1. Mieko A. Ozeki
Tracking Greenhouse Gas Emissions on College Campuses in the U.S.
The Methods and Application of the Greenhouse Gas Inventory in Climate Action Planning
Courtesy of the University of Vermont (Sally McKay)
Mieko A. Ozeki
ALM Sustainability and Environmental Management candidate
Prepared for ENVR E-130 Global Climate Change
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Table of Contents
THE GREEN UNIVERSITY: MEASURING BEYOND THE TRENDS ............................................. 2
BACKGROUND ...................................................................................................................................... 2
The Talloires Declaration (1990) .................................................................................................... 2
American Colleges & University Presidents Climate Commitment (2007) ..................................... 3
GREENHOUSE GAS INVENTORY ........................................................................................................ 4
THE PROCESS FOR GREENHOUSE GAS EMISSION REPORTING ............................................. 4
STEP 1: DATA COLLECTION ................................................................................................................. 5
Emission Source Types .................................................................................................................... 5
STEP 2: CALCULATING GHG EMISSIONS ............................................................................................. 5
The IPCC Guidelines for Developing a Greenhouse Gas Inventory ............................................... 5
Protocols and Calculators for Estimating GHG Emissions on College Campuses ........................ 6
STEP 3: REPORTING GHG EMISSIONS .................................................................................................. 7
CONCLUSION ........................................................................................................................................... 8
FIGURES & TABLES ................................................................................................................................ 9
FIGURE 1: A SUMMARY OF SCOPE EMISSIONS..................................................................................... 9
TABLE 1: GREENHOUSE GASES COVERED IN THE IPCC’S 2006 GUIDELINES ....................................... 9
FIGURE 2: MAIN CATEGORIES OF EMISSIONS BY SOURCES AND REMOVALS BY SINKS. ..................... 10
WORKS CITED........................................................................................................................................ 11
Acknowledgements
I would like to thank Gioia Thompson, Director of the Office of Sustainability at the University
of Vermont, who provided me with the resources on tracking environmental progress and
greenhouse gas emissions.
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The Green University: Measuring Beyond the Trends
During the past two years, a number of publications have issued “green college” rankings. Based on
college sustainability coordinators’ responses to questionnaires, Sierra Magazine released its own “Cool
Schools” rankings, including a top 10 green schools list, in September 2008; while the Sustainable
Endowments Institute issued its first College Sustainability Report Card in the same year, giving letter
grades to different colleges for their sustainability performance; and recently Princeton Review
published its Green Rating as part of its college ranking system in May 2009 and highlighting schools in
its Honor Roll. These green rankings are an indicator of a growing interest in what institutions of higher
education are doing to reduce its contribution to global climate change, and how they educate future
generations of leaders to take on the economic, social, and environmental challenges of climate change.
The intent of this paper is to look beyond the trendiness of “green colleges,” and focus on the
commitments that institutions of higher education have made to reduce its greenhouse gas emissions.
Most colleges and universities campuses are like cities because they manage their own infrastructure
and operations within the cultural context of academia. The methodology behind greenhouse gas
inventories will be discussed within the context of how colleges use this tool to systematically collect
and report on their GHG emissions. Institutions use this tool to establish a baseline on their GHG
emissions and track the institution’s progress toward emissions reductions.
Different greenhouse gas inventory protocols and calculators will be discussed to understand how
GHG emissions are calculated because there is no standard inventory method. Colleges and
universities, who have made climate commitments, use different inventory protocols and calculators to
estimate their emissions. The ACUPCC recommends that its signatories use the Clean Air Cool Planet
Campus Calculator, but does not preclude people from using other calculators or customizing their own
calculators.
Background
“Green college” rankings scratch the surface of an evolving sustainability movement on college
campuses in North America and other countries. In alignment with the Civil Rights and social
movements of the Sixties and the momentum of environmental movement in the 1970s, colleges and
universities took on initiatives to reduce their impacts on the environment. The energy crisis of the
1970s motivated many colleges and universities to take aggressive action toward increasing energy
efficiency on their campuses, particularly to reduce their operational costs (Creighton, 1998).
Over the next thirty years, the major drivers for most colleges were to reform campus operations
(including facilities and energy management) and integrate sustainability into academia’s paradigm as
the economic, social, and environmental pressures of climate change come to the forefront. Grassroots
activism on college campuses, involving students, faculty, staff, have had some impact on policy and
operational changes on college campuses. Some college administrators and presidents took heed of
demands to reduce their institution’s contributions to climate change. They done this by making policy
changes within their institutions and later reinforcing their commitments to climate neutrality by holding
themselves accountable to peer institutions. One of the first commitments to sustainability in higher
education was the Tailloires Declaration in 1990; and over a decade later followed up with the American
College & University Presidents Climate Commitment in 2007.
