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ENGS 171 Industrial Ecology Redesigning the Bicycle. Alan Salas, Kevin Dahms , Jess Zarker , Jose Ordonez, Robbie Moss. Recap from last time. Part 2: Redesign. Design Requirements. Seat Mast Tube. FUNCTION: To support the weight of the person. Acts as a column in compression
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ENGS 171Industrial EcologyRedesigning the Bicycle Alan Salas, Kevin Dahms, Jess Zarker, Jose Ordonez, Robbie Moss
Design Requirements Seat Mast Tube FUNCTION: To support the weight of the person. Acts as a column in compression OBJECTIVES: Ideally, minimize environmental impact and mass CONSTRAINTS: Recyclable High strength and stiffness FREE VARIABLES: Material choice, shape, color
Indices For minimizing environmental impact (embodied energy and CO2) Minimizing Embodied Energy Minimize Hmρ/ E1/2for stiffness Minimize Hmρ/ σyfor strength Minimizing CO2 Minimize CO2ρ/ E1/2 for stiffness Minimize CO2ρ/ σy for strength
Material Selection Analysis for seat mast tube (modeled as a column)
Material Selection Lower embodied energy! Low-alloy steel Bamboo!
Material Selection Low-alloy steel Lower CO2 Bamboo!
Material Selection Low-alloy steel Bamboo! Lower density
Mass vs. Cost Cheaper Low-alloy steel Bamboo, Softwood and Hardwood
Mass vs. Embodied Energy Less embodied energy Low-alloy steel Bamboo, Softwood and Hardwood
Cost vs. CO2 Less CO2 Low-alloy steel Bamboo, Softwood and Hardwood
Cost vs. Embodied Energy Less embodied energy Low-alloy steel Bamboo, Softwood and Hardwood
Shape 4.5 mm 29 mm 38 mm
Shape • These specifications are for Iron bamboo, which is the strongest type • If it is a more flexible bamboo, use wider and thicker tubing • If internal diameter is less than 29 mm, there will be a hoop stress, which we didn’t look into carefully in this analysis. • http://www.useful-arts.com/sua/instructions/bamboobikekit/harvest/
Use Phase Analysis • Negligible environmental impact • NEXT Bike • Maintenance: paint, wheels, lost accessories, oil • Once child grows, bike becomes obsolete
Use Phase Analysis (cont.) • BamBIKE: • Introduce a service program • Convert the product into a service • Incentive: offer free repairs (only cost is purchasing the parts), offer discounts, etc. • Return old bike, obtain new larger bike at a discount “If your child grows faster than bamboo, we have a solution for you!”
Eco-Audit of redesigned bike 34% reduction
CO2 of Entire process 40% reduction
Specifically looking at components 75% reduction 87%
CO2 of materials 74% reduction 87%
Water-audit of redesigned bike Why isn’t there a significant change???
Economic Analysis • Materials: • Low alloy steel • 0.89-0.93 USD/kg • At 3.68 kg, price is $3.35 • Bamboo • 1.37-2.05 USD/kg • At 0.4 kg, price is $0.82 • BUT, labor is a problem: • More labor intensive to assemble BamBIKE, so higher costs are associated • This is why it is currently only offered to very specialized, high end consumers
Economic Analysis • CNN article published today about a bamboo bike company located in Zambia: “Each frame takes between 40 and 60 man hours to make[…]Every piece of bamboo is having different colors, different bend, so every frame is unique." • That explains the high costs, and why these “high-end, lightweight bicycles” have “a price tag of around $900” and are “primarily aimed at the international market”. http://edition.cnn.com/2012/05/31/business/bamboo-bicycles-zambia-zambikes/index.html?hpt=hp_c4
Aesthetics are a major feature refractive quality of paint, extra features (painted plastic), logo designs Considering Aesthetics: Paint and Plastics • Aesthetics are also subjective; malleable • Don’t outweigh the environmental impacts: • Greenhouse gas emissions: VOCs, CO2, NOx, SOx , and PM • Health Concerns for workers • “Eco-Design” Water-based paint Water-based non-toxic wood varnish logo
Conclusions and Recommendations Findings • Bamboo is an appropriate substitute for steel • Saving 91 MJ per bike means saving energy of 245 bananas per unit!!! Considerations • Industrial infrastructure is currently nonexistent • This is the foundation for a sustainable lifestyle
Conclusions and Recommendations There are other important benefits of bamboo that could be further exploited: “One of nature's fastest growing resources” “Has great shock absorbing abilities that contribute to a smooth and eco-friendly ride” http://edition.cnn.com/2012/05/31/business/bamboo-bicycles-zambia-zambikes/index.html?hpt=hp_c4
Moving forward… Hemp Wood Wood and ideally… DIAMOND!