SUV Tire Deflation

Action by: Tyre Extinguishers

Carbon Offset: 1.112 Metric Tons

Vintage: 2022

Location: Worldwide

Tyre Extinguishers are an anonymous, leaderless group that aims to "make it impossible to own a huge polluting 4x4 in the world’s urban areas." To accomplish this goal they encourage individuals to deflate the tires of SUVs by inserting lentils and other small hard objects into tire valves, thereby inconveniencing vehicle owners and temporarily preventing vehicles from being driven. Between March and November of 2022 they estimate that over 10,000 SUVs were deflated.

$$Total_{SUVS} \times {AverageCarCO_2peryr \times SUV_{multiplier} \over 365}$$

Methodology

A typical passenger vehicle emits 4.6 metric tons of carbon per year.1 A typical Sports Utility Vehicle (SUV) emits approximately 13% more than an average passenger vehicle.2

We assume that an SUV with deflated tires is undrivable for approximately 1 day.

Tyre Extinguishers estimate that over 10,000 SUVs were rendered temporarily inoperable over a 6 month period (we cap this at 10,000).3

The amount of CO2 temporarily stored by disabling 10,000 SUVs for 1 day is therefore:

$$ \begin{aligned} tCO_2 &= TotalSUVS \times {AverageCarCO_2 \times SUV_{multiplier} \over 365} \\[5pt] &= 10{,}000 \times {4.6 \times 1.13 \over 365} \\[5pt] &= 142.42 \end{aligned} $$

We then use an equivalence factor of 128. This is calculated using the Lashof method with a discount rate of 0 and a time horizon of 100 years.45 This equivalence factor posits that the effects of the release of 1 tonne of CO2 emissions is offset by the storage of 128 tonnes of CO2 for 100 years.

$$ \begin{aligned} Offset &= {tonne_{years}CO_2 \over equivalence} \\[5pt] &= {142.42 \over 128} \\[5pt] &= 1.11265625 \end{aligned} $$

  1. https://www.epa.gov/greenvehicles/greenhouse-gas-emissions-typical-passenger-vehicle ↩

  2. https://www.ntc.gov.au/sites/default/files/assets/files/Carbon-dioxide-emissions-intensity-for-new-Australian-light-vehicles-2019.pdf ↩

  3. https://www.tyreextinguishers.com/news?slug=tyre-extinguishers-hit-target-of-10000-suvs-disarmed-worldwide ↩

  4. Chay et. al. calculate this equivalence factor using Lashof. Chay et. al. (2022) Unpacking ton-year accounting. Carbon(plan). Online: https://carbonplan.org/research/ton-year-explainer ↩

  5. Fearnside et. al. (2000) Accounting for time in mitigating global warming through land-use change and forestry. Mitigation and adaptation strategies for global change. ↩