SYST 490
Final Report
Fall 2011
The Design of a Carbon Neutral Airport
Joel Hannah, Danielle Hettmann, Naseer Rashid,
Chris Saleh, Cihan Yilmaz
Department of Systems Engineering and Operations Research
George Mason University, Fairfax, VA
Contents
Context .......................................................................................................................................................... 2
Airport Operations .................................................................................................................................. 4
Stakeholder Analysis ..................................................................................................................................... 6
Problem ....................................................................................................................................................... 11
Need Statement.................................................................................................................................... 11
Statement of Work ............................................................................................................................... 12
Mission Requirements ................................................................................................................................ 13
Scope ........................................................................................................................................................... 14
Geographic Scope ............................................................................................................................... 14
Operations Scope................................................................................................................................. 15
Emissions Scope .................................................................................................................................. 16
Method of Analysis ..................................................................................................................................... 17
Inventory ................................................................................................................................................ 17
Risk ......................................................................................................................................................... 19
Limitations ............................................................................................................................................. 20
Design Alternatives ..................................................................................................................................... 20
Proposed Alternatives for Ground Access Vehicles (GAV) ........................................................... 21
Proposed Alternatives for Ground Support Equipment (GSE) ...................................................... 22
Proposed Alternatives for Aircraft and APU ..................................................................................... 22
Proposed Alternatives for Stationary Sources ................................................................................. 24
Design of Experiment .................................................................................................................................. 25
Project Plan ................................................................................................................................................. 26
Proposed Work for SYST495 ....................................................................................................................... 27
Bibliography ................................................................................................................................................ 32
Definitions and Acronyms ........................................................................................................................... 34
Appendix A: Emissions Indices .................................................................................................................... 35
1
Context
Concerns continue to increase over potential effects of anthropogenic (or human-made)
activities on earth’s climate particularly those activities contributing to the rising concentrations
of greenhouse gas (GHG) emissions. Looking at emissions since the industrial revolution in
1850, there has been an increase in carbon dioxide concentration and an increase in global
temperature relative to this carbon dioxide level. This data can be seen in Figure 1: Global
Temperature and Carbon Dioxide Concentrations.
Figure 1: Global Temperature and Carbon Dioxide Concentrations
Aviation is currently responsible for 3.63% of United States greenhouse gas emissions (EPA)
and 2% of global CO2 emissions (IPCC, 2004). While this is a small percentage of the GHG
emissions globally, the emissions from aviation related activities has a direct impact into the
atmosphere and are concentrated in high traffic area.
Political and community concerns have grown in response to these studies.
Internationally, the primary response to these concerns is the Kyoto Protocol. The Protocol is
an environmental treaty with the goal of reducing climate change through the stabilization of
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anthropogenic emissions. The Protocol commits to reduce or trade emissions and represents a
promise by the participating governments to reduce GHG emissions by an average of 5.2% of
the 1990 levels. These GHG’s emissions include carbon dioxide (CO2), methane (CH4), nitrous
oxide (N2O), sulfur hexafluoride (SF6), hydrofluorocarbons (HFC), and perfluorocarbons (PFC).
The targets set by the Kyoto Protocol included aviation emissions, but only those related to
domestic travel. As of September 2011, around the world, 193 parties (192 States and 1
regional economic integration organization) are a part of the Kyoto Protocol. The United States
has been involved in the Protocol legislation since the creation but remains a signatory and has
not ratified the treaty. Over the past Presidential administrations, there has been a commonly
accepted understanding that the United States would not ratify the treaty until there are
quantitative emissions commitments for developing countries, such as China1. Since the limits
are based on the size of a country’s land, carbon trading may become financially advantageous
to geographically large countries with low population density, such as Russia. Most of the
provisions in the treaty only apply to developing countries which is a direct violation of the ByrdHagel Resolution wherein the US cannot sign any agreement that does not have fair guidelines
for all countries (STERN, 2007). In the United States, federal legislation has yet to be developed
to regulate mobile aviation-related GHG emissions. State and local governments have
responded to concerns by developing policies to control the amount of GHGs generated by
airport operations. Voluntary registries, such as The Climate Registry, on the national and
regional level have been established to promote meeting Kyoto goals.
Several states have developed state-based laws that require inventories of greenhouse
gas emissions. In 2006, the California Air Resources Board (CARB) was created with the goal
of reducing GHG emissions in California through 2020 (ARB Mission and Goals, 2009). The first
part was setting caps for emissions levels in major industries and requiring participation in the
California Climate Action Registry (CCAR). Other legislation includes the Massachusetts
Environmental Policy Act (MEPA), and Washington State’s Environmental Policy Act (SEPA).
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These policies have led to discussions about who has authority to regulate GHG emissions. In
2007, it was declared by the U.S. Supreme Court that the United States Environmental
Protection Agency (USEPA or EPA) has authority over GHG regulations and that the USEPA
must begin to exercise the authority. This ruling increased pressure on the USEPA to regulate
emissions under the Clean Air Act (CAA).
