Various countries are undertaking initiatives to domestically produce battery-related critical materials. Within Finland, Keliber Technology Oy is developing capabilities for battery-grade lithium hydroxide monohydrate (LHM) production from spodumene ores. A detailed life-cycle assessment (LCA) of this pathway is conducted to determine its life-cycle GHG impacts using Argonne's R&D GREET (Research and Development Greenhouse gases, Regulated Emissions, and Energy use in Technologies) model. The analysis shows life-cycle GHG emissions of similar to 9.2 kg CO2-eq/kg LHM, dominated by contributions from three energy sources - diesel, natural gas, and electricity - and two material inputs - lime (CaO) and soda ash (Na2CO3). Sensitivity analyses highlight the potential to reduce these impacts using low-carbon electricity, sequestration of process CO2 emissions generated during CaO and Na2CO3 production, and bio-based energy for LHM production (by similar to 15 % each). A comparative analysis shows lower impacts for Keliber's LHM than for existing LHM production from Australian spodumene ores processed in China (by similar to 40 %).

This study quantifies and compares the life cycle greenhouse gas (GHG) emissions of renewable diesel (RD), sustainable aviation fuel (SAF), and biodiesel (BD) produced from two U.S. canola production systems: 1) emerging intermediate winter canola, typically grown in double- or relay-cropping systems between the growing seasons of main crops, and 2) main canola, mostly spring canola but also including winter canola, which are grown as primary crops occupying the field for a full growing season. Using the Research and Development version of the Greenhouse gases, Regulated Emissions, and Energy use in Technologies (R&D GREET) model and the most up-to-date life cycle inventory data-field trial data for intermediate winter canola (>37,000 acres) and recent national survey data for spring canola-this life cycle analysis (LCA) estimates the direct emissions from canola cultivation and harvest, the conversion of canola into fuels, fuel transportation, and combustion. In addition, we account for market-mediated emissions associated with a scenario of 0.5 billion gallons per year of spring canola-based biofuels, including induced land use change (ILUC), induced other crop (nonfeedstock) production changes, and induced livestock production changes. For intermediate winter canola, these market-mediated effects were not modeled, as ILUC is expected to be negligible due to its integration into existing rotations, and data are currently insufficient to reliably quantify other market-mediated changes. The estimated life cycle direct emissions of RD/SAF derived from intermediate winter canola and main spring canola are about 32 and 33 g of CO2-equivalent per megajoule of fuel (g CO(2)e/MJ), respectively. Corresponding emissions for BD from intermediate winter canola and main spring canola are about 30 and 31 g of CO(2)e/MJ, respectively. Farming is the dominant emissions source for both canola systems, with intermediate winter canola and main spring canola emitting about 19 and 20 g of CO(2)e/MJ, respectively. ILUC and other induced changes increase emissions of main spring canola-derived RD/SAF and BD by about 18 and 17 g of CO(2)e/MJ, respectively. These results indicate that the GHG emissions of biofuels produced from the two canola systems may differ substantially due to the different land use dynamics of the systems.

Most life-cycle assessments (LCAs) of alternative fuels evaluate electricity and hydrogen inputs using static or scenario-based carbon intensity assumptions. This study quantifies the impact of electricity and hydrogen on the life-cycle greenhouse gas (GHG) emissions of sustainable aviation fuels (SAFs). By coupling emission intensity projections for electricity grids and hydrogen production with Argonne National Laboratory’s R D GREET model, and following the life-cycle assessment (LCA) method of the International Civil Aviation Organization, we estimate life-cycle GHG emissions effects for two SAF pathways with comparatively high technology readiness levels: hydroprocessed esters and fatty acids (HEFA) from waste fats (tallow) and alcohol-to-jet (ATJ) from corn grain ethanol. Under the assumed trajectories for electricity grid decarbonization and hydrogen production carbon intensities, life-cycle GHG emissions of tallow HEFA and corn grain ATJ are estimated to be 7.7–12.5 gCO_2 e/MJfuel lower in 2035 and 9.6–13.7 gCO_2 e/MJfuel lower in 2050 relative to 2022 values. Additional facility-level mitigation measures, including carbon capture and waste heat utilization, could further reduce emissions per unit SAF. The work provides a prospective assessment by replacing static pathway intensities with a prospective LCA that couples SAF pathways to time-evolving electricity/hydrogen CIs and facility-level mitigation, quantifying dynamic GHG reductions to 2050. These findings underscore the importance of incorporating prospective energy system changes into SAF LCAs to more accurately capture future mitigation potential and inform effective aviation climate strategies.

