Energy, economic, and environmental benefits assessment of co-optimized engines and bio-blendstocks

Abstract

A systems-level modeling suite underpins estimates of greenhouse gas and other benefits of deploying co-optimized fuels and engines.

The contribution of biomass and waste resources to decarbonizing transportation and related energy and environmental effects

“…16 However, circular-economy strategies will increase battery recycling, which will help meet the demand for these resources. 45 Other signicant areas of impact are the potential investments needed for these transitions in terms of capital investment for biofuel production facilities, 12 investment/time to convert the LD eet to electric, and additional electricity generation and distribution infrastructure. However, with dropin-fuels like renewable diesel, for example, which is compatible with most existing engines with little or no modication, the impact on vehicle owners and manufacturers may be minimal.…”

“…Their results indicate that 446 million tons of GHG emissions could be avoided in 2030 with biomass resources. Dunn et al 12 evaluated changes in GHG emissions, energy and water consumption, and criteria air pollutant emissions in the light-duty (LD) sector when biofuels that increase combustion engine efficiency are deployed. In their study, cumulative emissions reductions reached 7% in 2050.…”

Synthesizing Clean Transportation Fuels from CO2 Will at Least Quintuple the Demand for Non-carbogenic Electricity in the United States

“…With a projected net energy conversion efficiency to a renewable fuel of about 80%, that amount of renewable feedstock would have a heating value of about 7.5 EJ which is about 25% of the 30 EJ/year used today by the transportation sector, an optimistic estimate compared to that by Rogers et al The use of biomass-derived fuels with co-optimized engines would be limited by that optimistic estimate of the availability of the fuel. Indeed, co-optimization is projected to offer, at best, <10% decrease in cumulative GHG emissions by 2050 for light-duty vehicles over use of biofuels with today’s engines. That projection assumes a 31% blend of a biofuel, such that the final fuel had a 26% lower GHG emission intensity relative to a petroleum gasoline (E0).…”

“…Three approaches have been mooted to operate the current and near-future fleet of transportation vehicles with significantly less production of greenhouse gases (GHGs): renewable fuels, electrofuels, and electric vehicles recharged using renewably generated electricity. We use the term “electrofuel” to denote the combining of renewably sourced carbon, hydrogen, and renewably sourced electrical energy to generate liquid fuels that could be used in today’s vehicles or with powertrains specifically optimized for their use (co-optimization of fuels and engines , ). Alternately, renewably sourced electricity could directly recharge all-electric powertrains (or the battery of plug-in hybrid vehicles).…”

Designed to Be Green, Economic, and Efficient: A Ketone‐Ester‐Alcohol‐Alkane Blend for Future Spark‐Ignition Engines

“…For advanced spark‐ignition (SI) engines, ethanol is an attractive fuel as it possesses a high knock‐resistance, which can be attributed to three properties: a high research octane number (RON), a high enthalpy of vaporization, and a high laminar burning velocity [7] . It is often regarded as a prototype fuel for high‐efficiency SI engines [8,9] . However, as a neat fuel, ethanol can cause problems in engine cold start and cold run as its high enthalpy of vaporization and low volatility complicate in‐cylinder mixture formation under challenging boundary conditions [8,10,11] …”