Redesigning the Office Chair Part 2

Transcription

1 Redesigning the Office Chair Part 2 ENGS 171 May 27, 2004 by Brian Henthorn and Charles Pahl PREVIOUS ENVIRONMENTAL ASSESSMENT 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. < 1

2 Material Steel Aluminum Zinc PREVIOUS ENVIRONMENTAL ASSESSMENT Our Office Chair (kg) Required - Virgin (kj/kg) 40, , , Required - Recycled (kj/kg) 18, , , Chair (Virgin) (kj) 166, , , Chair (Recycled) (kj) 75, , , Plastics (polyurethane) , , , , Fabrics (Olefin, PP) , , , , Hydraulic Oil , , , Total ,004, , Replace table with newer one PREVIOUS ENVIRONMENTAL ASSESSMENT Material Annual Quantities (million kg) Required - Virgin (kj/kg) Required - Recycled (kj/kg) Total (Virgin) (kj) Total (Recycled) (kj) Steel , , ,101, ,760, Aluminum , , ,529, ,686, Zinc , , , , Plastics (polyurethane) Fabrics (Olefin, PP) , , , , ,533, , ,897, , Hydraulic Oil , , , Total ,875,354 12,254, Replace table with newer one 2

3 Hierarchy Making Materials Transport Assembly Disassembly Annual Values range between GJ Total to produce one chair ranges: ~ MJ (recycled or not) Calculated assembly: 14,500kJ Agreeing with hierarchy of energy 3

4 TRANSPORTATION COSTS Plays a significant part to environmental impacts TRANSPORTATION COSTS By the American Trucking Institute Shipment Characteristics by Mode of Transportation, US (percent of total tonnage) 69.1% Truck Rail Water Air Pipeline 4

5 Truck

6 TRANSPORTATION COSTS 7.6 Billion Tons = 6,895Tg Lower Bound: 13.68kg/chair * 36.7Mchairs = 502Gg Upper Bound: 22.75kg/chair * 36.7Mchairs = 835Gg US Truck Shipment: % 0.012% Transportation Pollution CO 2 CH 4 N 2 O NO x CO NMVOC Total (Gg) 291, ,936 3, g emission per kg shipped Office chairs (lower bound, Gg) Office chairs (upper bound, Gg)

7 Transportation Pollution Percentage of Estimated Total NOx emissions (Gg) (Using the Upper Bounds) Difficult to compare energy to emissions Production Assembly Transportation Study of Power plant guidelines set NOx emissions at ng/J Pie chart compares using this conversion between energy & pollutant Deep REDESIGN PROCESS ALTERNATIVES Air hockey table floor - no need for wheels TYPE Product change Moderate/Deep Integrating chair into desk - no separate chair unit No need for height adjustments - several chairs w/ different heights Benches/couches Product change Product change Product change Localized production/sale Transport reduction 7

8 Moderate REDESIGN PROCESS Service-lease chairs or components Alternative height adjustment (pin/notch, springs, screw) Detachable fabric - wears out quickest Replace foam with air Design for reuse Design for disassembly Design for disassembly/extend product lifetime Dematerialization Fleets use alternative fuels Transport reduction Redesign wheel-system Dematerialization REDESIGN PROCESS Shallow/Moderate Reducing materials (cardboard) by stamping info on plastic Molded butt and back together Labeling each type of material Shallow Dematerialization Dematerialization Design for recycling Using a uniform plastic/nylon for entire chair Environmental friendly fabric Replaceable wheels Plastic clips instead of staples and screws Plastics identification Honey comb plastic Design for Recycling Design for Recycling Design for Disassembly Design for Disassembly Design for Recycling Dematerialization 8

