Well-to-wheel life cycle assessment of transportation fuels derived from different North American conventional crudes

Raw materials for buildings and construction account for more than 35% of global primary energy use and nearly 40% of energy-related CO2 emissions. The Intergovernmental Panel on Climate Change (IPCC) emphasized the drastic reduction in GHG emissions and thus, wood products with very low or negative carbon footprint materials can play an important role. In this study, a cradle-to-grave life cycle assessment (LCA) approach was followed to quantify the environmental impacts of laminated strand lumber (LSL). The inventory data represented North American LSL production in terms of input materials, including wood and resin, electricity and fuel use, and production facility emissions for the 2019 production year. The contribution of cradle-to-gate life cycle stages was substantial (>70%) towards the total (cradle-to-grave) environmental impacts of LSL. The cradle-to-gate LCA results per m³ LSL were estimated to be 275 kg CO2 eq global warming, 39.5 kg O3eq smog formation, 1.7 kg SO2 eq acidification, 0.2 kg N eq eutrophication, and 598 MJ fossil fuel depletion. Resin production as a part of resource extraction contributed 124 kg CO2 eq (45%). The most relevant unit processes in their decreasing contribution to their cradle-to-grave GW impacts were resource extraction, end-of-life (EoL), transportation (resources and product), and LSL manufacturing. Results of sensitivity analysis showed that the use of adhesive, consumption of electricity, and transport distance had the greatest influences on the LCA results. Considering the whole life cycle of the LSL, the final product stored 1,010 kg CO2 eq/m³ of LSL, roughly two times more greenhouse gas emissions over than what was released (493 kg CO2 eq/m³ of LSL) from cradle-to-grave. Overall, LSL has a negative GW impact and acts as a carbon sink if used in the construction sector. The study results are intended to be important for future studies, including waste disposal and recycling strategies to optimize environmental trade-offs.

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A Colorado-specific life cycle assessment model to support evaluation of low-carbon transportation fuels and policy

Environmental Research: Infrastructure and Sustainability ◽

10.1088/2634-4505/ac3f2a ◽

2021 ◽

Author(s):

Michael Somers ◽

Liaw Batan ◽

Baha Al-Alawi ◽

Thomas H. Bradley

Keyword(s):

Life Cycle Assessment ◽

Life Cycle ◽

Ghg Emissions ◽

Transportation System ◽

Assessment Model ◽

Carbon Intensity ◽

Low Carbon ◽

Transportation Fuels ◽

Transportation Sector ◽

Clean Fuels

Abstract The transportation sector accounts for over 20 percent of greenhouse gas (GHG) emissions in Colorado which without intervention will grow to over 30 million metric tons (MMT) of GHG emissions per year. This study seeks to develop a specific characterization of the Colorado fuel and transportation system using a customized life cycle assessment (LCA) model. The model (CO-GT) was developed as an analytical tool to define Colorado’s 2020 baseline life cycle GHG emissions for the transportation sector, and to examine Colorado-specific pathways for GHG reductions through fuel types and volumes changes that might be associated with a state clean fuel standard (CFS). By developing a life cycle assessment of transportation fuels that is specific to the state of Colorado’s geography, fleet makeup, policies, energy sector and more, these tools can evaluate various proposals for the transition towards a more sustainable state transportation system. The results of this study include a quantification of the Colorado-specific roles of clean fuels, electricity, extant policies, and fleet transition in projections of the state’s 2030 transportation sector GHG emissions. Relative to a 2020 baseline, electrification of the vehicle fleet is found to reduce state-wide lifecycle GHG emissions by 7.7 MMT CO2e by 2030, and a model CFS policy able to achieve similar reductions in the carbon intensity of clean fuels as was achieved by California in the first 10 years of its CFS policies is found to only reduce state-wide lifecycle GHG emissions by 0.2 MMT CO2e by 2030. These results illustrate the insensitivity of Colorado’s transportation fleet GHG emissions reductions to the presence of CFS policies, as proposed to date.

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