The Talloires Declaration (1990)
The Talloires Declaration was the first official statement made by university administrators of a
commitment to environmental sustainability in higher education. The declaration was composed in
1990 prior to the 1992 Earth Summit in Rio de Janeiro and after the publication of the Brundtland
Commission’s “Our Common Future” in 1987. It was composed at an international conference, hosted
by Tufts University at its European Center in Talloires, France, on “The Role of Universities in
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Environmental Management and Sustainable Development” (Association of the University Leaders for a
Sustainable Future, 2008). The declaration included a concise introduction on the urgent need for
higher education to take a lead in sustainability, and provided a ten-point action plan for integrating
environmental literacy and sustainability into university teaching and practice. At the end of the
conference, twenty-two college presidents and chancellors from the U.S. and other countries signed the
declaration and within a year after the conference, 125 presidents had signed onto this declaration. Tufts
University hosted and supported signatories of the Talloires Declaration for a couple years when the
Secretariat of University Presidents for a Sustainable Future was inaugurated in 1992. Over the next
decade, the Secretariat became the Association of University Leaders for a Sustainable Future (ULSF)
and moved to Washington, D.C. where it still supports Talloires signatories.
The Talloires Declaration stimulated institutions to address sustainability in academia and furthered
initiatives to operationalize environmental sustainability within the institutions infrastructure. Some
institutions in the U.S. began to pioneer environmental initiatives, addressing the “low hanging” fruit on
their campuses such as recycling programs and implementing energy efficiency technologies, in the
1990s. As more institutions got involved in incorporating environmentally sustainable practices, the
added pressure of climate change brought on a new push for institutions to address greenhouse gas
emissions.
American Colleges & University Presidents Climate Commitment (2007)
When the United States decided to not ratify the Kyoto Protocol in 1997, several states and local
governments took up the ambitious commitments to reduce greenhouse gases in the absence of national
leadership (Rappaport & Hammond, 2007). Colleges and universities followed suit toward making
reductions in their heat-trapping emissions by receiving and giving their support to regional, state, and
local efforts. A group of twelve college presidents, who attended the Association for the Advancement
of Sustainability in Higher Education (AASHE) Conference in October 2006 at Arizona State
University, agreed to become Founding Members of Leadership Circle to develop a new commitment
for institutions in higher education to address climate change (AASHE, 2007). Two months after the
conference, the Founding Members sent out nearly 400 letters to peer institutions and invited them to
join this initiative. The resulting document was the American Colleges & University Presidents Climate
Commitment (ACUPCC), which launched on March 31, 2007. During the first year of the ACUPCC,
152 presidents and chancellors became charter signatories in 2007 and as of May 2009, there are 633
signatories from colleges and universities in the U.S., Canada, Hungary, and the Republic of Palau
(AASHE, 2007). Ninety-five presidents agreed to be part of the Leadership Circle to promote this
initiative with their peers and be representatives address the press on this commitment.
Signatories of the ACUPCC recognize the scientific consensus on global warming, which is largely
caused by humans, and that action needs to be taken by colleges and universities to address climate
change because of their role in society. Similar to the Talloires Declaration, it recognizes that colleges
and universities can exercise their ability to lead in their communities and throughout society by
reducing greenhouse gas emissions on their campuses, and by educating graduates to achieve climate
neutrality through the integration of sustainability in their curriculum. Although there may be shortterm challenges, they believe that the long-term economic, health, social, and environmental benefits
outweigh these challenges. ACUPCC signatories are required to take the following actions to reduce
greenhouse gas emissions and achieve climate neutrality (AASHE, 2007):
(1) create institutional structures to guide the implementation of a climate action plan (such as an
office of sustainability) within two months of signing the document;
(2) complete a comprehensive all greenhouse gas inventory (including emissions from electricity,
heating, cooling, transportation, and air travel) within one year of signing the document, and
update the report on an annual basis;
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(3) create an institutional action plan toward climate neutrality (also called climate action plan)
within two years of signing the document.
These requirements are the long-term components of the commitment and in the short-term,
institutions are also required to initiate two or more tangible actions to reduce greenhouse gas emissions.
Tangible actions include establishing a green building policy for all new campus buildings, developing a
transportation demand management system, and adopting an energy efficiency appliance purchasing
policy. The third component of the ACUPCC is that signatories are required to make their climate
action plans, GHG inventories, and progress reports publicly available by providing this material to
AASHE to post and disseminate the information (AASHE, 2007).
