Greenhouse Gas Emission Metrics

by Maria Fara — May 2016 — Stakeholders and investor groups’ increasing need for transparency and enhancement of their company credibility motivates many organizations to assess their impact on global climate, change to quantify their GHGs emissions and commit to their reduction.  Often this becomes a facility managers’ duty and they find themselves in the predicament of how to convince upper management that emission reductions can be achieved through the implementation of sustainable practices and that other benefits, such as reduction in operation costs will occur.  By taking a detailed approach and using industry standards to measure GHGs, the FM will be in a good position to approach upper management and build a business case for GHG reductions.

Greenhouse gases and global increasing concern

Carbon dioxide (CO2), Methane (CH4), Nitrous oxide (N2O), Fluorinated, Hydrofluorocarbons (HFCs) Perfluorocarbons (PCFs) and Sulfur Hexafluoride (SF) gases are called Greenhouse gases (GHGs) because they trap heat in the atmosphere and they have been the major cause for global warming.  Why should we care about greenhouse gases and work to reduce their emissions?  The presence of natural greenhouse gasses in the atmosphere is obviously useful for the fluctuation of the temperature on the Earth and therefore beneficiary for the life on Earth.  Although, what is of concern for scientists today is the fact that in the last 150 years release of these gases in the atmosphere has increased with the increase of human activities including: burning fossil fuels, solid waste, trees and wood products, transportation, livestock and other agricultural practices and by the decay of organic waste in municipal solid waste landfills.  The increase of these gasses corresponds to the raising of the temperature of the Earth surface including lands and ocean.  NASA just put out their April temperature results which has been listed as the warmest month ever recorded and this puts 2016 on a potential track to be the hottest year ever recorded.  Temperature changes lead to changes in weather patterns, increases sea level rise, increased severe weather and other areas that can affect building operations.

What to track

We often refer to GHG emissions related to an organization as the organization’s carbon footprint.  In order to assess the carbon footprint associated with a company’s consumption and operation, a facility manager needs to identify and quantify a number of metrics, understand how they are generated, and come up with practices that limit GHG emissions.  The GHG emissions inventory consists of several steps that should be followed in order to produce data that is an appropriate reflection of the company’s carbon footprint, and that can be used in the company’s decision making process.  The World Resources Institute/World Business Council for Sustainable Development (WRI/WBCSD) GHG Protocol, has set some principles that are very useful to companies in the tracking process of their GHG emissions.

According to those principles the GHGs inventory should account for all the GHGs emission sources and activities within the company.  Inventory methods should be consistent over the years and be able to compare the emission activities over time.  Lastly, but no less important, the GHGs inventory should be transparent and accurate, to enable management to make reasonable decisions based on facts.

Following the guidance of the GHG Protocol, emissions can be separated in to three types as follows:

  • Scope 1:  Direct GHG emissions are emissions from sources that are owned or controlled by the reporting entity.
  • Scope 2:  Indirect GHG emissions are emissions from consumption of purchased electricity, heat or steam.
  • Scope 3:  Other indirect GHG emissions: GHG emissions that result from sources not owned or controlled by the company but are a consequence of company activities (ex. employees business or commuting travel).

Scope 1 and 2 are the most commonly tracked by companies, while the decision to track Scope 3 is usually based on the industry sector.

Reporting is a two-phased activity.  During Phase I, boundaries, business units and key individuals are identified, summarized in a report, and combined in to an action plan that will be used as a go by for the data collection process.  The action plan should include the most time efficient methodologies to be used in the collection of the data, department and personnel to involve in the collection, and also how often the data should be tracked and reported within the company.  Phase II is the data collection phase, during which a baseline is identified, the data is collected and analyzed, gaps are identified, and a GHG reduction plan is created.

Both organizational and operational company boundaries need to be established to delineate the types of operations and emission sources that have to be included in the inventory.  Identifying the boundaries identifies all the facilities associated with the organization based on the types of existing source and expected emissions, and a responsible person to be in charge of the data collection at each facility.  During this phase, it is also important to create a process to identify new facilities or new emission sources within existing facilities.  Phase I is also the time to choose which standardized protocol to use.  All protocols adopt the same approach in using electronic excel spreadsheets to conduct the necessary emission calculations.  The most known protocols are the following:

  • The GHG Protocol, A Corporate Accounting and Reporting Standard (Revised Edition), World Business Council for Sustainable Development and World Resources Institute, 2004.
  • California Climate Action Registry General Reporting Protocol, Version 2.2, California Climate Action Registry, April 2007.
  • U.S. EPA Climate Leaders GHG Inventory Protocol, Core Module Guidance, October 2004.

