California's Hydrogen Infrastructure Funding Program

Developing an advanced biofuels industry in California: The alternative and renewable fuel and vehicle technology program

Subsystems of the 2008 Lexus 600h hybrid electric vehicle (HEV) were studied and tested as part of an intensive benchmarking effort carried out to produce detailed information concerning the current state of nondomestic alternative vehicle technologies. Feedback provided by benchmarking efforts is particularly useful to partners of the Vehicle Technologies collaborative research program as it is essential in establishing reasonable yet challenging programmatic goals which facilitate development of competitive technologies. The competitive nature set forth by the Vehicle Technologies program not only promotes energy independence and economic stability, it also advocates the advancement of alternative vehicle technologies in an overall global perspective. These technologies greatly facilitate the potential to reduce dependency on depleting natural resources and mitigate harmful impacts of transportation upon the environment.

While aircraft account for less than 10% of United States (U.S.) transportation energy consumption, it is the only mode expected to see sustained growth in energy demand through 2050. Currently, commercially available aircraft rely heavily on either jet fuel or leaded aviation gasoline. Over the past few decades, concerns have grown over the contributing effects that greenhouse gases, which are produced from fossil fuels, have on the environment. Due to these concerns, many aircraft manufacturers are pursuing the development of new generation aircraft that can leverage alternative, renewable fuels. The Federal Aviation Administration (FAA) is presently working toward certifying multiple novel aircraft and developing an environment to safely support this innovation. For airports and aircraft original equipment manufacturers (OEMs) that choose to be early adopters of hydrogen technology, the FAA needs to provide guidance for the associated support infrastructure. The FAA is collaborating with the National Renewable Energy Laboratory (NREL) on this research project to evaluate the impact of the anticipated demand for hydrogen as a fuel source on existing airport infrastructure. This study is intended to help reduce market barriers involving uncertainty in standards and operational requirements of hydrogen technology and airport infrastructure. By defining system-wide best practices in refueling systems and facility layouts, manufacturers, airports, and communities can be better prepared to participate in this emerging industry. Section 2 of this document is the culmination of a literature review that describes the current state and the anticipated future of hydrogen-related technology across various government organizations, industries, and academia. This work identifies existing goals and the maturity level of the industry to help define a realistic strategy and approach to implement hydrogen systems into the airport environment within a realistic timeframe. The technology areas cover production, storage, transport, and fueling as a supply chain of hydrogen. This report also briefly investigates hydrogen propulsion systems, such as fuel cell and combustion engines. Furthermore, this work organizes safety codes and standards to identify gaps in our current understanding. Presently, there are detailed standards regarding hydrogen technology, airport safety, and aircraft fueling. However, they are not consolidated as a unified set of codes and standards suitable for the airport environment. Preventive safety measures and emergency procedures must be identified as hydrogen will begin to be transported on to airport sites. These safety requirements must continue to mature as the airports adopt hydrogen technology in their proximity. Sections 3 and 4 of this study focus hydrogen aircraft demands, and airport infrastructure needed to support hydrogen technology. The examination of hydrogen production, storage requirements, delivery methods, refueling services, and safety requirements are critical to accommodate novel hydrogen aircraft in the airport environment. Learnings are applied to the LAX, SEA, PDX, and SFO airports to gain insight on: 1) space requirements for hydrogen infrastructure, 2) airport hydrogen infrastructure placement, and 3) cost and economic impacts of hydrogen infrastructure at each airport. Results show that each airport has space for hydrogen infrastructure, especially at hydrogen demand levels of around 1,000 kg/day. We also find that both hydrogen infrastructure cost and economic impacts become more favorable as hydrogen demand at the airports scale. This study is intended to provide a comprehensive understanding of hydrogen infrastructure that will enable energy-savings and emissions-reductions while illuminating pathways to transition from legacy systems to next generation aviation. The study should be used as a guide by airport and government officials, as well as industry leaders, to gain insights on how hydrogen and hydrogen infrastructure can be utilized for advance air mobility applications.