ACUPCC signatory institutions represent less than 15% of all colleges and universities in the United
States. Although the ACUPCC has drawn in several hundred institutions to sign and accept these
requirements, many other institutions have launched their own institutional climate commitments.
Institutions, such as Harvard University and Yale University, decided not to sign the ACUPCC have
made their own climate neutrality or reduction goals. The actions taken by ACUPCC signatories and
non-ACUPCC institutions are very similar, particularly tracking their GHG emissions, and then
developing and implementing their climate action plans.
Greenhouse Gas Inventory
A greenhouse gas inventory accounts for the amount of greenhouse gases emitted to or removed from
the atmosphere during a specific time period (U.S. Environmental Protection Agency, 2009). It
provides information on activities that cause and reduce emissions as well as a background on the
methodology used to collect and calculate the data. At an institutional level, a GHG inventory is an
accounting of all greenhouse gases generated by an organization; and typically consists of the emissions
generated from energy production, transportation, as well as animal and food waste (Rappaport &
Hammond, 2007). The difference between GHG inventories and an ecological footprint is that an
ecological footprinting measures the amount of biologically productive water and land area required to
support the demands of a population or productive activity (Kitzes & Wackernagel, 2009). It is used as
an environmental indicator of biological resource depletion caused by human activity and increasing
global human population. It does not fully account for climatic changes that occur due to increases in
heat-trapping gases.
Inventories are needed by policymakers to track emission trends and develop strategies and policies
to assess progress. Scientists use GHG inventories as inputs to economic and atmospheric models. In
the case of colleges and universities, the GHG inventory is needed to establish a baseline and provides a
benchmark against which improvements can be quantified (Rappaport & Hammond, 2007). A GHG
inventory is not a precise measure of all emissions associated with an institution, but is a comprehensive
measure of an institution’s overall contribution to global climate change. It is difficult to track all of the
sources of campus emissions using air-monitoring equipment, and is much more manageable to collect
usage data (i.e. utility bills, mileage logs) and calculate the emission equivalents.
The Process for Greenhouse Gas Emission Reporting
The greenhouse gas inventory process has three main components: data collection, emissions
calculation, and reporting. Documentation of this process is key because inventories are largely
customized to fit the defined boundaries of an institution or geographical area (city, town, state,
regional, or national) within a specified period of time. The ACUPCC recommends, in the Greenhouse
Gas Inventory Brief (2007), that GHG analysts keep a journal of the process and source of data,
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including the people contacted for data. It also is important to identify and record the correct data
sources into a legacy document, which will help with the facilitation of future inventory processes.
Step 1: Data Collection
The raw data for a campus GHG inventory calculation generally falls under the following categories:
 purchased electricity
 agriculture
 purchased steam/chilled water
 solid waste (incinerated and landfill)
 on-campus stationary sources
 refrigerants and other chemicals
(energy generation)
 Offsets (or Renewable Energy Credits etc.
 transportation
This data can be typically acquired from a variety of sources at the institution, including the physical
plant or facilities department, campus planning office, local utilities provider, etc. The above data
categories can be grouped into emission source types, called scope emissions, based on the way they are
emitted from the source.
Emission Source Types
There are three different emission scopes (Figure 1) that deal with the release of dangerous
greenhouse gases be it intentional or unintentional. Scope 1 are emissions that occur directly from a
source. These emissions occur because of activities owned wholly or in part by an institution, and
include emissions from the combustion of fossil fuels for heating buildings, heating hot water, and
powering the vehicle fleet used for on-site transportation of faculty, staff, and students. Scope 2 are the
indirect greenhouse gas emissions released from sources that are not owned by the institution, but occur
because of an institution’s activities. This type of emission category includes: electricity purchased
from third party-providers.
The final category, Scope 3, are also indirect emissions, but are more difficult to track because thirdparty data needs to be collected from multiple sources that may or may not be easily identified. This
category includes emissions resulting from students and staff commuting to and from the college
campus, from deliveries, from university-related travel on trains, buses, and aircraft. Other indirect
emissions in this category are the construction or renovation of buildings, and all materials purchased
and used by the institution. The life cycle emissions of a product are helpful for an institution to
understand the impacts associated with the production, transport, and final disposal (reuse, recycle, or
dump) of goods and waste products.
Step 2: Calculating GHG Emissions
Once the raw data is collected, the next step is to calculate the institution’s GHG emissions, using an
emissions calculator. There are multiple GHG calculator tools available, especially for college
campuses, to tabulate the emissions of an institution. Each carbon calculator provides procedural
protocols for investigating campus GHG emissions. These protocols differ from one another, but are
based on a framework developed by the Intergovernmental Panel on Climate Change.