Companies should be consistent with which protocol is used to keep the data comparable.  The next step is creating a baseline to use as a reference point to compare the GHGs emission collection overtime.  General rule of thumb is that a company can use any year after 1990 as a baseline.  If a company is starting their process in 2008 the 2007 data can be used as a baseline.  The baseline shouldn’t change from year to year, but can be adjusted to reflect structural changes within the organization.

Data collection can be time consuming.  In order to collect data for all the major emissions sources for the six major GHGs, all the activities conducted by the company need to be taken in consideration.  It is important to follow the requirements laid out in the action plan and make sure that all the people involved in the collection do their part within the established time.  Collection involves the participation of management and often of the accounting department, and on a time defined basis the whole workforce is required to participate into surveys.   The tool used for the collection should best fit the collection needs and the people involved in the collection should be familiar with the tool.  Users should pay close attention to the units in which the data should be collected which should match the calculator requirements.  As said above, tools are usually excel spreadsheets that have built in calculators capable of providing you with the emissions value totals.  Typical tools have the capability to collect information within the three scopes, and divide them into direct and indirect sources.  After all the sources of emission have been identified within each facility, data collection should be separated into 3 parts:

  • Facility Data: utilities bills showing kWh purchased electricity, onsite fuel usage and facility refrigeration usage.
  • Business Travel Data: numbers of trips, miles per trip, mode of transportation, and type and amount of fuel.
  • Fuel Data:  numbers of trips, miles per trip, mode of transportation, weight transported, and type and amount of fuel.

The data collected should be gathered into a single database and gaps should be identified and analyzed to see how they can affect the outcome of the analysis.  When data is not available, it should be either estimated based on other data received or a default value should be used.  Data should be reviewed and analyzed, facilities should be compared among each other to identify outliers, and the energy usage should be checked for seasonal trends.  Data that seems like an outlier from the normal trend, it should be checked for verification.  Final emissions data obtained by the calculation tool should be compared to the baseline and analyzed to understand where improvements can be made to reduce emissions.

Choosing the right Tools:

When choosing the right tool to support the calculation of the GHGs emissions there are two important things to keep in mind: it should be able to collect information for all of the major GHGs gases, and it should give you the freedom to add/remove facilities in case of an organizational change.  The Climate Leaders Simplified GHG Emission Calculator (SGEC) is the tool made available by EPA for small business and low emitters to help them to manage their emissions and to report it following the Climate Leaders Greenhouse Gas Inventory Protocol guidance.  Energy management tools are also good resource for the GHGs collection, an example is ENERGY STAR Portfolio Manager which allows organization to track and assess energy consumption across its entire portfolio of buildings.  The tool also tells you the GHGs associated with the energy consumption of the building.  The information collected into Portfolio Manager can be easily downloaded as an Energy Performance Report for all the facility within the company and then imported into the GHGs calculator tool.


There are several reasons why facility managers should work on lowering their carbon footprint, considering the energy used in buildings accounts for roughly one quarter of worldwide emissions of GHGs.   There are also economic reasons, in fact energy costs are rising, and facility managers need to understand that there are several measures that can be implemented to make a facility more energy efficient, reduce its carbon footprint, and have a positive payback.  Saving energy also helps the environment by reducing use of fossil fuels, decreasing greenhouse gas emissions associated with business operation and helps to show sustainable commitment to company’s stakeholders and investor groups.  These are all valid points a facility managers can use when developing a business case for reducing the carbon footprint of their facility.

While starting to track the GHG emissions for their company the facility managers should have good knowledge of the company boundaries and what type of emissions are produced by the company’s activities.  Important step is to construct a strong action plan that includes a baseline and rigorous data validation and verification procedures, and that incorporate the use of a strong combination of a good calculator and database that can be used to analyze the data and provide future reduction initiatives that are relevant to the organization business needs.

Maria FaraMaria Fara, Sustainability Facility Professional and LEED Accredited Professional, is a Project Manager at Facility Engineering Associates.  During her 15 years of experience she has worked on and managed numerous projects of varying sizes in the areas of sustainability assessments, energy management, and environmental consulting projects such as Phase I and Phase II environmental site investigations and Spill Prevention Control & Countermeasure (SPCC) plans, workforce development and Leadership in Energy and Environmental Design Certification (LEED®) Certification.

Facility Engineering Associates, P.C. (FEA)  is an engineering and facility management consulting firm supporting owners and managers of existing facilities. FEA was founded in 1992 on the principle that there is a better way to manage the built environment by balancing the challenges of providing a safe, secure, and healthy environment; maintaining an aging infrastructure; and improving how the FM organization operates. We help our clients improve the way they manage, operate, maintain, and fund the built environment to enable facilities that are safer, healthier, resilient, productive and cost-effective.

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