Alternative fuels and vehicle technologies for road transport are receiving increasing support as a result of climate change mitigation policies and local air quality regulations. This study attempts to estimate the emission reductions of major air pollutants (NOx, PM, HC and CO 2) that might be expected from the introduction of alternative fuels and technologies in London by the year 2020. A number of alternative scenarios for the road transport system have been developed, and their corresponding emissions compared to those arising from a baseline scenario, consisting exclusively of conventional fuels and engines. The results confirmed that by 2020 the emissions of NOx, PM and HC from a conventional vehicle fleet would be greatly decreased as a result of more stringent vehicle emission standards. Significant additional improvements could be achieved by the introduction of hydrogen-fuel cell vehicles, hybrid electric vehicles, natural gas and biofuels. It was found that the emissions of the principal pollutants of concern in London, NOx and PM 10, show similar patterns of reduction. The results also imply that the anticipated increase in conventional vehicle efficiency would only deliver a minimal 2 percent reduction in CO 2 vehicle emissions relative to the present, but greater reductions were achieved in all the alternative scenarios.

This study presents a methodology for estimating high-resolution, regional on-road vehicle emissions and the associated reductions in air pollutant emissions from vehicles that utilize alternative fuels or propulsion technologies. The fuels considered are gasoline, diesel, ethanol, biodiesel, compressed natural gas, hydrogen, and electricity. The technologies considered are internal combustion or compression engines, hybrids, fuel cell, and electric. Road link-based emission models are developed using modal fuel use and emission rates applied to facility- and speed-specific driving cycles. For an urban case study, passenger cars were found to be the largest sources of HC, CO, and CO(2) emissions, whereas trucks contributed the largest share of NO(x) emissions. When alternative fuel and propulsion technologies were introduced in the fleet at a modest market penetration level of 27%, their emission reductions were found to be 3-14%. Emissions for all pollutants generally decreased with an increase in the market share of alternative vehicle technologies. Turnover of the light duty fleet to newer Tier 2 vehicles reduced emissions of HC, CO, and NO(x) substantially. However, modest improvements in fuel economy may be offset by VMT growth and reductions in overall average speed.

In the realm of internal combustion engines, there is a growing utilization of alternative renewable fuels as substitutes for traditional diesel and gasoline. This surge in demand is driven by the imperative to diminish fuel consumption and adhere to stringent regulations concerning engine emissions. Sole reliance on experimental analysis is inadequate to effectively address combustion, performance, and emission issues in engines. Consequently, the integration of engine modelling, grounded in machine learning methodologies and statistical data through the response surface method (RSM), has become increasingly significant for enhanced analytical outcomes. This study aims to explore the contemporary applications of RSM in assessing the feasibility of a wide range of renewable alternative fuels for internal combustion engines. Initially, the study outlines the fundamental principles and procedural steps of RSM, offering readers an introduction to this multifaceted statistical technique. Subsequently, the study delves into a comprehensive examination of the recent applications of alternative renewable fuels, focusing on their impact on combustion, performance, and emissions in the domain of internal combustion engines. Furthermore, the study sheds light on the advantages and limitations of employing RSM, and discusses the potential of combining RSM with other modelling techniques to optimise results. The overarching objective is to provide a thorough insight into the role and efficacy of RSM in the evaluation of renewable alternative fuels, thereby contributing to the ongoing discourse in the field of internal combustion engines.

This report describes the data gathering and analysis procedures that support the US Department of Energy's implementation of the Alternative Motor Fuels Act (AMFA) of 1988. Specifically, test procedures, analytical methods, and data protocols are covered. The aim of these collection and analysis efforts, as mandated by AMFA, is to demonstrate the environmental, economic, and performance characteristics of alternative transportation fuels.

