Alternate Fuel Vehicles

Optimized PV-coupled Battery Systems for Combining Applications: Impact of Battery Technology and Geography

Pena-Bello, A.
Barbour, E.
Gonzalez, M. C.
Patel, M. K.
Parra, D.
2019

Interest in residential batteries to supply photovoltaic (PV) electricity on demand is increasing, however they are not profitable yet. Combining applications has been suggested as a way to increase their attractiveness, but the extent to which this can be achieved, as well as how the different value propositions may affect the optimal battery technology, remain unclear. In this study, we develop an open-source optimization framework to determine the best-suited battery technology depending on the size and the applications combined, including PV self-consumption, demand load-shifting,...

Towards Resilient Critical Infrastructures: Understanding the Impact of Coastal Flooding on the Fuel Transportation Network in the San Francisco Bay

He, Yiyi
Lindbergh, Sarah
Ju, Yang
Gonzalez, Marta
Radke, John
2021

Sea level rise (SLR) and storm surge inundation are major concerns along the coast of the San Francisco Bay (the Bay Area), impacting both coastal communities and critical infrastructure networks. The oil industry comprises a complex and critical infrastructure network located in the Bay Area. There is an urgent need to assess consequences and identify risk-based solutions to increase the resilience of this industrial network in the Bay Area to SLR and storm surge. In this study, a comprehensive multi-modal network model representing the fuel supply system was built. A total of 120 coastal...

Evaluating Air Carrier Fuel Efficiency and CO2 Emissions in the U.S. Airline Industry

Zou, Bo
Elke, Matthew
Hansen, Mark
2012

We employ ratio-based, deterministic, and stochastic frontier approaches to investigate fuel efficiency among 15 large jet operators (mainline airlines) in the U.S. Given the hub-and-spoke routing structure and the consequent affiliation between mainline and regional carriers, we consider not only fuel efficiency of individual mainline airlines, but also the joint efficiency of each mainline and its regional subsidiaries, as well as fuel efficiency of mainline carriers in transporting passengers from their origins to destinations. We find that: 1) airline fuel consumption is highly...

Fueling for Contingencies: The Hidden Cost of Unpredictability in the Air Transportation System

Hao, Lu
Hansen, Mark
Ryerson, Megan S.
2016

The aviation community is increasing its attention on the concept of predictability when conducting aviation service quality assessments. Reduced fuel consumption and the related cost is one of the various benefits that could be achieved through improved flight predictability. A lack of predictability may cause airline dispatchers to load more fuel onto aircraft before they depart; the flights would then in turn consume extra fuel just to carry excess fuel loaded. In this study, we employ a large dataset with flight-level fuel loading and consumption information from a major US airline....

Estimating Fuel Burn Impacts of Taxi-out Delay with Implications for Gate-hold Benefits

Hao, Lu
Ryerson, Megan S.
Kang, Lei
Hansen, Mark
2017

The aviation community is actively investigating initiatives to reduce aircraft fuel consumption from surface operations, as surface management strategies may face fewer implementation barriers compared with en route strategies. One fuel-saving initiative for the air transportation system is the possibility of holding aircraft at the gate, or the spot, until the point at which they can taxi unimpeded to the departure runway. The extent to which gate holding strategies have financial and environmental benefits hinges on the quantity of fuel that is consumed during surface operations. A...

Improving Airline Fuel Efficiency via Fuel Burn Prediction and Uncertainty Estimation

Kang, Lei
Hansen, Mark
2018

Reducing fuel consumption is a unifying goal across the aviation industry. One fuel-saving opportunity for airlines is the possibility of reducing discretionary fuel loading by dispatchers. In this study, we propose a novel discretionary fuel estimation approach that can assist dispatchers with better discretionary fuel loading decisions. Based on the analysis on our study airline, our approach is found to substantially reduce unnecessary discretionary fuel loading while maintaining the same safety level compared to the current fuel loading practice. The idea is that by providing...

Time to Burn: Flight Delay, Terminal Efficiency, and Fuel Consumption in the National Airspace System

Ryerson, Megan S.
Hansen, Mark
2014

Improved Air Traffic Management (ATM) leading to reduced en route and gate delay, greater predictability in flight planning, and reduced terminal inefficiencies has a role to play in reducing aviation fuel consumption. Air navigation service providers are working to quantify this role to help prioritize and justify ATM modernization efforts. In the following study we analyze actual flight-level fuel consumption data reported by a major U.S. based airline to study the possible fuel savings from ATM improvements that allow flights to better adhere to their planned trajectories both en route...

The Potential of Turboprops for Reducing Aviation Fuel Consumption

Ryerson, Megan Smirti
Hansen, Mark
2010

To assist in aviation systems planning in the context of fuel price uncertainty and environmental regulation, we take a total logistics cost approach and evaluate three representative aircraft (narrow body, regional jet, and turboprop) for operating and passenger preference costs over a range of fuel prices. Homogenous fleets of each vehicle category are compared for operating and passenger costs over a range of fuel prices and route distances and the minimum cost fleet mix is determined. In general, as fuel prices increase, the turboprop offers a lower operating cost per seat over a wider...

Capturing the Impact of Fuel Price on Jet Aircraft Operating Costs with Leontief Technology and Econometric Models

Ryerson, Megan Smirti
Hansen, Mark
2013

Investigation of the airline response to a fuel price increase is in effect an investigation of the role of variable interactions in aircraft cost models. We examine the impact of fuel price on aircraft costs and airline operational strategies by developing two classes of operating cost models for jet aircraft and comparing the results. The translog operating cost model is a flexible functional form that provides a detailed representation of the empirical relationship between fuel cost and operating cost, allowing for substitution, scale, aircraft age, and variable interactions to be...

Capturing the Impact of Fuel Price on Jet Aircraft Operating Costs with Engineering and Econometric Models

Smirti Ryerson, Megan
Hansen, Mark
2009

Challenges in forecasting fleet development and deployment are in part due to fuel price uncertainty. To address this issue, a recent study developed an aircraft-specific Leontief technology operating cost model (LM) to compare aircraft costs under fuel price uncertainty. This model considers individual aircraft types to be Leontief technologies, such that the key drivers of cost must be used in fixed quantities. While asserted in the literature that models in this form can more accurately predict operating costs, the Leontief specification precludes a precise examination of how aircraft...