The National Ambient Air Quality Standards (NAAQS) was established under the CAA to
set limits on concentrations of particulate matter in outdoor spaces. The limits are set on
pollution sources and vary depending on geographic location and air flow conditions. The
NAAQS are set for six pollutants defined as “criteria” pollutants: carbon monoxide, lead,
nitrogen dioxide, ozone, particulate pollution, and sulfur dioxide. Inventories are taken annually.
Compliance to the standards makes a region an “attainment” area. Non-compliance earns the
title of “non-attainment”. Non-attainment areas are required to implement a plan to meet NAAQS
or risk losing federal financial assistance.
These policies are a response to public concern of the effects of increasing energy
consumption on the planet. The end goal of the policies referring to GHG emissions is carbon
neutrality, where the net GHG emissions in an area created by human activity is close to zero,
relative to a determined baseline level. Airports have to report air quality statistics from
stationary sources under NAAQS. Trends in policy indicate a move towards controlling
byproducts of energy consumption, including GHG emissions, from both stationary and nonstationary sources.
Airport Operations
From the surrounding communities, passengers and employees flow-in to the airport
through the use of personal cars, public transportation, and airplanes. Passengers then leave
on similar sources, through personal cars, public transportation, and airplanes. The case study
of this project will be Washington Dulles International Airport (IAD) of the Metropolitan
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Washington Airports Authority (MWAA). IAD consists of 127 airline gates with five concourses:
A, B, C, D, and Z. The airport always operates an AeroTrain system and mobile lounges to
transport passengers and employees between the concourses. IAD has a total of four runways
to accommodate the increasing traffic off aviation (Metropolitan Washington Airports Authority,
2011).
Dulles International Airport is serviced by two major roadways: VA-route 28 and the
Dulles Toll Road (VA-Route 267). Ground access vehicles include: personal vehicles, taxis, and
public transportation such as buses and other mass transportation. All of the economy and
some of the employee parking lots are serviced by MWAA controlled shuttle buses. Employees
have 7 parking lots: North, East, East Reserve, West Reserve, Cargo, CBP, and L S G (in-flight
service provider). Public parking lots include: Economy, Daily Garage 1, Daily Garage 2, Hourly,
and Valet. There are 24,000 total public parking spaces available at Dulles. (Metropolitan
Washington Airports Authority, 2011)
Bottle necks occur during airport operations in the flow of aircraft and ground access
vehicles. With aircraft there are delays which include: gate push back, departure congestion,
and taxi times. For ground access vehicles delays include: congestion on roads servicing airport
and increased idling time at arrivals/departures. Bottlenecks cause an increase in emissions
through the increased engine use of both aircraft and ground access vehicles. Optimization of
airport flow would assist in overall reduction of GHG emissions.
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Stakeholder Analysis
There are three levels of stakeholders involved in airports with regards to GHG
emissions. The first level of this is the decision makers, including the federal government, local
government, and non-government organizations (NGO). The second level of stakeholders
follows the decisions made by the first level. This level includes airport management, air
carriers, air service providers, ground transportation, and airport services. The third level of
stakeholders is the bystanders. These bystanders, or victims, are not decision makers or those
who conform to the decisions, but rather the people or entities who perform the day-to-day
operations implied by the actions of the first and second level stakeholders. These stakeholders
include passengers, employees, and surrounding communities.
Within the primary stakeholders, there are two main points of view: business decision
verse an environmental decision. The business decision focuses on lowering cost, increasing
revenue, and maximizing profit. An environmental view of a decision focuses on minimizing the
effect of a decision on the community. This effect also includes an emphasis on environmental
impact. These two views create tension as the two views often do not produce the same results.
Another issue arises when identifying whose responsibility it is to consider the environmental
decision. A business decision produces the more desirable immediate, tangible
result. Consequently, environmental impacts have a long, intangible result and are given little
weight when considering changes to airport operations.
To emphasize the value of environmental decisions the Social Cost of Carbon (SCC) is
a valuable metric. The SCC is a notional value for emitting an extra ton of CO2 at any time. The
average cost is $43 per metric ton of CO2 per person. This impact includes changes in
agricultural productivity, human health, property damages, and other ecosystem changes.
Monetizing the impact of CO2 emissions allows for analysis based on benefits of environmental
decisions. (Intergovernmental Panel on Climate Change, 2007)
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Figure 2: Stakeholder Interaction Diagram
Airport Stakeholder Interactions Model Overview:
The model of airport organization is shown through boundaries between different entities
of airport operations. Such boundaries include the airport organizational boundary, airport
service boundary, capital improvement bill payers, and local economy and community. The
airport organization boundary is controlled by the airport management which is partly controlled
by the airport board. The airport management has control over the infrastructure of the airport
and operational procedures. They do not have control over services provided within the airport
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infrastructure. The airport service boundary is all of the services provided at an airport
regardless of the organization that has responsibility and control over that service.