The Collaborative Advanced Gas Turbine (CAGT) Program is an advanced gas turbine research and development program whose goal is to accelerate the commercial availability, to within the turn of the century, of high efficiency aeroderivative gas turbines for electric power generating applications. In the first project phase, research was conducted to prove or disprove the research hypothesis that advanced aeroderivative gas turbine systems can provide a promising technology alternative, offering high efficiency and good environmental performance characteristics in modular sizes, for utility applications. This $5 million, Phase 1 research effort reflects the collaborative efforts of a broad and international coalition of industries and organizations, both public and private, that have pooled their resources to assist in this research. Included in this coalition are: electric and gas utilities, the Electric Power Research Institute, the Gas Research Institute and the principal aircraft engine manufacturers. Additionally, the US Department of Energy (DOE) and the California Energy Commission have interacted with the CAGT on both technical and executive levels as observers and sources of funding. The three aircraft engine manufacturer-led research teams participating in this research include: Rolls-Royce, Inc., and Bechtel; the Turbo Power and Marine Division of United Technologies and Fluor Daniel; and General Electric Power Generation, Stewart and Stevenson, and Bechtel. Each team has investigated advanced electric power generating systems based on their high-thrust (60,000 to 100,000 pounds) aircraft engines. The ultimate goal of the CAGT program is that the community of stakeholders in the growing market for natural-gas-fueled, electric power generation can collectively provide the right combination of market-pull and technology-push to substantially accelerate the commercialization of advanced, high efficiency aeroderivative technologies.

While the previous chapter addressed the build-up of a hydrogen infrastructure in Europe, this chapter focuses on implementing a hydrogen infrastructure in the USA, where, over the last decade, the vision of hydrogen as a future transportation fuel has gained remarkable momentum.

<div class="htmlview paragraph">This paper describes the recently established Commercial Aviation Alternative Fuel Initiative (CAAFI), including its goals and objectives, as well as presents an alternate fuel roadmap that was originally generated by industry and refined by the CAAFI stakeholders.</div> <div class="htmlview paragraph">CAAFI is designed to coordinate the development and commercialization of “drop-in” alternate fuels (i.e. fuels that can directly supplement or replace crude oil derived jet fuels), as well as exploring the long-term potential of other fuel options. The ultimate goal is to ensure an affordable and stable supply of environmentally progressive aviation fuels that will enable continued growth of commercial aviation.</div> <div class="htmlview paragraph">This initiative is organized into four sub-groups: Research and Development (R&D), certification, environment, and economics & business. The R&D group seeks to identify promising new drop-in alternate fuels, and to foster coordination of development efforts. The certification group is creating a streamlined common approach to the certification of alternate fuels. The environmental group is addressing well to wake and life-cycle implications associated with synthetic and renewable alternative jet fuels. The economics and business group is helping to determine how these fuels can provide fuel suppliers and airline operators with a sound business case.</div>

Various endeavors are undertaken by the maritime industry, academia, and policy-makers to reduce greenhouse gas emissions. These include the search for feasible technologies that could be used onboard merchant vessels and are propelled by international legal and social initiatives. To this end, this study aimed to critically analyze the research trends pertaining to the active methods of reducing the negative environmental impact of shipping. The research is focused on alternative fuels and renewable energy systems with respect to the related policy-making and existing legal framework. Therefore, a bibliometric approach was applied to a sample of 234 scientific papers indexed in the SCI-EXPANDED in Clarivate Analytics Web of Science Core Collection. The results indicate that the scientific efforts were made more on alternative fuels, while renewable energy sources only recently became a popular research subject. Moreover, the environmental benefits of prospective technologies are more investigated than their financial aspects. The research effort on alternative maritime fuels was made in parallel with the legal one, both aiming to combat global climate change and magnifying each other.

On the road to fossil-free public transport: The case of Swedish bus fleets

Valorization of agricultural wastes for biofuel applications

Techno-economic review of alternative fuels and propulsion systems for the aviation sector

Characterization of high heating-rate chars from alternative fuels using an electrodynamic balance