The research and development version of the Greenhouse gases, Regulated Emissions, and Energy use in Technologies (R&D GREET (R)) model is publicly available and widely used for life cycle analysis (LCA) of energy systems and emerging technologies. However, its current Excel and .NET platforms face scaling and maintenance challenges. This paper introduces PyGREET, a modular Python-based platform designed for scalability and interoperability with other LCA tools. PyGREET's architecture separates domain modeling from numerical solvers, facilitating its maintenance and reusability for web-hosted and standalone derivative applications. Extensive validation across 2,119 technology pathways confirms computational equivalence with current platforms, yielding a negligible mean relative difference of 3.24 & times; 10- 8%. By establishing a robust, modular framework, PyGREET enhances transparency, user experience, and interoperability. This platform provides the foundation for reliable LCA modeling, and the continued expansion of R&D GREET at Argonne with advanced features for technology assessment and informed decision-making.

Steam methane reforming of natural gas is the primary method of producing hydrogen in the United States, accounting for 95% of all hydrogen produced there. Methane pyrolysis, an alternative production pathway that decomposes natural gas into solid carbon and hydrogen, both eliminates CO2 emissions associated with methane reforming and allows for additional income from carbon black. A life-cycle inventory of this process has been developed using ASPEN Plus to model the methane pyrolysis (plasma arc) process. From well to gate, hydrogen production via methane pyrolysis produces 2.78 kg CO(2)e/kg H-2 of greenhouse gas emissions using mass allocation of emissions between hydrogen and carbon black coproducts. The well-to-gate emissions are mainly driven by electricity consumption (similar to 38 kW h/kg H-2), which accounts for 81% of the emissions; if renewable electricity is used, well-to-gate emissions can be reduced to -0.448 kg CO(2)e/kg H-2.

Dedicated energy crops are promising feedstocks to make biofuels including jet fuels. This study applies life cycle analysis (LCA) to estimate direct well-to-wake (WTW) greenhouse gas (GHG) emissions (g CO2e/MJ) for jet fuel derived from five energy crops-biomass sorghum, miscanthus, switchgrass, poplar, and willow-via Fischer-Tropsch-to-Jet (FTJ) and Ethanol-to-Jet (ETJ) pathways. The WTW boundary includes direct emissions from biomass production, fuel production, and fuel combustion. The R&D GREET model is expanded to conduct the LCA, using national average biomass yields and farming inputs from the 2023 Billion-Ton Study. In addition, this study estimates emissions from market-mediated effects, including induced land-use change, induced other crop (non-feedstock) production changes, and induced livestock production changes using global economic and emissions factor models. On a per-dry U.S. ton basis, cultivation and harvest emissions are lowest for willow (51,565 g CO2e) and highest for biomass sorghum (104,488 g CO2e). Per-acre results show similarly high emissions for sorghum and lowest values for poplar and willow. Direct WTW emissions are substantially lower for FTJ (biomass sorghum: 5.5; miscanthus: 10.3; switchgrass: 11.7; poplar: 11.9; and willow: 8.7 g CO2e/MJ) than ETJ (33.2; 33.8; 34.8; 36.2; and 31.7 g CO2e/MJ, respectively). When market-mediated emissions are included, miscanthus exhibits the lowest total emissions across energy crop pathways. Although results are sensitive to modeling assumptions, they indicate that high-yielding perennial and woody crops, particularly when planted on marginal land, could significantly reduce WTW emissions for bio-jet fuels by combining low direct emissions with soil carbon gains and favorable market-mediated effects.

