Category: Multi-Slide Guides

The Digest’s 2025 Multi-Slide Guide to Heavy-Duty H2 Combustion

July 27, 2025 | Jim Lane

Sandia National Laboratories is advancing hydrogen internal combustion engines (H2ICE) for hard-to-electrify sectors, targeting 2024-2027 market entry. Key findings: increased swirl improves H2 mixing, yet cyclic variability remains. Crucially, hydrogen significantly delays hydrocarbon auto-ignition, providing new insights into oil pre-ignition. Pre-chamber fueling with H2 reduces cyclic variability and enables ultra-lean operation, outperforming natural gas. This […]

The Digest’s 2025 Multi-Slide Guide to Alcohol Combustion in CI Engines

July 24, 2025 | Jim Lane

This presentation highlights ethanol/methanol for off-road decarbonization, despite their low ignitability for compression ignition. Pilot injections are key, creating a flame kernel to ignite main sprays. Ethers improve ignitability but reduce efficiency in single-fuel blends, lowering NOx. Methanol port injection struggles with vaporization, causing liquid entry and weak combustion. Notably, active pre-chamber jets achieve diesel-like […]

The Digest’s 2025 Multi-Slide Guide to DNS/LES and Modeling of SAF Flame Stabilization

July 23, 2025 | Jim Lane

High-fidelity simulations are crucial for Sustainable Aviation Fuel (SAF) combustion modeling. DNS of aero-combustors shows premixed flames dominate heat release, with edge flames re-igniting extinction regions via coupled deflagration and ignition. Crucially, edge flames cause turbulent kinetic energy back-scatter, missed by current LES models. New constrained Deep Neural Network models significantly improve multi-modal combustion predictions. […]

The Digest’s 2025 Multi-Slide Guide to Mixing-Controlled Compression-Ignition Combustion with Low-Lifecycle-CO2 Fuels

July 22, 2025 | Jim Lane

This project de-risks Ducted Fuel Injection (DFI) for heavy-duty engine decarbonization with Low-Lifecycle-CO2 Fuels (LLCFs). The first-ever DFI retrofit for a production multi-cylinder engine was successfully implemented. Initial DFI testing revealed substantial NOx reductions (up to 80%) but significant soot increases (up to 1370%), indicating the need for further optimization. A robust mechanical alignment technique […]

The Digest’s 2025 Multi-Slide Guide to Alcohol Spray and Hydrogen Jet Experiments and Modeling

July 21, 2025 | Jim Lane

This project supports off-road engine decarbonization via methanol and hydrogen, emphasizing injection challenges. Methanol experiments reveal significant plume collapse and accelerated inter-plume regions under flash-boiling, with slow evaporation causing potential wall wetting. Hydrogen jet studies show complex shockwave structures and substantial local cooling. These findings highlight key difficulties for CFD modeling and injector optimization. The […]

The Digest’s 2025 Multi-Slide Guide to SAF

July 20, 2025 | Jim Lane

Global planned capacity for Renewable Diesel (RD), Sustainable Aviation Fuel (SAF), and Dimethyl Ether (DME) reached 23.699 billion units by June 2024, a 3% increase. Key drivers include RFS RVOs and Net Zero targets. A significant development is California’s withdrawal of its Advanced Clean Fleets (ACF) waiver request, creating uncertainty for fleet electrification. Feedstock affordability […]

The Digest’s 2025 Multi-Slide Guide to Feedstocks and Advanced Agriculture

July 17, 2025 | Jim Lane

Demand for Sustainable, Affordable, Reliable, Available (SARA) feedstock is sky-high, especially for SAF, but it’s tough to find. Competition and pushback exist for conventional crops, necessitating more residues, like forest waste. Positively, new technologies for waste-to-fuels and intermediate crops are arriving, with new crops becoming available and marginal lands being utilized. The 2023 Billion-Ton Report […]

The Digest’s 2025 Multi-Slide Guide to Renewable Chemicals & Materials

July 16, 2025 | Jim Lane

Consumer demand for biobased materials is strong, and innovation is rampant with first commercial products becoming more common. Chemicals and materials offer higher margins suitable for early-stage companies. However, the sector faces significant headwinds, including a lack of mandates or tax credits, immature capital markets, slow adoption by formulators, high costs, and scarce production capacity. […]

The Digest’s 2025 Multi-Slide Guide to Syngas for Recarbonization of Industry

July 15, 2025 | Jim Lane

Hard-to-electrify industries require green carbon via REcarbonization, with biomass a sustainable source. Green syngas from lignocellulosic biomass through gasification and pyrolysis is a platform chemical for Sustainable Aviation Fuels (SAF), Green Methanol, and Green Hydrogen. Challenges include scaling FT SAF via green syngas economically/technically, high CAPEX for methanol, and complex biomass pre-treatment and syngas cleanup […]

The Digest’s 2025 Multi-Slide Guide to Renewable Diesel

July 14, 2025 | Jim Lane

Global planned RD/SAF capacity is rising, supported by international mandates like RFS and ReFuelEU Aviation, with accelerating deployment and diverse technologies. Feedstock is generally affordable and available. Major headwinds include slower adoption than goals, a “mandate lite” market, and forecast confusion. A significant headwind is “cost hysteria,” as SAF is much more expensive, with Spanish […]

Free Subscription

The Biofuels Digest newsletter

The most widely-read biofuels daily — 20,000+ organizations subscribe — why not you too?