Figure 3: Stakeholder Interactions - Emissions
There are several system loops in the airport stakeholder model. The first is an
emissions feedback track, seen in Figure 3: Stakeholder Interactions - Emissions . Emissions
are generated within the airport service boundary from airport operations, airport infrastructure,
and service providers. These emissions directly affect the local economy and community
through increased noise and pollutants entering the environment. For the purposes of this study,
only emissions will be considered, not noise. These local communities hold voting power over
the local government which governs the airport board. This airport board directly affects the
airport organizational boundary through airport management and operations. The airport
organizational boundary dictates the capacity for service providers to operate within the airport
service boundary which cycles back to the amount of operations generating emissions. This
cycle is designed to have a very weak feedback loop through the stakeholder model since
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emissions have a slow effect on the surrounding environment and the time needed for these
effects to be felt through the election process and into airport management is a very long cycle.
Figure 4: Stakeholder Interactions - Business
There is also a financial or business decision feedback loop that exists in the airport
stakeholder model, seen in Figure 4: Stakeholder Interactions - Busines. Airports depend on
both capital and operating revenues to pay for capital projects and operating expenses. The
feedback loop has interactions between passengers, local economy and communities, and
businesses. This feedback loop is the strongest in response time due to financial decisions and
can have runaway growth since other loops are weak.
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Figure 5: Stakeholder Interaction - Legislation
The final feedback loop shows the legislative interaction with the stakeholders, seen in
Figure 5: Stakeholder Interaction - Legislation. This shows the government/capital improvement
funding. MWAA serves as the airport manager for Dulles International Airport. The MWAA
Board of Directors consists of 13 members. Five members are appointed from the Governor of
Virginia, three from the Mayor of the District of Columbia, two from the Governor of Maryland,
and three from the President of the United States. Regulators, which include: FAA, TSA,
Federal Government, Local Government, and NGOs, provide legislation for aviation which must
be enforced. The conflicting objectives create tension between stakeholders in decision making.
This feedback loop also includes the elections and government stakeholders. These
stakeholders create tension in the feedback loop through decisions that can impact funding
available through the capital improvement finds to the airport. The feedback loop has a very
slow response time.
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Problem
Existing legislation in the United States, including the Kyoto Protocol and NAAQS,
require the monitoring of air pollutants in stationary sources in aviation to improve the air quality
with respect to a target fixed by legislation. Presently, there is no legislation for aviation in the
continental United States which imposes caps for greenhouse gas emissions from stationary
and non-stationary sources involved in aviation. Analysis of policy from Europe regarding
capping of emissions suggests that the increasing awareness of global energy use and its
impact on the environment will prompt the United States to create similar laws for emissions
from aviation. Since there is currently no legislation against all of the sources of emissions from
aviation, there is no way to assign penalty for those sources with the largest amount of
emissions and assign fines to these specific sources. With no feedback loop for penalties, there
is a conflicting stakeholder opinion of who should own the overall problem. No ownership of the
identified problem leads to no one absorbing the cost and time to make changes and no
significant changes can occur.
As the global economy becomes more aware of the impact of greenhouse gas
emissions from both stationary and non-stationary sources within aviation, there will be a desire
to reduce the impact of greenhouse gas emissions from these sources. To achieve a reduced
impact on the environment, the aviation sector of industry will work toward a carbon neutral
state in which there is no net emission of greenhouse gases. This implies that the total amount
of gases emitted will be equal to the total amount of gases sequestered or offset. Due to the
lack of legislation currently in place, there is not a tool which allows for the collection and
analysis of stationary and non-stationary emissions.
Need Statement
In order to reach a carbon neutral state for airports, the total amount of CO2 emissions
must first be determined. A system to collect and report total CO2 emissions for stationary and
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non-stationary sources at airports is needed. This system should be able to receive input,
calculate CO2 emissions, analyze data to identify sources to reduce emissions output and verify
compliance with emissions caps.
As the global economy becomes more aware of the impact of greenhouse gas
emissions from both stationary and non-stationary sources within aviation, there will be a desire
to reduce the impact of greenhouse gas emissions from these sources. To achieve a reduced
impact on the environment, it is projected that the aviation sector of industry will work toward a
carbon neutral state in which there is no net emission of greenhouse gases. This implies that
the total amount of gases emitted will be equal to the total amount of gases offset. Due to the
lack of legislation currently in place, there is not a tool which allows for the collection and
analysis of stationary and non-stationary emissions. There exists a need for a tool to collect and
report GHG emissions of stationary and non-stationary sources at airports.
Statement of Work
In order to move towards a carbon neutral airport several aspects of the airport must be
explored. First you have to see how much is currently being put out. To do this, previous
inventory methods and results have to be surveyed. The tools used in these inventories also
have to be surveyed. From there an inventory tool has to be developed to account for stationary
and non-stationary aviation emissions. This tool will be used to the current status of total
emissions and to identify emissions by source. Those results will be used to set goals for
emissions reduction. Various strategies will be considered for reducing GHG emissions from all
sources. The strategies will be analyzed to determine the most effective and beneficial solution.
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Mission Requirements
Mission requirements derived from the sponsor statement of work are as follows:

The system shall report total aviation related CO2 emissions for stationary and nonstationary sources

The system shall account for aviation related emissions within the boundary of the
landing/take-off (LTO) cycle around the airport.

The system shall report GHG emissions by source.

The system shall calculate emissions within 1.1% accuracy for each emissions source.*

The system shall provide structure for additional GHGs to be calculated.
*Based on magnitude of sample calculations.