The IPCC Guidelines for Developing a Greenhouse Gas Inventory
In 2006, the IPCC released its Guidelines for National Greenhouse Gas Inventories, which were
produced at the invitation of the United Nations Framework Convention on Climate Change
(UNFCCC). The 2006 Guidelines were an update to Revised 1996 Guidelines and provides
internationally agreed methodologies for estimating a country’s GHG emissions. This guideline is part
of a series of workbooks produced by the IPCC, and are used to develop protocols and tools for
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7. Mieko A. Ozeki
calculating GHG emissions. The key concepts behind greenhouse gas inventories are that
anthropogenic emissions and removals are a result of human activity (Eggleston, Buendia, Miwa, Ngara,
& Tanabe, 2006). The differences between anthropogenic emissions and removals with natural
emissions are that emissions and removals on managed land (i.e. agriculture, forestry, and other land
uses) are taken as a proxy to human activity, and natural inter-annual variations in emissions and
removals are assumed to work itself out over time. Another concept is that inventories account for
emissions within a national territory, or in the case of college campuses, within a defined institutional
boundary.
In addition, GHG inventories contain estimates of emissions and removals within a calendar year
during which the gases are emitted or removed from the atmosphere. A sequence of annual GHG
inventory estimates are collected as a time series (i.e. 1990 to 2000) such that emissions can be tracked
over time; and it is understood that appropriate estimates should be made when past data is not
available. The final key concept is that a GHG inventory report includes a standard set of reporting
tables that cover all the gases and years; and a written report is prepared on the methodologies and data
used to prepare the inventory.
The 2006 Guidelines cover a list of greenhouse gases (Table 1) that should be calculated and
reported in the inventory because of their Global Warming Potential (GWP). GWP is a measure of how
much a given mass of gases contribute to global warming, or the radiative forcing of a ton of greenhouse
gases over a given time period, i.e. 100 years, to a ton of carbon dioxide (CO2) (Eggleston, Buendia,
Miwa, Ngara, & Tanabe, 2006). The IPCC provides information on other gases (see Table 1) that were
pre-cursor gases reported in GHG inventories. Estimates of GHG emissions and removals are separated
into sectors, which are groupings of related processes, sinks, and sources (Figure 2).
The most common and simple methodological approach is to combine the information on the extent
to which human activity takes place (called activity data) and multiply it by an emissions factor
(Rappaport & Hammond, 2007). The simple calculation appears as the following:
Emissions = The sum of (Activities x Emission factors)
Activities are commonly measured as the quantity of commodity purchased (i.e. therms or cubic
meters of natural gas burned, gallons of heating oil, or kilowatt hours of electricity generated or
purchased). The emissions factor is a coefficient that quantifies the emissions or removals per unit of
activity.
Protocols and Calculators for Estimating GHG Emissions on College Campuses
The IPCC guidelines provide the main principles on conducting and reporting a GHG inventory for
nations, but these guiding principles can be applied at an institutional level. There are a number of
protocols available to institutions in higher education, which layout the procedures for collecting,
calculating, and reporting GHG emissions. The emissions calculators that colleges and universities use
to calculate their GHG emissions are largely based on a specific protocol or customized to fit different
protocols. The following calculator tools are the most commonly used by colleges and universities in
calculating their GHG emissions:
Clean Air Cool Planet Campus Carbon Calculator
The ACUPCC recommends signatories to use the Clean Air Cool Planet Campus Carbon Calculator
to calculate GHG emissions on campus, even though the reporting framework of the Commitment is
compatible with other calculators. The calculator is a Microsoft Excel-based spreadsheet tool with
built-in formulas, conversions, and emissions factors (ACUPCC, 2007). Data analysts, proficient in
Excel, can alter formulas and emission factors to fit their institutions. This calculator adapts the IPCC
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framework and the methodologies and calculators of the Greenhouse Gas Protocol Initiative for higher
education institutional use.
The GHG Protocol Initiative is a partnership of the World Resources Institute and the World
Business Council for Sustainable Development. They work with businesses, governments, and
environmental groups to address climate change by building credible and effective programs.The
protocol consists of two modules and an inventory calculator. The modules are Corporate Account and
Reporting Standard, which is the method for organizations to inventory and report GHG emissions, and
Project Accounting, which are the guidelines for calculating reductions in emissions from specific
projects. The Clean Air Cool Planet calculator includes major scope emissions including on-campus
energy production, purchased electricity, transportation, agriculture, refrigerants, and waste.
