Bicycle rider in Portland, Oregon.
Technical Summary

Bicycle Infrastructure

Project Drawdown defines bicycle infrastructure as the increased installation of bicycle paths to encourage more bicycle usage in urban environments. This solution replaces the use of motorized road vehicle infrastructure (i.e., more lanes for cars and buses).

In 2018, just under 3 percent of urban mobility around the world was completed by bicycle, with some places, like the Netherlands, having over 30 percent of trips done by bike[1]. In the EU, where more than 7 percent of urban trips are completed by bicycle, the net economic benefits of bicycle infrastructure improvements have been estimated to be as high as €513 billion annually[2]. This accounts for reduced costs associated with health expenditures, congestion, fuel consumption, air pollution, and more. Research has shown that bicycle infrastructure has a significant effect on the mode of travel chosen in urban environments, most notably through the provision of separate cycling facilities along heavily traveled roads and intersections and through traffic calming in residential neighborhoods.

This analysis investigates the greenhouse gas and direct financial impacts of an increase in urban bicycle ridership through expanded implementation of bicycle infrastructure.

Methodology

Total Addressable Market

The total addressable market for bicycle infrastructure is defined as the total projected passenger-kilometers traveled in urban environments from 2020 to 2050. Implementation was assumed to be in kilometers of lanes (bicycle or car/bus/other) installed, and we assumed a fixed usage of each lane-kilometer installed, with one bicycle lane-kilometer generating 5.2 million bicycle passenger-kilometers annually.

Adoption Scenarios

Data on existing global bicycle adoption in the literature are limited. To determine the 2018 global adoption of 898 billion passenger-kilometers, data were used from a 2015 collaborative study on cycling by the Institute for Transport and Development Policy (ITDP) and University of California-Davis (UCD), which included projections[3].

Impacts of increased adoption of bicycle infrastructure from 2020 to 2050 were generated based on two growth scenarios. These were assessed in comparison with a Reference Scenario, in which the solution’s market share was fixed at current levels.

  • Scenario 1: This case is aligned with the projected data from the global ITDP/UCD study, reflecting a reasonable high-adoption pathway.
  • Scenario 2: Here the projections from sources for each Project Drawdown region were used and expanded upon with assumptions of 30 percent growth per 10-year period. This scenario was based on a total of 31 adoption estimates from eight sources. Estimates were calculated for each region, summed to determine a global value, and interpolated back to the estimated current adoption.[4]

Emissions Model

Emissions were calculated based on fuel use, but as we considered some electric modes in the two scenarios (electric cars and buses), and we also included some electricity emissions. Data for this came from the U.S. Office of Energy Efficiency and Renewable Energy, the ITDP, and the Intergovernmental Panel on Climate Change (IPCC) for emissions factors.

Financial Model

The first costs of bicycle infrastructure adoption were estimated from 29 different lane installation cost  data points, collected from 17 sources. Operating costs were taken as the maintenance costs for road and bicycle lanes. They were much lower for bicycle lanes because the wear and tear from bicycles is lower than that from cars and buses.

Integration

Bicycle infrastructure is considered a high-priority Project Drawdown solution, so its adoption was not limited in the integration process.

Results

Should global ridership increase to 3.4 trillion passenger-kilometers, or 490,000 additional kilometers of bicycle lanes over that in 2018, by 2050 (as assumed in Scenario 1), municipalities would avoid emissions of more than 2.56 billion tons of carbon dioxide-equivalent, while providing construction savings of US$2.7 trillion and lifetime operating saving of US$827 billion. [5],[6] These financial savings compare the cost of constructing new roads and lanes for increased light-duty vehicle traffic with the cost of remodeling or renovating roads to accommodate and encourage bicycle ridership. In Scenario 2, almost 1 million additional lane-kilometers installed (i.e., to 6 trillion passenger-kilometers of ridership) would result in 6.6 gigatons of carbon dioxide-equivalent emissions avoided.

Discussion

The ITDP/UCD study found that combined cycling (regular and e-bicycles) could save US$24 trillion between 2015 and 2050 and avoid 225 million metric tons of carbon dioxide-equivalent emissions in 2050. The total bicycle and e-bicycle impact in Scenario 1 is 172 million metric tons of emissions reductions in 2050, with total construction savings of US$3 trillion from 2020 to 2050. These results are much more conservative, in part because we do not include car fuel, vehicle purchase and maintenance cost savings, and some other knock-on savings for the bicycle infrastructure solution.[7] Total bicycle and e-bicycle impact in Scenario 2 is higher, at 493 million metric tons of emissions reductions in 2050, suggesting that the ITDP/UCD adoption probably lies between our Plausible and Scenario 2s.

Additional benefits of cycling include improved health and lower health care expenses[8] and an increase in the uptake of public transport by making more public transport stops accessible by bicycle. These benefits are of great value, and are not included in our analysis. Many factors affect the expansion of bicycle infrastructure and the rates of adoption: besides the obvious ones, such as weather, type of bike lane, and geography of the city, other attributes of the city and its residents play important roles. All of these attributes are beyond the scope of this report. Nevertheless, our analysis shows that the benefits we can measure are large when there is significant expansion in bike infrastructure.


[1] Thomas Blondiau, Bruno van Zeebroeck, & Holger Haubold. (2016). Economic benefits of increased cycling. In Transportation Research Procedia 14 (Vol. 14, pp. 2306–2313). Elsevier B.V. https://doi.org/10.1016/j.trpro.2016.05.247

[2] From Neun, M., & Haubold, H. (2016). The EU Cycling Economy: Arguments for an integrated EU cycling policy (pp. 1–16). Brussels, Belgium: European Cyclists’ Federation. Retrieved from www.ecf.com

[3] Mason, Jacob, Fulton, Lew, & McDonald, Zane. (2015). A Global High Shift Cycling Scenario. Institute for Transportation and Development Policy and the University of California, Davis. Retrieved from https://www.itdp.org/wp-content/uploads/2015/11/A-Global-High-Shift-Cycling-Scenario_Nov-2015.pdf

[4] “Current” adoption is defined as the amount of functional demand supplied by the solution in 2018. This study uses 2014 as the base year.

[5] The net operating savings for the full lifetime of all units installed during the period 2020–2050.

[6] Unless otherwise noted, all monetary values are presented in 2014 US$.

[7] We only include costs that would be attributable to municipalities rather than the whole society—such as health costs, which are challenging to estimate at the global level.

[8] This is so even after accounting for the increased risk of injury from collisions and accidents.