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Scope
The scope of the project is decomposed into geographic, operations, and emissions scope.
Geographic Scope
The scope of this project is geographically limited to airport operations within the landing
and take-off (LTO) cycle below mixing altitude. The mixing altitude is the where pollutant mixing
and chemical reaction occurs in the atmosphere. Above the mixing altitude, pollutants do not
mix with ground level emissions and have little effect on ground level concentrations. The
geographic scope covers a radius of 12 nautical miles (22 km) and an altitude of 3,000 feet
within the LTO cycle. The LTO, detailed in Figure 6: Landing Take - off Cycle, is divided into five
main operational modes:
1. Approach: the portion of flight from the time the aircraft reaches the mixing height or
3,000 ft altitude and lands and exits the runway;
2. Taxi/idle-in: the time the aircraft is moving on the taxiway system until reaching the gate;
3. Taxi/idle-out: from departure from the gate until taxied to the runway;
4. Take-off: the movement down the runway through lift-off up to about 1,000 ft; and
5. Climbout: the departure segment from takeoff until exiting the LTO cycle.
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Figure 6: Landing Take - off Cycle
Operations Scope
Within the airport boundary, this project will account for all stationary and non-stationary
sources of GHG emissions. Stationary sources include: Boilers (facility, heating, and fuel),
airport fire department training fires, waste management devices (waste disposal and
incinerators), and construction activities. Non-stationary sources are broken up into 3 additional
areas: Aircraft, Ground Support Equipment (GSE), and Ground Access Vehicles (GAV). Aircraft
accounts for all aviation related emissions including their Aircraft Power Units (APU). GSE
accounts for emissions for airport related activities including: tugs, catering trucks, transporters,
fuel tankers, and passenger boarding stairs. GAVs include all non-airport related emission
activities including: personal passenger vehicles, and public transportation such as taxis, buses,
and trains.
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Emissions Scope
This project will only measure the output of Carbon Dioxide (CO2), based on Figure 7:
Greenhouse Gas Decomposition, CO2 accounts for 83% of the total United States GHG
emissions. Because the majority of GHG emissions are CO2 the tool will be limited to outputting
CO2 measurements. To calculate CO2 emissions, the tool will convert total fuel consumption
and fuel economy into tons of CO2 using predefined equations.
2009 Greenhouse Gas Emissions by Gas
(percentages based on CO2 equivalent)
2.2%
4.5%
10.3%
83.0%
CO2
CH4
N2O
HFCs, PFCs & SF6
Figure 7: Greenhouse Gas Decomposition
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Method of Analysis
Inventory
In order to evaluate solutions for reduction of GHG emissions, a tool is needed to
evaluate the current state of emissions. The Airport Inventory Tool (AIT) is used to inventory
stationary and non-stationary aviation-related GHG emissions within the LTO boundary around
an airport.
Figure 8: Airport Inventory Tool
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An overview of the AIT is in Figure 8: Airport Inventory Tool. The AIT calculates total carbon
emissions based on fuel consumption and the appropriate emissions index. There are two
methods for finding the amount of fuel consumed by non-stationary sources. The first method is
the most preferred method. It uses total fuel consumption from stationary, GAV, GSE, and
aircraft sources. If fuel consumption data are not available, a second method may be used. The
second method for calculation is uses fuel economy information and distance travelled to
calculate emissions from GAV, GSE and aircraft sources. Emissions indices are based on the
type of fuel consumed by the source and are provided by, the Energy Information Administration
(EIA), Environmental Protection Agency (EPA), and Department of Energy (DoE). These
emissions indices values can be found in Appendix A.
For GAV and GSE sources, the total of emissions is calculated using the number of
vehicles, amount of fuel burned, and the appropriate emissions index. If it is known, the actual
amount of fuel consumed is calculated. If the amount is not known, the amount of fuel
consumed is calculated using the distance travelled and average fuel burn rate for each vehicle
or vehicle class.
Equation 1: Emissions = ∑𝑖 𝑓𝑖 ∗ 𝐸𝑖
fi: GAV/GSE fuel consumed; Ei: Emissions Index
Aircraft emissions are calculated using the amount of fuel burned and the fuels appropriate
emissions index. If fuel consumption data is not available, the amount of fuel used can be
calculated using averages based on the model or type aircraft and the number of landings and
take-offs. Obtaining the fleet mix of the airport in question is important in calculation aircraft
emissions under the alternative method. In the event the fleet mix is not available, accepted
distributions of aircraft types may be obtained using the Seattle-Tacoma emissions inventory.
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Equation 2: Emissions =
∑𝑗 𝑓𝑗 ∗ 𝐸𝑗 + ∑𝑘 𝑓𝑘 ∗ 𝐸𝑘
fj: landing aircraft fuel consumed; Ej: landing aircraft emissions index; fk: take-off aircraft fuel
consumed; Ek: take-off aircraft emissions index
Stationary source emissions (See Appendix with stationary sources) are only calculated using
the total fuel consumption method because NAAQS requires annual reporting of stationary
source emissions and fuel consumption. The total emissions for each stationary source will be
calculated using the total fuel consumed and the appropriate emissions index. If there are
multiple fuel types being consumed by one source, each fuel input is considered treated as a
separate input in the AIT.