GHG Protocol Inventory Calculator
The GHG Protocol Inventory Calculator is a widely used international accounting tool for
governments and businesses. It is argued to be an emerging common standard used in the business
context. The GHG Inventory Calculators are a series of tools, mostly Excel spreadsheets with
accompanying step-by-step guides that measure individual elements of emissions sources such as CO 2
emissions from transportation or mobile sources. These calculators are available to industry
(manufacturers), office-based and service-based sectors as toolsets with each calculator customized to a
specific industry.
The Greenhouse Gas Protocol: Designing a Custom GHG Calculator
The GHG Protocol Initiative also offers a guidebook for customizing an existing GHG Protocol
calculation tool to fit a specific emissions reduction program or to closely reflect what is happening on a
national, regional, and institutional level. Harvard University currently uses WRI’s GHG Protocol as
well as the Climate Registry’s General Reporting Protocol to develop their own customized greenhouse
gas calculator (Martin, 2008)
Climate Action Registry Reporting Online Tool (CARROT)
The Climate Action Registry Reporting Online Tool (CARROT) is an emissions calculator and
reporting tool that correlates with the California Climate Action Registry General Reporting and
Certification Protocols. This web-based spreadsheet tool is consistent with the GHG Protocol Initiative,
and has four main functions: it helps Registry participants to calculate and report GHG emissions;
facilitates certification; permits the public to view aggregated reports; and enables data tracking.
CARROT aligns with the ACUPCC standardized reporting framework and is accessible only to Registry
participants from California. ACUPCC recommends Californian signatories to use CARROT if they
wish to report to the Registry (ACUPCC, 2007).
Step 3: Reporting GHG Emissions
Colleges and universities generally report their greenhouse gas emissions by including a summary of
the calculated emissions and a narrative report of the outcomes. The reports provide documentation on
how the data was collected, the physical boundary (i.e. project, building, campus), time frame, and the
specific activities that the data team elected to include (Rappaport & Hammond, 2007). It also specifies
the protocol and calculator tools used to tabulate the emissions data. Most organizations, including the
IPCC, recommend third-party verification of the data to ensure quality of the data reported by the
institution.
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Conclusion
Over the last thirty years, colleges and universities have been part of social change movements due
to student activism taking place on their campuses. As the pressures and challenges of climate change
mount, institutions of higher education are beginning to see their role in reducing their contributions to
global warming both on an operational and academic level. Climate commitments, such as the
ACUPCC or college president’s declaration for climate neutrality, are a testament to institutional change
within the context of a global problem.
Greenhouse gas inventories is an excellent comprehensive tool to understand an institution’s
contributions to global warming and identify the opportunities for GHG emissions mitigation. Although
there isn’t a specific GHG inventory standard for colleges and universities to use, this tool is an
informative process for these institutions to take action. By making data and narrative reports available
to the public via the Internet, colleges and universities are held accountable for their actions and the
policies implemented on their campuses. Global calculators summarize the emissions totals in CO2
equivalents, and are used to determine the largest sources of global warming pollutants. The GHG
inventory, combined with financial analysis, helps guide the development of a climate action plan for
the long-term viability and sustainability of the institution.
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Figures & Tables
Figure 1: A Summary of Scope Emissions
Source: Clean Air Cool Planet at http://www.cleanair-coolplanet.org/.
Table 1: Greenhouse gases covered in the IPCC’s 2006 Guidelines
(Source: Eggleston, Buendia, Miwa, Ngara, & Tanabe, 2006)
Greenhouse gases:
o carbon dioxide (CO2)
o methane (CH4)
o nitrous oxide (N2O)
o hydrofluorocarbons (HFCs)
o perfluorocarbons (PFCs)
o sulphur hexafluoride (SF6)
o nitrogen trifluoride (NF3)
o trifluoromethyl sulphur pentafluoride (SF5CF3)
o halogenated ethers (e.g., C4F9OC2H5, CHF2OCF2OC2F4OCHF2, CHF2OCF2OCHF2 )
o Other halocarbons not covered by the Montreal Protocol including CF3I, CH2Br2, CHCl3,
CH3Cl, CH2Cl2
Other Gases or Pre-Cursors:
o Nitrogen oxides (NOx),
o Ammonia (NH3),
o Carbon monoxide (CO)
o Non-methane volatile
organiccompounds (NMVOC),
o Sulphur dioxide (SO2)
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Figure 2: Main categories of emissions by sources and removals by sinks.
Source: 2006 IPCC Guidelines for National Greenhouse Gas Inventories: General Guidance and Reporting
(Eggleston, Buendia, Miwa, Ngara, & Tanabe)
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