� Shallow/ModerateShallow/Moderate

�� ShallowShallow

Dematerialization Honey comb plastic

Design for Recycling Plastics identification

Design for Disassembly Plastic clips instead of staples and screws

Design for RecyclingEnvironmental friendly fabric

Design for Disassembly Replaceable wheels

Using a uniform plastic/nylon for entire chair

Design for Recycling

DematerializationMolded butt and back together

Design for recyclingLabeling each type of material

DematerializationReducing materials (cardboard) by stamping info on plastic

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REDESIGN PROCESSREDESIGN PROCESS

�� Deep Solutions are infeasible & Deep Solutions are infeasible &

need societal changeneed societal change

�� Lease possible with companiesLease possible with companies

�� Redesign wheelsRedesign wheels

�� AlternativelyAlternatively--fueled fleetsfueled fleets

Selected AlternativesSelected Alternatives

Dematerializationshallow/moderateMolded butt and back together

DematerializationmoderateReplace foam with air

Design for disassembly/extend product lifetimemoderate

Detachable fabric - wears out quickest

Design for recyclingshallow/moderateLabeling each type of material

Design for recyclingshallowPlastics identification

Design for disassemblymoderateAlternative height adjustment -nylon screw

Design for disassemblyshallowNylon screws for fasteners instead of steel screws

Dematerializationshallow/moderateReducing materials (cardboard) by stamping info on plastic

Design for recyclingshallowUsing a uniform plastic/nylon for entire chair

TYPESCOPEALTERNATIVES

Maybe insert highlight above for what investigated

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ImplementationImplementation

�� Eliminating Cardboard PanelingEliminating Cardboard Paneling

–– Though already use 100% recycled, can Though already use 100% recycled, can

stamp information into plastic insteadstamp information into plastic instead

Height Adjustment RedesignHeight Adjustment Redesign

�� Seat HeightSeat Height

–– PinPin--Notch Notch

SystemSystem

��Requires difficult Requires difficult

removal of loadremoval of load--

bearing pinbearing pin

–– SpringsSprings

��Height controlled Height controlled

by user weight by user weight

–– ScrewScrew

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Seat Height Seat Height ImplementationImplementation

�� ScrewScrew

––Have the support rod be a Have the support rod be a

large screw that winds into the large screw that winds into the

base for height adjustmentbase for height adjustment

Air CushioningAir Cushioning��Uses air as a Uses air as a

substitute for foamsubstitute for foam

�� Encasing plastic is Encasing plastic is

PolyPoly--Vinyl Chloride Vinyl Chloride

(PVC)(PVC)

--Create different pockets Create different pockets

for ergonomicsfor ergonomics

Plastic Frame

Air Cushion

Fabric Cover

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Molded Seat and BackMolded Seat and Back

�� Eliminates need for steel connecting Eliminates need for steel connecting

barbar

Alternative FastenersAlternative Fasteners

�� Replace metal screws inlaid into plastic frame Replace metal screws inlaid into plastic frame with nylon screws into nylon framewith nylon screws into nylon frame–– Allows for easier recyclability and disassemblyAllows for easier recyclability and disassembly

�� Replace staples connecting fabric and plastic Replace staples connecting fabric and plastic frame with elastic band on edge of fabricframe with elastic band on edge of fabric–– Allows for easy detachment of fabric backing for Allows for easy detachment of fabric backing for recycling/disposal/replacementrecycling/disposal/replacement

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Design for RecyclingDesign for Recycling

�� Use uniform plastics throughout chair Use uniform plastics throughout chair (Nylon or alternative)(Nylon or alternative)

�� Label plastics with corresponding number Label plastics with corresponding number to aid recyclingto aid recycling

�� Label composition of all materialsLabel composition of all materials–– may have proprietary issuesmay have proprietary issues

Recalculated Material CompositionRecalculated Material Composition

5.5011.40Total

0.250.25Other

5.243603.001.003.60Plastics (polyurethane)

0.0059.007.000.41Zinc

0.001042.962.702.82Aluminum

0.00539.508.004.32Steel

Redesigned Office Chair

(kg)Volume (cc)Densities

(g/cc)

Original Office Chair

(kg)Material

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Recalculated Production EnergyRecalculated Production Energy(per chair)(per chair)

359,143.5581,7938.11Total (upper bound)

242,291.5392,8885.49Total (lower bound)

8,587.515,08442,30074,3000.203Fabrics (Olefin, PP)

350,556566,70944,60072,1007.86

Plastics upper bound (polyurethane)

233,704377,80444,60072,1005.24

Plastics lower bound (polyurethane)

Chair Energy (Recycled) (kJ)

Chair Energy (Virgin) (kJ)

Energy Required -

Recycled (kJ/kg)

Energy Required -

Virgin (kJ/kg)

Redesigned Office

Chair (kg)Material

Recalculated Production EnergyRecalculated Production Energy(Annually)(Annually)

13,180,566.1621,351,690.8295.913Total (upper bound)

8,892,097.76314,418,987.4199.759Total (lower bound)

315,160.9627553,580.60442,30074,3007.451Fabrics (Olefin, PP)

12,865,405.220,798,110.244,60072,100288.462

Plastics upper bound (polyurethane)

8,576,936.813,865,406.844,60072,100192.308

Plastics lower bound (polyurethane)

Total Energy (Recycled)

(GJ)

Total Energy (Virgin)

(GJ)

Energy Required -Recycled (kJ/kg)

Energy Required -

Virgin (kJ/kg)

Annual Quantities

(million kg)Material

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Energy ConsumptionEnergy Consumption(Before and After Redesign)(Before and After Redesign)

Energy Consumption per Chair

0

0.2

0.4

0.6

0.8

1

1.2

Per Chair(low er bound)

Per Chair(upper bound)

En

erg

y (G

J)

Energy (original)

Energy (redesign)

Energy Consumption Annually

0

5

10

15

20

25

30

35

40

Annual (low erbound)

Annual (upperbound)

En

erg

y (m

illio

n G

J)

Energy (or iginal)

Energy (redesign)

Transportation Emissions Transportation Emissions ReductionsReductions

0.15590.18150.00060.000813.4625

Office chairs (upper bound, Gg)

0.13970.16270.00050.000712.0655

Office chairs (lower bound, Gg)

0.24610.28660.00090.001221.2522

Office chairs (pre-redesign, Gg)

0.49020.57080.00170.002542.3350g emission per kg shipped

3,3803,9361217291,900Total (Gg)

CONOxN2OCH4CO2

Overall, a 57-63% reduction in all emissions from original design!

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CONCLUSIONSCONCLUSIONS

�� Production energy savings = between 3.1 Production energy savings = between 3.1 and 15.4 million GJand 15.4 million GJ–– Equivalent to:Equivalent to:

�� a 5.9a 5.9--6.1 magnitude earthquake6.1 magnitude earthquake

�� 775,000 to 3.85M tons of TNT775,000 to 3.85M tons of TNT

�� power 310,000power 310,000--1.54M homes per year 1.54M homes per year

�� Transportation emission savings = Transportation emission savings = between 8 and 9 thousand metric tons of between 8 and 9 thousand metric tons of COCO22 annuallyannually–– However, annual US COHowever, annual US CO22 = 1,547 million = 1,547 million metric tonsmetric tons

CONCLUSIONSCONCLUSIONS

�� Significant opportunity for energy Significant opportunity for energy

and emissions reductions in office and emissions reductions in office

chair industrychair industry

�� Similar reductions could be achieved Similar reductions could be achieved

in other commonly used, mass in other commonly used, mass

produced productsproduced products

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Questions?Questions?