Equation 3: Emissions = ∑𝑚 𝑓𝑚 ∗ 𝐸𝑚
fm: stationary source fuel consumed; Em: stationary source emissions index
Risk
The risks associated with emissions inventories are data availability and data reliability.
Data Availability
Specific data related to fuel consumption and airport operations is not publically
available for use in the development of the AIT. After development, the process of data
collection will be outside of the scope of the AIT and will be the responsibility of the airport
manager. Therefore, data is needed to validate the AIT development to ensure that emissions
indices and fuel usage data are correct. To validate these values, acceptable distributions from
previous inventories performed at Seattle-Tacoma and Denver International Airports will be
used to determine fleet distributions and ground access vehicle distributions as well as accepted
averages for aircraft and associated ground service equipment fuel consumption.
Data Reliability
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Some of the input, calculations, and emissions indices used in the tool may not be
accurate enough to meet accuracy requirements for the system. To mitigate this risk, previous
inventory inputs and results, such as Seattle-Tacoma and Denver International Airports, will be
compared to AIT results. Since data specific to Dulles International Airport cannot be released
for public use, inventory results based on Dulles International Airport will be presented to the
airport managers, MWAA for validation. The AIT will also be turned over to MWAA for data entry
and validation, with results being returned to the team without specific data included.
Limitations
Carbon Dioxide emissions account for 83% of total GHG emissions by CO2 equivalency
(IPCC, 2004; Brian Kim, 2009). Due to CO2 being such a large percentage of greenhouse gas
emissions, the AIT focus is a Level-1 Inventory tool as defined in ACRP, which focuses on CO2
emissions, and does not include Methane (CH4), Nitrous Oxide (N2O), Sulfur Hexfluoride (SF6),
Hydrofluorocarbons (HFC), and Perfluorocarbons (PFC).
The purpose of the analysis is to identify emissions sources contained within the airport
operational boundary. Therefore dispersion is not included in the analysis. The analysis follows
the IPCC LTO methodology for calculating aircraft emission which does not include helicopters
in the inventory model. In the case of Dulles International Airport, there are less than 10
helicopter landings and takeoffs per year.
Design Alternatives
The long term goal of carbon neutrality is to achieve a zero carbon footprint relative to a
baseline amount. To create a carbon neutral airport, a tiered approach will be used to reduce
carbon emissions through the use of renewable energy sources and energy efficient
technologies. Figure 9: Carbon Neutral Strategy shows the project strategy to reach carbon
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neutrality.
Reduce energy need
Maximize energy
efficiency
Renewable
Energy
Offset
Figure 9: Carbon Neutral Strategy
Source: The Carbon Neutral Company
The first step of the strategy is to reduce energy need for airports in order to minimize total
carbon emissions at airports. The second step of the carbon neutral strategy is to maximize
energy efficiency in order to minimize energy waste at airports. The third step of the strategy is
to focus on renewable energy and new energy technologies in order to produce electricity in all
or part of the airports. The fourth step of the strategy is to share offset studies in order to share
existing and future offset programs for carbon neutral airports. The reduction strategies are
based on the emissions source classifications: Ground Access Vehicles (GAV), Ground Support
Equipments (GSE), Aircrafts (including APUs), and Stationary Sources.
Proposed Alternatives for Ground Access Vehicles (GAV)
Ground access vehicles are private and commercial motor vehicles used by passengers
and airline & airport employees to travel on airport roadways and in parking lots. The first
proposed alternative for GAVs is to reduce energy need. The first alternative method for energy
reduction is a carpooling program in order to consolidate the number of GAV emissions sources
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per passenger. The second alternative method for energy reduction is establishing a combined
rental car shuttle. For example, there are currently eight rental car companies at Dulles
International Airport which each run their own shuttles to pick up rental customers from the main
terminal. Instead of running eight different shuttles, one energy efficient shuttle could be
implemented for rental car companies. The second proposed alternative for GAVs is investment
in better public transportation in order to encourage passengers to leave their cars at home and
utilize public transportation. Two alternatives for public transportation are Metro (Dulles Metro,
scheduled to open 2013) and hybrid busses. Carpooling programs and better public
transportation will decrease the total number of GAVs at airports and will lower passengers’ total
carbon emissions.
Proposed Alternatives for Ground Support Equipment (GSE)
The strategy for determining alternatives for ground support equipment is categorized
into two major groups based on fuel type (gasoline or diesel) and on-road (vehicles or trucks) or
off-road (tugs, tractors or loaders). GSEs provide services (fuel & baggage loading or
transportation of passengers) to aircrafts between flights. The majority of existing ground
support equipment use gasoline or diesel fuel. The proposed alternative for GSEs is to invest in
new energy technologies. Alternative energy technologies for GSEs are electric, hybrid,
hydrogen and liquid propane. The new technologies will minimize fuel consumption and will
lower GSEs’ total carbon emissions.
