The information below is the summary of a paper I wrote for my government class. Please see the attached paper and sources for a more in depth explanation.

When comparing a bicycle and an electric bike making the average American commute of 30 miles per day (15 miles round trip) at a speed of 15 miles per hour the bicycle produces around 8.5 times more carbon emissions.





The bicycle

•  A cyclist can travel 30 miles in an hour using only 200 watt hours (Wright)
• 200 watt hours is only 174 calories, but humans are at best only 25% efficient at converting food calories to useable energy. 
• This means it would take at least 700 calories from food to travel 30 miles a day. 
• The average American Diet produces .005lbs of CO2 per calorie. (Martin) 
• 700 calories translates to 3.5lbs of CO2 a day and 1,278lbs a year.
  

The electric bicycle

• 500 watt hours is the high end end average for traveling at 15mph for 30 miles with one of the more popular electric conversion kits. This includes the loss of power from inefficiency in the electrical components.
  
• Inefficiencies and power losses in the grid and battery charger are 93.5% and 90% respectively. (Lemire-Elmore, Justin)
  
• This comes out to 585 watt hours produced at the power station per day.
• Per kilowatt hour coal produces .7lbs of CO2. ("Carbon Trust") 
• .585 kilowatt hours per day produces .41lbs of CO2 and a total of 149.5lbs a year.
  

Variables and counter-points

The environmental costs of producing and electric bike over a normal bicycle

    The environmental impact of production is almost meaningless when compared to life time operating cost. The extra components on an electric bike do add to the environmental impact, but not much:  "The li-ion battery plays a minor role regarding the environmental burdens of e-mobility irrespective of the impact assessment method used." (Notter 6550-6556)

The impact of diet

    This exercise assumes the average American diet. A vegetarian diet cuts the carbon footprint of the cyclists in half. (Pimental)

The use of carbon neutral energy sources

    Wind, solar, hydo, and nuclear make up 27.5% of Americas domestic energy production.

Cost in dollars

• 200 calories from white pasta costs $0.21 or $0.00105 per calorie. This comes out to $0.735 a day and $268.26 a year.
  
• At $0.13 per kilowatt hour the electric bike costs $0.076 a day and $27.76 a year.
  

"Resources - conversion factors ." Carbon Trust. Carbon Trust, n.d. Web. 6 Apr 2011. <http://www.carbontrust.co.uk/cut-carbon-reduce-costs/calculate/carbon-footprinting/pages/conversion-factors.aspx>.

Martin, Pamela. "Diet, Energy, and Global Warming." Earth Interactions. 10.9 (2006): 3. Print.

Notter, Dominic. "Contribution of Li-Ion Batteries to the Environmental Impact of Electric Vehicles." Environ. Sci. Technol.. 44.17 (2010): 6550–6556. Print.

Pimentel, David. "Sustainability of meat-based and plant-based diets and the environment." American Journal of Clinical Nutrition. 78.3 (2003): 660-663 . Print.

Wright, Chuck. "Bicycling Energy Calculator." Chuck Wright Consulting. Chuck Wright Consulting, n.d. Web. 5 Apr 2011. <http://chuck-wright.com/calculators/bicycle.html>.

Lemire-Elmore, Justin. "The Energy Cost of Electric and Human-Powered Bicycles ." Grin Tech. ebikes.ca, April 13, 2004. Web. 6 Apr 2011. <http://www.ebikes.ca/sustainability/Ebike_Energy.pdf>.