Hydrogen is increasingly recognized as a versatile energy carrier with the potential to reduce greenhouse gas (GHG) emissions across multiple sectors. This study investigates hydrogen production pathways in the Middle East and North Africa (MENA), with a focus on the Kingdom of Saudi Arabia (KSA). Given the region’s abundant natural gas resources, steam methane reforming (SMR) with carbon capture and storage (CCS) emerges as a prominent production route, while solar photovoltaic (PV)- and wind-based hydrogen offer renewable alternatives. A combined techno-economic assessment and life cycle GHG analysis is conducted for SMR with and without CCS and benchmarked against median values of PV- and wind-based hydrogen in KSA. The analysis evaluates the levelized cost of hydrogen (LCOH) and cradle-to-gate GHG emissions intensity (EI) across four pathways. SMR without CCS yields an LCOH of 0.44 USD/kgH2 and a EI of 9.1 kgCO2eq/kgH2, while SMR with CCS increases the cost to 1.54 USD/kgH2 but reduces EI to 4.1 kgCO2eq/kgH2. In comparison, renewable-based hydrogen exhibits considerably higher costs even excluding storage requirements needed to maintain a continuous supply similar to SMR, with PV-based production at 3.78 USD/kgH2 (EI: 2.3 kgCO2eq/kgH2) and wind-based production at 4.01 USD/kgH2 (EI: 0.92 kgCO2eq/kgH2). Sensitivity analysis indicates that the EI of SMR with CCS is strongly influenced by capture efficiency and upstream methane leakage. Overall, the findings indicate that SMR coupled with high-efficiency CCS, strict methane management, and renewable-powered electricity can achieve EIs comparable to those of renewable-based hydrogen, while maintaining a lower LCOH.

Natural gas (NG) plays a crucial role in current and future energy systems in the United States due to its abundance and affordability. In this study a life cycle analysis of the NG supply chain in the United States was conducted using Argonne's R&D GREET model, examining stages from recovery to distribution using reported field data processed and documented by National Energy Technology Laboratory. Supply chain emissions were evaluated across multiple spatial scales, including national average, overall regional production, region-to-region, and basin-to-region scenarios. The GHG intensity of the U.S. average NG supply chain was estimated at 10.3 kg CO2e/MMBtu (lower heating value), with a range across regions from 7.8 kg CO2e/MMBtu (Northeast) to 15.1 kg CO2e/MMBtu (Pacific). The analysis further assessed how upstream NG emissions influence the life cycle GHG emissions of key end-use applications, including electricity generation (0.044-0.086 kg CO2e/kWh from upstream NG in combined cycle facilities), hydrogen production (1.04-2.20 kg CO2e/kg H2 for steam methane reforming [SMR] and 1.06-2.23 kg CO2e/kg for autothermal reforming [ATR]), and transit bus operation utilizing compressed natural gas fuel (0.19-0.37 kg CO2e/mile) and hydrogen fuel (0.12-0.25 kg CO2e/mile for hydrogen produced in SMR and ATR).

This study evaluates ammonia as a potential marine fuel for a SUEZMAX tanker and compares it with methanol, liquefied natural gas, and conventional fuel oils. The motivation arises from the need to identify low-emission, cost-competitive fuel options that can reduce greenhouse gas emissions from international shipping. The central hypothesis is that ammonia produced from renewable energy sources can achieve lower well-to-wake greenhouse gas emissions with varying life cycle costs based on the region. Life cycle assessment and techno-economic analysis were performed for a thirty-year vessel lifetime on two representative trade routes: from Saudi Arabia to Japan and from Saudi Arabia to the Netherlands. Four ammonia production pathways were assessed: natural gas, natural gas with carbon capture, natural gas pyrolysis, and renewable electricity-based synthesis. Results show that wind-based ammonia produced in Saudi Arabia achieved the lowest life cycle well-to-wake greenhouse gas emissions, between 0.58 and 0.64 million metric tons, among all fuels when using regional grid process electricity. With renewable process electricity, ammonia produced from natural gas pyrolysis in Saudi Arabia showed comparable emissions of 0.37 to 0.44 million metric tons with wind-based ammonia of 0.37 to 0.43 million metric tons. Liquefied natural gas exhibited the lowest life cycle cost, between 402 and 412 million United States dollars, and the only negative carbon abatement cost, ranging from-277 to-322 United States dollars per metric ton of greenhouse gas, compared with high sulfur fuel oil. The findings indicate that renewable ammonia offers a promising long-term pathway for reducing shipping emissions, while liquefied natural gas remains the most costeffective option in the near term.