Proposed Alternatives for Aircraft and APU
A majority of existing aircrafts and APUs use aircraft fuel (Jet A-1). The first proposed
alternative for aircrafts is to invest in alternative fuels. The first alternative is hydrogen-powered
aircrafts. Hydrogen is an environmentally friendly gas fuel for future aircrafts. It shows a
significant promise as fuel and it is a potential replacement for current aircraft fuel, Jet A-1. The
most significant advantage of hydrogen is that it does not produce any GHG emissions. It is
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lighter than Jet A-1 and thereby maximizes energy efficiency and minimizes carbon emissions
for each flight. The second alternative fuel type is compressed natural gas (CNG). It is a fossil
fuel substitute for gasoline, diesel and propane. It shows a significant promise as fuel and it is a
potential replacement for current aircraft fuel, Jet A-1. The most significant advantage of CNG is
that it produces less greenhouse gases and is more environmentally friendly than the current
fuel, Jet A-1. CNG is lighter than current aircraft fuel, Jet A-1 therefore it maximizes energy
efficiency and minimizes carbon emissions for each flight. The third alternative fuel type is
biodiesel. It is also called vegetable fuel and being used for diesel engines. In 2007, the first
biodiesel military aircraft was tested in Nevada.
The second proposed alternative for aircrafts is fixed ground power. It is an alternative
method to provide aircrafts’ energy consumption on gateways. It provides 400 Hz gate power
and pre-conditioned air therefore aircrafts can switch off their engines and APUs while at the
gate. The largest advantage of fixed ground power is that it is clean energy source and is
environmentally friendly. This technology will significantly reduce the use of APUs and related
carbon emissions.
The third proposed alternative for aircrafts is developing more efficient air traffic
management. One option is utilizing continuous descent approach (CDA) for air traffic
management. It is an optimized landing strategy for aircrafts. It minimizes engine and fuel
usage. Unlike the traditional landing method, CDA minimizes engine trust at 7000 FT and 25
miles away from landing point and does not add any additional trust on engines at 3000 feet
above ground level. This new landing strategy minimizes fuel waste and lowers aircrafts’ total
carbon emissions. Another alternative for reducing aircraft GHG emissions is minimizing taxiing
times. Taxi time is the total time of an aircraft movement on the ground between the gate,
terminal, ramp or runway. Delays, previously discussed as bottlenecks, can increase taxiing
times for aircrafts increasing the emissions expelled into the atmosphere. Shortening taxiing
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times minimizes the total time of an aircraft between the gates, terminals, ramps and runways
and therefore minimizes fuel waste and unnecessary carbon emissions.
Proposed Alternatives for Stationary Sources
Stationary sources include facilities sources such as power generators, steam boilers,
heaters or waste incinerators. Fire training, waste management, and construction activities are
other aviation-related stationary sources. The majority of existing stationary sources use
gasoline, oil or electric. The first proposed alternative for stationary sources is renewable energy
technologies. Solar energy is the most available renewable energy source to produce electricity
through photovoltaic cells at airports. Solar energy can also be used for heating. Based on the
specific area and locations, airports might be able to provide total or part of energy
consumptions by solar energy. Wind energy is the second best available renewable energy
source to produce electricity by wind turbines at airports. Wind turbines convert kinetic energy to
mechanical energy to produce electricity. Depending on the area and locations, airports might
be able to provide total or part of energy consumptions by wind energy. For example, Denver
International Airport is able to produce enough electricity by wind and solar farms in order to
provide their energy consumption (Associates, Rocondo &, 2005). Innovative design in energy
efficient terminals & buildings could be another solution used to reduce or eliminate energy
need and maximize energy efficiency. These designs also include high efficiency boilers,
heating and cooling systems with effective waste management techniques. The most important
step for innovative designs is to reduce energy need and generate energy with environmentally
friendly methods. These new technologies will minimize fuel consumption and will lower
stationary sources’ total carbon emissions.
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Design of Experiment
The design of experiment for Greenhouse Gas Emissions Project is comprised of four
main steps. The first step of our design of experiment is to plug in aviation data in Aviation
Inventory Tool (AIT) in order to collect total carbon emissions from stationary and non-stationary
sources. The second step of our design of experiment is to analyze emissions data from AIT in
order to determine the largest contributions of emissions at airports. The third step of our design
of experiment is to implement proposed alternatives into AIT in order to reduce emissions from
inputs. The fourth step of our design of experiment is to provide recommendations based on
results from third step in order to optimize airports. The design of experiment for Greenhouse
Gas Emissions Project has three weights: Payoff, Difficulty and Cost. We will retrieve weights
based on discussion with MWAA and our stakeholders. The weights will be combined with
proposed alternatives in order to provide recommendations for system optimization and to
determine the best proposed alternative for overall reduction of greenhouse gas emissions and
a step toward carbon neutrality for the airport.
25
Project Plan
This project is comprised of five high level tasks: planning, design/method of analysis,
implement, deliver, and management. The work breakdown structure can be seen in Figure 10:
Work Breakdown Structure. For SYST490, tasks under 1.0 planning have been completed.
Tasks 2.1 through 2.3 have also been completed. Tasks under 4.0 Deliver and 5.0 Management
are ongoing and will carried out for the entire duration of the project with major deliverables
being associated with faculty presentations in fall and spring as well as competitions held during
SYTS495. Plans for SYST495 include completion of tasks remaining under 2.0 Design/Method
of Analysis and 3.0 Implement.
