During spring quarter, Kyra Lemmelin (BSCE ’22) created a comprehensive greenhouse gas emissions calculator for the Tasar World Championships (TWC), a sailing competition that will take place in Seattle in September 2022. The calculator determines the equivalent metric tons of carbon dioxide emissions (MTCO2-e) emissions and accounts for the travel of the contestants and judges, fuel used by the boats and the large group meals held throughout the event. In the future, the calculator can be customized and used for TWCs or other international regattas.
Carbon emissions are categorized into three scopes for greenhouse gas emissions accounting:
The TWC carbon emissions calculator includes approximate estimates for Scope 1 emissions that are produced during the boat races. The boats used in the races are not motorized, but the ones used for event safety, by the judging committee, and for setting the up the course area. After determining the type of boat and estimating fuel consumption for the entire 12-day event, it was estimated that 2.6 MTCO2-e of emissions would be produced assuming an emission factor of 2.3 kg of CO2 per L of gasoline1, or 2.7 kg of CO2 per L of diesel2.
Because the 2022 TWC will be held in Seattle, the calculator does not include Scope 2 emissions since Seattle Public Utilities is a carbon neutral utility. Most of the carbon emissions for the event will result from international plane travel or Scope 3 emissions. For air travel, there are many existing carbon calculators, but none included all of the factors that can affect the carbon emissions for a given flight. These factors include the model of the plane, the number of seats, the length of the flight, and the seating class2. Additionally, there is no direct relationship between distance travelled and carbon emissions because taxi, takeoff, and landing contribute significantly to the total fuel burn3. The calculator uses an emission factor of 3.15 g of CO2 per gram of jet fuel used4. Additionally, because first and business class seats are less dense than economy, the calculator follows the industry standard4 and doubles the emissions factor for passengers in these sections.
For the TWC, it was also assumed that participants who used air travel would fly through the same airports for their roundtrips. For ground transportation to the event, it was assumed that every participant rode separately in a typical passenger vehicle that uses 9.3 L of gas per 100 km5 and produces 2.3 kg of CO2-e for every 1 L of gas burned6. A safety factor of 1.1 was applied to all emissions travel-related Scope 3 emissions to account for underestimates.
The remaining Scope 3 emissions were from event meals and participant gifts. Using an emissions factor of 1.7 kg of CO26 for meals, approximately 1.9 Mt of CO2 (which includes safety factor of 1.5) would be produced for five group events with approximately 155 people. The only other major product that was purchased for the event was a custom-made cotton T-shirt for the 155 participants. With an emission factor of 3.3 kg of CO2 per T-shirt7 and assuming a safety factor of 1.5, there would be about 0.7 Mt of CO2 produced.
This project will help the TWC organizers to establish their baseline carbon footprint, and the calculator can be modified to estimate emissions for future events. Organizers plan to purchase high quality carbon offsets to account for unavoidable emissions and will continue their efforts to reduce emissions as they continue to strive for sustainable events. If you would like a copy of the calculator, please email Dr. Phillip Thompson.
Works Cited