9 REDESIGN PROCESS Deep Solutions are infeasible & need societal change Lease possible with companies Redesign wheels Alternatively-fueled fleets ALTERNATIVES Selected Alternatives Using a uniform plastic/nylon for entire chair Reducing materials (cardboard) by stamping info on plastic Nylon screws for fasteners instead of steel screws Alternative height adjustment - nylon screw SCOPE shallow shallow/moderate shallow moderate TYPE Design for recycling Dematerialization Design for disassembly Design for disassembly Plastics identification Labeling each type of material Detachable fabric - wears out quickest shallow shallow/moderate moderate Design for recycling Design for recycling Design for disassembly/extend product lifetime Replace foam with air moderate Dematerialization Molded butt and back together shallow/moderate Dematerialization Maybe insert highlight above for what investigated 9

10 Implementation Eliminating Cardboard Paneling Though already use 100% recycled, can stamp information into plastic instead Height Adjustment Redesign Seat Height Pin-Notch System Requires difficult removal of load- bearing pin Springs Height controlled by user weight Screw 10

11 Seat Height Implementation Screw Have the support rod be a large screw that winds into the base for height adjustment Air Cushioning Uses air as a substitute for foam Encasing plastic is Poly-Vinyl Chloride (PVC) Fabric Cover Air Cushion Plastic Frame -Create different pockets for ergonomics 11

12 Molded Seat and Back Eliminates need for steel connecting bar Alternative Fasteners Replace metal screws inlaid into plastic frame with nylon screws into nylon frame Allows for easier recyclability and disassembly Replace staples connecting fabric and plastic frame with elastic band on edge of fabric Allows for easy detachment of fabric backing for recycling/disposal/replacement 12

13 Design for Recycling Use uniform plastics throughout chair (Nylon or alternative) Label plastics with corresponding number to aid recycling Label composition of all materials may have proprietary issues Recalculated Material Composition Material Original Office Chair (kg) Densities (g/cc) Volume (cc) Redesigned Office Chair (kg) Steel Aluminum Zinc Plastics (polyurethane) Other Total

14 Recalculated Production (per chair) Material Plastics lower bound (polyurethane) Plastics upper bound (polyurethane) Fabrics (Olefin, PP) Total (lower bound) Total (upper bound) Redesigned Office Chair (kg) Required - Virgin (kj/kg) 72,100 72,100 74,300 Required - Recycled (kj/kg) 44,600 44,600 42,300 Chair (Virgin) (kj) 377, ,709 15, , ,793 Chair (Recycled) (kj) 233, ,556 8, , ,143.5 Recalculated Production (Annually) Material Plastics lower bound (polyurethane) Plastics upper bound (polyurethane) Fabrics (Olefin, PP) Total (lower bound) Total (upper bound) Annual Quantities (million kg) Required - Virgin (kj/kg) 72,100 72,100 74,300 Required - Recycled (kj/kg) 44,600 44,600 42,300 Total (Virgin) (GJ) 13,865, ,798, , ,418, ,351,690.8 Total (Recycled) (GJ) 8,576, ,865, , ,892, ,180,

15 Consumption (Before and After Redesign) Consumption per Chair Consumption Annually E n e r g y ( G J ) Per Chair (low er bound) Per Chair (upper bound) (original) (redesign) E n e r g y ( m i l l i o n G J ) Annual (low er bound) Annual (upper bound) (original) (redesign) Transportation Emissions Reductions Total (Gg) g emission per kg shipped Office chairs (pre-redesign, Gg) Office chairs (lower bound, Gg) Office chairs (upper bound, Gg) CO 2 291, CH N 2 O NO x 3, CO 3, Overall, a 57-63% reduction in all emissions from original design! 15

16 CONCLUSIONS Production energy savings = between 3.1 and 15.4 million GJ Equivalent to: a magnitude earthquake 775,000 to 3.85M tons of TNT power 310, M 1.54M homes per year Transportation emission savings = between 8 and 9 thousand metric tons of CO 2 annually However, annual US CO 2 = 1,547 million metric tons CONCLUSIONS Significant opportunity for energy and emissions reductions in office chair industry Similar reductions could be achieved in other commonly used, mass produced products 16

17 Questions? 17