Browsing by Subject "Decarbonization"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Assessing the Prospects for Minnesota-Produced Sustainable Aviation Fuel
    (2025-05-01) Anderson, Casidy; Anderson, Meghan; Lackens, Sophia
    The aviation sector contributes about 4% of global greenhouse gas (GHG) emissions (Ritchie, 2024). Sustainable Aviation Fuel (SAF) remains the only viable option for meaningful decarbonization in the near term. Minnesota is uniquely positioned to produce SAF in-state because of its existing partnership with Delta Airlines through the Minnesota SAF Hub, its thriving agricultural industry, and its proven interest in investing in decarbonization. There are four relevant pathways to produce SAF in Minnesota: Hydroprocessed Esters and Fatty Acids (HEFA), Alcohol-to-Jet (AtJ), Gasification with Fischer-Tropsch Synthetic Paraffinic Kerosene (FT), and Power to Liquid (PtL). The agricultural pathways, HEFA, AtJ, and FT, are the most technologically mature. The carbon intensity score for each pathway varies heavily by the feedstock. Soy, winter oilseeds, fats, oils, and greases (FOG), corn, forestry residue, and agricultural residues are the primary feedstocks considered for Minnesota-made SAF. Additionally, each pathway will require hydrogen, water, and land use. Energy and infrastructure considerations remain a challenge to production and will require greater investment to create the fundamental resources necessary for producing SAF in the state. Funding also remains a barrier, as SAF currently costs 2 to 10 times more than traditional jet fuel and is not expected to reach price parity at scale. Policy change, especially related to permitting processes and tax incentives, will be necessary to support SAF production in the short and long term. This report identifies seven areas for recommendation: research and development, pathway prioritization, foundational investment, funding barriers assessments, water concerns, and sustainable economy promotion.
  • Thumbnail Image
    Item
    Dedicated transit lanes help attract riders, reduce carbon emissions
    (Center for Transportation Studies, University of Minnesota, 2024-06) Center for Transportation Studies
    This research brief summarizes report CTS 23-09, The Value of Dedicated Right of Way (ROW) to Transit Ridership and Carbon Emissions, that examined the influence of four types of ROW on transit ridership and emissions.
  • Thumbnail Image
    Item
    The Value of Dedicated Right of Way (ROW) to Transit Ridership and Carbon Emissions
    (Center for Transportation Studies, University of Minnesota, 2023-12) Cao, Jason; Tao, Tao; Johnson, Isak; Huang, Hannah
    Transit agencies have adopted various types of right of way (ROW) for transit routes, including mixed traffic, semi-exclusive ROW, exclusive ROW, and grade separation, but few empirical studies have quantified their impacts on ridership and carbon emissions. Using data collected from transit agencies in the US, this research aimed to examine the impacts of dedicated ROW. We applied the gradient boosting decision tree method to estimate the nonlinear relationships between yearly route-level transit ridership and five types of independent variables, with a focus on ROW. The results showed that ROW contributes 18% of the power to predicting transit ridership, which is the largest among all the independent variables. Upgrading from mixed traffic to semi-exclusive ROW could boost ridership by 70,000, on average. A further upgrade to an exclusive ROW could add 3.68 million passengers. Moreover, the number of stops, transit route commence year, population density, signal priority, number of park-and-ride facilities, headway, network density, and route length all have non-trivial contributions to predicting ridership. Upgrading the operating environment could substantially reduce carbon emissions, up to 6.37 million pounds of CO2e. Overall, elevating ROW levels could notably enhance transit ridership and reduce carbon emissions, locating transit routes in the areas with adequate population density and network density could improve their performance, deploying signal priority and improving transit frequency also help, and increasing the share of electric buses could further decrease carbon emissions.