The project schedule was set for 34 weeks. The project schedule can be found in Figure
11: Project Schedule. Project task durations were estimated. Total hours worked were
estimated by setting hours per group member per week at 10, for a total of 50 hours projected
per week. These hours were allocated to tasks scheduled per week. Cost and schedule
performance indices were calculated and can be found in Figure 12: Cost and Schedule
Performance Index. The proposed, earned, and actual values for the project were also
calculated and can be found in Figure 13: Proposed, Earned, and Actual Values. As of
December 4, 2011, 14 weeks have been completed in the project schedule. The budgeted
hours through week 14 were 650 while actual hours completed was 651. A record of team
hours through week 14 of the project can be found in Figure 14: Team Timesheet.
26
Proposed Work for SYST495

Design and Code Simulation
o

Finalize emissions indices and vehicle specific factors for AIT inputs (WBS 2.3)
Test and Validate Simulation
o
Input data from Denver International and Seattle Tacoma Inventory Results to
AIT, compare output from AIT to actual (WBS 2.4, WBS 2.5)

Finalize Design of Experiment
o
Research European GHG goals, formulate suggestions for proposed US GHG
goals (WBS 3.3)

Run Simulation and Analyze Results
o
Apply AIT to Dulles Airport: Analyze output, compare with formulated goals (WBS
3.1, WBS 3.2)

Conduct Sensitivity Analysis (using Value Hierarchy) (WBS 3.4)

Define Final Design and Develop Recommendations (WBS 3.4)
27
Design of a
Carbon Neutral
Airport
2.0 Design /
Method of
Analysis
3.0
Implement
4.0 Deliver
1.1 Context
2.1 Research
3.1 Apply Tool
4.1 Preliminary
Project Plan
5.1 WBS
1.2 Stakeholder
Analysis
2.2 CONOPS
3.2Analyze
Results
4.2 Final Project
Plan
5.2 Budget
1.3 Problem
2.3 Develop Tool
3.3 Formulate
Goals/Limits
4.3Poster
5.3 Weekly
Activity Summary
1.4 Need
2.4 Analyze Tool
3.4 Develop
Mitigation
Strategies
4.4IEEE
Conference
Paper
5.4Timesheets
1.5 Scope
2.5 Enhance Tool
4.5 Presentations
5.5 360
Evaluation
1.0 Planning
1.6
Requirements
5.0
Management
4.6 Competitions
Figure 10: Work Breakdown Structure
28
Figure 11: Project Schedule
Cost and Schedule Performance Index
1.8
1.6
Index Value
1.4
1.2
1
0.8
0.6
0.4
0.2
0
1
3
5
7
9
11 13 15 17 19 21 23 25 27 29 31 33 35
Week
CPI
SPI
Baseline
Figure 12: Cost and Schedule Performance Index
Proposed, Earned, and Actual Values
1800
1600
1400
Hours
1200
1000
800
600
400
200
0
1
3
5
7
9
11 13 15 17 19 21 23 25 27 29 31 33 35
Week
Proposed Total
Actual Total
Earned Value
Figure 13: Proposed, Earned, and Actual Values
Figure 14: Team Timesheet
Bibliography
ARB Mission and Goals. (2009, December 8). Retrieved 2011, from California Environmental Protection
Agency Air Resources Board: http://www.arb.ca.gov/html/mission.htm
Airports Council International. (2009). Guidance Manual: Airport Greenhouse Gas Emissions
Mangement.
Associates, Rocondo &. (2005). Denver International Airport Emissions Inventory. Denver, CO.
Brian Kim, I. A. (2009). ACRP Report 11 Guidebook on Preparing Airport Greenhouse Gas Emissions
Inventories. Washington, DC: Transportation Research Board.
David Scharr, L. S. (2010). Analysis of Airport Stakeholders. Integrated Communications Navigation and
Surveillance Conference.
Dexinger. (2009). Dexinger. Retrieved from AIA Introduces 2030 Commitment Program to Reach Goal of
Carbon Neutral by 2030: http://www.dexigner.com/news/17758
Energy Information Administration. (2011). Voluntary Reporting of Greenhouse Gases Program.
Retrieved 2011, from Independent Statistics & Analysis U.S. Energy Information Administration:
http://www.eia.gov/oiaf/1605/coefficients.html
Enviro.aero. (2011). Aviation's Role in Climate Change. Retrieved 2011, from enviro.aero:
http://www.enviro.aero/aviationsroleinclimatechange.aspx
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Airports. Retrieved 2011, from Federal Avaition Administration:
http://www.faa.gov/airports/planning_capacity/passenger_allcargo_stats/passenger/index.cfm
?year=all
First Environment, Inc. . (2008). Westchester County Airport Air Emissions Inventory.
Intergovernmental Panel on Climate Change. (2007). 3.5.3.3 Cost-benefit Analysis, Damage Cost
Estimates and Socaial Costs of Carbon - AR4WGII Chapter 3: Issues Related to Mitigation in the
Long-Term Context. IPCC.
