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

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an environmental treaty with the goal of reducing climate change through the stabilization of

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 Byrd-

Hagel 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

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Environmental Policy Act (MEPA), and Washington State’s Environmental Policy Act (SEPA).

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 non-

stationary 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

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of this project will be Washington Dulles International Airport (IAD) of the Metropolitan

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.

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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)

Figure 2: Stakeholder Interaction Diagram

Airport Stakeholder Interactions Model Overview:

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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

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

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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

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 non-

stationary 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.

83.0%

10.3%4.5%

2.2%

2009 Greenhouse Gas Emissions by Gas(percentages based on CO2 equivalent)

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.  

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Figure 8: Airport Inventory Tool

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

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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

f i∗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.  

Equation 2: Emissions = ∑j

f j∗Ej + ∑k

f k∗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

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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

f m∗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

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.

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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.

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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

neutrality.

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.

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Reduce energy need

Maximize energy efficiency

Renewable Energy

Offs et

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

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.

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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

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

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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

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

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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.

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.

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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.

27

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)

28

Figure 10: Work Breakdown Structure

29

Design of a Carbon Neutral

Airport

1.0 Planning

1.1 Context

1.2 Stakeholder Analysis

1.3 Problem

1.4 Need

1.5 Scope

1.6 Requirements

2.0 Design / Method of

Analysis

2.1 Research

2.2 CONOPS

2.3 Develop Tool

2.4 Analyze Tool

2.5 Enhance Tool

3.0 Implement

3.1 Apply Tool

3.2Analyze Results

3.3 Formulate Goals/Limits

3.4 Develop Mitigation Strategies

4.0 Deliver

4.1 Preliminary Project Plan

4.2 Final Project Plan

4.3Poster

4.4IEEE Conference

Paper

4.5 Presentations

4.6 Competitions

5.0 Management

5.1 WBS

5.2 Budget

5.3 Weekly Activity Summary

5.4Timesheets

5.5 360 Evaluation

Figure 11: Project Schedule

1 3 5 7 9 11 130

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

Cost and Schedule Performance Index

CPI SPI Baseline

Week

Inde

x Va

lue

Figure 12: Cost and Schedule Performance Index

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 350

200

400

600

800

1000

1200

1400

1600

1800

Proposed, Earned, and Actual Values

Proposed Total Actual Total Earned Value

Week

Hour

s

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

Federal Aviation Administration. (2011). Passenger Boarding (Enplanement) and All-Cargo Data for U.S. 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 Environmental Affairs: http://www.env.state.ma.us/mepa/

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

34

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

35

Appendix A: Emissions Indices

Emissions Indices

km mi

Fuel Type (select) gallons Liters MMBtu Mcf kilograms

unit - kg CO2 / Gallon

kg CO2 / Liter

kg CO2 / MMBtu

kg CO2 / Mcf

kg CO2 / kg

(select)

Aviation Gasoline 8.32 31.5328 69.19 0 Biodiesel - B10 9.13 34.6027 66.35 0 Biodiesel - B100 0 0 0 0 Biodiesel - B2 9.94 37.6726 71.8 0 Biodiesel - B20 8.12 30.7748 59.44 0 Biodiesel - B5 9.64 36.5356 69.76 0 Coal (Commercial) 0 0 95.35 0 Coal (Cooking) 0 0 83.73 0 Coal (Electric) 0 0 95.52 0 Coal (other) 0 0 93.98 0 Crude Oil 10.29 38.9991 74.54 0 Diesel 10.15 38.4685 73.15 0 Diesel Fuel (No. 1 and No. 2) 10.15 38.4685 73.15 0 Ethane 4.14 15.6906 59.59 0 Ethanol - E10 (Gasohol) 8.02 30.3958 66.3 0 Ethanol - E100 0 0 0 0 Ethanol - E85 1.34 5.0786 14.79 0 Heavy Fuel Oil (No. 5, 6 fuel oil), Bunker Fuel 11.8 44.722 78.8 0 Isobutane 6.45 24.4455 65.07 0 Jet A, JP-8 9.57 36.2703 70.88 0 3.16 Jet Fuel, Kerosene 9.57 36.2703 70.88 0 Kerosene 9.76 36.9904 72.31 0 Liquified Natural Gas (LNG) 4.46 16.9034 0 0 Liquified Petroleum Gas (LPG) 5.79 21.9441 0 0 Methanol - M100 4.11 15.5769 63.62 0 Methanol - M85 4.83 18.3057 65.56 0 Middle Distillate Fuels 10.15 38.4685 73.15 0 Motor Gasoline 8.91 33.7689 71.26 0 Motor/Auto Gasoline 8.81 33.3899 0 0 Municipal Solid Waste 0 0 41.7 0 Natural Gas 0 53.06 9.57 Natural Gas (average HHV - 1029 Btu/scf) 0 0 54.01 0 Natural Gas (HHV 1000-1026 Btu/scf) 0 0 52.91 0 Natural Gas (HHV 1025-1050 Btu/scf) 0 0 53.06 0

36