The electrification of the transport sector is crucial for reducing greenhouse gas emissions and the reliance on fossil fuels. Battery electric vehicles (BEVs) depend on critical materials (CMs) for their batteries and electronic components, yet their widespread adoption may face constraints due to the limited availability of CMs. This study assesses the implications of vehicle electrification and lightweighting (material substitution) on the U.S. CM demand for light-duty vehicles (LDVs) and medium- and heavy-duty vehicles (MHDVs). Market sales scenarios of 100% internal combustion engine vehicles (ICEVs), 100% BEVs, and a 50%/50% mix are considered. The findings reveal that LDVs dominate the total CM demand despite MHDVs requiring more CMs per vehicle. Cobalt, graphite, lithium, neodymium, and nickel are critical for the 100% BEV adoption scenario, whereas palladium and rhodium are critical for ICEVs. LDV lightweighting increases total CM quantity per vehicle due to steel replacement with aluminum but reduces the vehicle's mass, operational energy consumption, and reliance on high-concern battery-related CMs. Transitioning from nickel manganese cobalt (NMC622) to lithium iron phosphate (LFP) battery chemistry reduces CM use but increases demand for strategic materials such as copper and phosphorus. This study uniquely evaluates U.S. CM demand for LDVs and MHDVs across conventional and electric powertrains and investigates light-weighting and battery chemistry impacts.

Waste-to-Renewable Natural Gas (RNG) offers a promising solution to alleviating waste management challenges by converting waste into renewable fuels. This process can significantly reduce greenhouse gas (GHG) emissions, as demonstrated through a comprehensive life cycle analysis. Biogas upgrading is essential to enhance the methane concentration, though it could be energy-intensive and susceptible to methane slippage. Four commonly adopted biogas upgrading technologies, including pressure swing adsorption, membrane separation, chemical absorption, and water scrubbing, are considered. Our study evaluates the life cycle GHG emissions of RNG production from major sources of waste in the U.S. including wastewater sludge, food waste, landfill gas, dairy cow manure, and swine manure. Meta-analysis was conducted to assess methane slippage and energy consumption of biogas upgrading and associated GHG emissions, while accounting for potential avoided emissions from conventional waste management, which vary widely (ranging from -481.0 to 101.8 g CO2-eq/MJ). Under default upstream assumptions, representative carbon intensity of RNG varies from about -125 g of CO2-eq/MJ (dairy cow manure) to about 41 g of CO2-eq/MJ (wastewater sludge). We also explored RNG applications in producing hydrogen, ammonia, and compressed/liquefied forms. These findings highlight the potential of RNG and RNG-derived fuels to reduce GHG emissions and bolster the U.S. energy supply.

Renewable hydrogen is receiving increasing attention for its potential as a flexible energy carrier in sectors such as transportation and industry. Specific cost and carbon intensity (CI) of renewable hydrogen production vary largely based on the location, owing to differences in renewable energy resources, as well as the supply chain dynamics. This study maps the techno-economic and life cycle greenhouse gas emissions of renewable hydrogen production in the Middle East and North Africa region, leveraging abundant solar and wind resources. The work investigates the variability in hydrogen costs and CI, optimally sizing proton-exchange membrane (PEM) electrolyzers to account for partial and cyclic loading, and explores standalone versus grid-connected systems. PEM capacity ratios of 52 %-63 % for photovoltaic (PV) systems and 28 %-82 % for wind systems were identified as optimal, with hydrogen production costs ranging from $3.8-$4.8/kg for PV and $2.0-$7.0/kg for wind. CIs span from 1.9 to 3.7 kg CO2,eq/kg H2 for PV and 0.4-7.7 kg CO2,eq/kg H2 for wind systems. The study highlights significant cost and CI reductions achievable with technological advancements and co-product revenue from oxygen and excess electricity sales.