IPCC. (2004). Putting Aviation's Emissions in Context.
Massechusetts Exectuive Office of Environmental Affairs. (2009). Massechusetts Environmental Policy
Act (MEPA). Retrieved 2011, from The Official Website of the Executive Office of Energy and
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Metropolitan Washington Airports Authority. (2010). Total Operations, Passengers, Mail, & Freight
Activities. Washington, D.C.
Metropolitan Washington Airports Authority. (2011). Facts about Washington Dulles International
Airport. Retrieved 2011, from Metropolitain Washington Airports Authority:
http://mwaa.com/dulles/663.htm
Office of Environment and Energy. (2000). Consideration of Air Quality Impacts by Airplane Operations at
or Above 3,000 feet AGL. Washington, DC: US Department of Transportation, Federal Aviation
Administration.
Port of Seattle. (2008). Port of Seattle Seattle-Tacoma International Greenhouse Gas Emissions Inventory
2006. Seattle, WA.
Schaar, D. (2011). Introduction to Airport Finance.
STERN. (2007). Status of Kyoto Protocol Ratification.
The Climate Registry (TCR). (2008). General Reporting Protocol. Los Angeles, CA.
U.S. Department of State. (June 2010). U.S. Climate Action Report 2010. Washington, DC: Global
Publishing Services.
U.S. Environmental Protection Agency. (2011, April 20). Climate Change - Greenhouse Gas Emissions.
Retrieved 2011, from U.S. Environmental Protection Agency:
http://www.epa.gov/climagechange/emissions/index.html
33
Definitions and Acronyms
ACRP: Airport Cooperative Research Program
AIT: Airport Inventory Tool
Carbon Neutral: no net release of carbon dioxide to the atmosphere by balancing a measured
amount of carbon released with an equivalent amount offset relative to a baseline quantity
Climate Change: major changes in temperature, rainfall, snow, or wind patterns lasting for
decades or longer due to human-made and natural factors
Dispersion: process of air pollutants spreading over a wide area in the ambient atmosphere
DOE: Department of Energy
EIA: Energy Information Administration
EPA: USEPA, United States Environmental Protection Agency
FAA: Federal Aviation Administration
GAV: Ground Access Vehicle
GHG: greenhouse gas, a gas that traps heat in the atmosphere
GSE: Ground Support Equipment
ICAO: International Civil Aviation Organization
Inventory: accounting of the amount of GHGs emitted to or removed from the atmosphere over
a specific period of time
Kyoto Protocol: a protocol to the United Nations Framework Convention on Climate Change
(UNFCCC or FCCC), aimed at fighting global warming
MWAA: Metropolitan Washington Airports Authority, Dulles International Airport and Reagan
National Airport managers
NAAQS: National Ambient Air Quality Standards
34
Appendix A: Emissions Indices
Emissions Indices
km
mi
Fuel Type
(select)
gallons
Liters
MMBtu
Mcf
kilograms
unit
(select)
Aviation Gasoline
Biodiesel - B10
Biodiesel - B100
Biodiesel - B2
Biodiesel - B20
Biodiesel - B5
Coal (Commercial)
Coal (Cooking)
Coal (Electric)
Coal (other)
Crude Oil
Diesel
Diesel Fuel (No. 1 and No. 2)
Ethane
Ethanol - E10 (Gasohol)
Ethanol - E100
Ethanol - E85
Heavy Fuel Oil (No. 5, 6 fuel oil), Bunker Fuel
Isobutane
Jet A, JP-8
Jet Fuel, Kerosene
Kerosene
Liquified Natural Gas (LNG)
Liquified Petroleum Gas (LPG)
Methanol - M100
Methanol - M85
Middle Distillate Fuels
Motor Gasoline
Motor/Auto Gasoline
Municipal Solid Waste
Natural Gas
Natural Gas (average HHV - 1029 Btu/scf)
Natural Gas (HHV 1000-1026 Btu/scf)
Natural Gas (HHV 1025-1050 Btu/scf)
-
kg CO2
/ Gallon
kg CO2
/ Liter
kg CO2 /
MMBtu
kg CO2 /
Mcf
kg CO2 /
kg
8.32
9.13
0
9.94
8.12
9.64
0
0
0
0
10.29
10.15
10.15
4.14
8.02
0
1.34
11.8
6.45
9.57
9.57
9.76
4.46
5.79
4.11
4.83
10.15
8.91
8.81
0
0
0
0
31.5328
34.6027
0
37.6726
30.7748
36.5356
0
0
0
0
38.9991
38.4685
38.4685
15.6906
30.3958
0
5.0786
44.722
24.4455
36.2703
36.2703
36.9904
16.9034
21.9441
15.5769
18.3057
38.4685
33.7689
33.3899
0
0
0
0
0
69.19
66.35
0
71.8
59.44
69.76
95.35
83.73
95.52
93.98
74.54
73.15
73.15
59.59
66.3
0
14.79
78.8
65.07
70.88
70.88
72.31
0
0
63.62
65.56
73.15
71.26
0
41.7
53.06
54.01
52.91
53.06
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
9.57
0
0
0
3.16
35