How to Calculate Your Carbon Footprint

Are you keeping track of your building’s environmental impact yet?

If you’re not already mandated to do so, chances are that day isn’t too far into the future, especially as state governments begin to impose restrictions and shareholders expect deeper management considerations of environmental risk.

Companies such as Chevrolet, Intel, Nike, Coca-Cola, and Microsoft are all working to reduce their greenhouse gas emissions. Make calculating your carbon footprint easy by following these three steps.

1) Pick a Measurement Method
Much like building certification programs, there are multiple standards for greenhouse gas (GHG) reporting – it’s up to you to determine which one to use.

You might consider the Greenhouse Gas Protocol from World Resources Institute (WRI) and the World Business Council for Sustainable Development (WBCSD), which accommodates complex or multinational organizations.

There are also state versions that include mandatory reporting, such as those required for large emitters by Oregon’s Department of Environmental Quality or California’s Air Resources Board. These protocols offer standardization and technical guidance to facility managers.

If you want to go a simpler route, start by creating a ballpark assessment of your emissions.

The bulk of a building’s footprint is energy use, including electricity, natural gas, and other sources tied to fossil fuel.Review your utility bills and conduct some basic calculations to reveal a large portion of these impacts.

For example, if a building consumes 500 therms of natural gas, multiply by a factor of 11.7 to get the pounds of carbon dioxide emissions: 500 x 11.7 = 5,580 pounds of CO2 from natural gas use.

The same is true for electricity use, where the number of kilowatt-hours consumed over a period is multiplied by the current emissions intensity of your specific grid region (available online through the EPA).PageBreak

2) Select an Emissions Scope
No matter which formula you use, you also need to identify your emissions scope. This sets an accounting boundary for what to include within your data collection and categorizes the measurement of impacts.

The Greenhouse Gas Protocol classifies emissions into one of three scopes, largely based on proximity and control over emissions:

• Scope 1 offers the highest degree of control, such as burning coal or gas on-site and releasing emissions through a smokestack. The emitter owns the source and has complete control over whether or not the fuel is burned and creates emissions.
• Scope 2 encompasses grid electricity or off-site heating/cooling sources, including purchased electricity, steam, or chilled water. Users can control the amount of energy consumed, but they do not control how the energy is produced or its emissions intensity.
• Scope 3 accounts for emissions with the least control or ownership. Examples include employee travel and commuting, vendor supply chain, or embedded energy in building products.

Scopes are useful for categorization, but beware of “scope-a-dope,” where attempting to track and categorize every last activity becomes overwhelming and leads to inaction.

Instead, start by focusing on major areas of concern. There’s no required way to set boundaries, so do what best fits your organization.

For instance, many companies that have been tracking GHG impacts for years do not yet consider Scope 3.

No matter the method, the key is consistency and transparency. Tracking data over time and following an established routine can help identify areas for improvement and show results from actions taken.

3) Ask for Help
If you don’t have time to calculate your carbon footprint, there are a number of organizations that can help. These include private consultants, non-governmental organizations, and the EPA.

Some accounting and auditing firms also offer calculation services as investors may consider GHG emissions a risk factor.

You can also use a number of online and software solutions. There are basic carbon calculators such as the one provided by the Nature Conservancy (see sidebar at left).

A growing number of building automation systems are being harnessed to track GHG emission performance, resulting in a valuable interface with your energy management platform.

Capitalize on the Data
Tracking GHG emissions can prepare your organization for potential future compliance and inquiries from investors, stakeholders, or building occupants.

More importantly, it allows building operators to track overall building performance related to energy and sustainability. Acting on this data will lead to improved efficiency, cost savings, and higher levels of occupant satisfaction.

Patrick Nye has over a decade of experience in carbon and clean energy. He leads Consulting Services for the Bonneville Environmental Foundation. He can be reached at (503) 709-3975 or [email protected].