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Carbon & Emissions Offsetting - TheGreenOffice.com

The Office Footprint Calculator™ was developed as a joint project of TheGreenOffice.com and Redefining Progress, an internationally recognized pioneer in the development of sustainability indicators. The self assessment tool aims to promote sustainability in the workplace by increasing awareness of the issues and providing easy, cost effective resources for improvement.

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What is a footprint?

Your footprint represents the net impact of all the things bought, sold, and left behind in the course of daily work. Whether you are a consultant working from home, a small non-profit laboring for the greater good, or a large corporation with facilities worldwide, the unfortunate fact is that virtually all of our work activities contribute in some way to ecological deterioration and climate change. Resources are consumed faster then they regenerate; ecosystems are being polluted by toxic runoff; and the burning of fossil fuels is flooding our atmosphere with CO2. The good news is that there are a growing number of practical and affordable solutions readily available for those looking to take responsibility for diminishing their impact.

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How is my Footprint Measured?

Your Footprint is measured in a unit called a "global acre," which is an acre of land with average global biological productivity. Expressing the footprint in global acres allows comparison across different regions with varying land uses. Additionally, the use of global acres allows us to determine if you are operating at, above, or below the average capacity of Earth to renew resources and absorb waste. Based on your answers, we also determine the annual carbon dioxide emissions associated with your workplace. Carbon emissions are expressed in metric tons per year. The best way to diminish your Footprint is through resource conservation, green purchasing, and carbon offsetting. On the results page of the calculator you will find easy and cost-effective resources for implementing each of these critical strategies.

History of Our Calculator

The history of our Office Footprint Calculator™ began in 1996 when Dr. Willam Reese and Dr. Mathis Wackernagel, based at the University of British Columbia in Vancouver, Canada, developed the first footprint assessment and published the results in the book Our Ecological Footprint: Reducing Human Impact on the Earth. In 2000, Dr. Wackernagel assembled a team at Redefining Progress to further refine the footprint methodology. After these improvements, the team began widely disseminating their findings through both Refining Progress and the World Wildlife Federation. Beginning in 2004, Redefining Progress made a second round of refinements under the direction of Dr. Jason Venetoulis and Dr. John Talberth. Two years later a Footprint 2.0 was completed. At the end of 2005, a team from TheGreenOffice.com began working with Redefining Progress to develop a calculator tailored to capture and analyze the resource consumption of offices.

Assumptions & Methodology

Footprint calculations are based on five assumptions:

  1. It is possible to keep track of most of the resources people consume and many of the wastes offices generate.
  2. Most of these resource and waste flows can be converted into the biologically productive area that is required to maintain these flows.
  3. These different areas can be expressed in the same unit (global acres) once they are scaled proportionally to their biomass productivity. In other words, each particular acre can be translated to an equivalent area of world-average land productivity.
  4. Since these areas stand for mutually exclusive uses, and each standardized acre represents the same amount of biomass productivity, they can be added up to a total.
  5. This area for demand can be compared with nature's supply of ecological services (including carbon absorption), since it is also possible to assess the area on the planet that is biologically productive.

Building from these assumptions, the sequential procedures used to estimate Footprints are:

  1. Identify the world’s biocapacity, i.e. how many hectares (or acres) of crop land are dedicated to bean production. This also includes pasture land, forests, fishing area, carbon sequestration area, and built space.
  2. Normalize all biocapacity categories using the equivalence factors into global acres, i.e. making crop land, grasslands, and forest comparable using a common denominator such as net primary productivity or agricultural potential.
  3. Subtract biocapacity for the needs of non-human life.
  4. Determine the average yield factors for a hectare of biocapacity, i.e. how many tons of beans per hectare of crop land are produced.
  5. Use the biocapacity and yield factors to measure the area of biocapacity an office’s consumption and waste output requires over the course of a year, i.e. one ton of beans might require ½ hectare to grow in a particular country, and thus the footprint of two tons of bean consumption is one global hectare.

Once the footprint has been calculated in terms of global acres, the associated carbon liability for that footprint is determined using a carbon dioxide absorption factor.

Data Sources

The Office Footprint Calculator™ is primarily based on data published by United Nations agencies and the Intergovernmental Panel on Climate Change. Averages for US office resource consumption are derived using datasets provided by the US Department of Transportation, US Department of Energy, Lawrence Berkeley Laboratory, Oak Ridge National Laboratory, and other industry groups such as Special Coffee Association of America.

Use of the Calculator

Footprint and carbon liability assessments are only as good as the data used to calculate them. For this reason, it is imperative that users gather information in an accurate and precise manner.

Use of Averages

For each field within the Office Footprint Calculator™ we provide U.S. national averages to aid users looking to do a quick baseline assessment. For users looking to offset carbon emissions or make footprint data public we highly recommend the use of exact figues as inputs vary widely across industries.

Onsite Data Collection

For larger organizations, managing and coordinating data collection with employees and building managers can be a fairly involved task. TheGreenOffice.com has tools available to help organizations conduct their internal surveys. For assistance with data collection, whether you are a large or small organization, please do not hesitate to email or call at 800.909.9750 .


While the Office Footprint Calculator™ provides clear, intuitive measures of two important indicators of sustainability, it does not capture every environmental strain that also systematically undermines sustainability and carrying capacity.

Consider the following example. Footprinting ignores the effects of toxic pollution on organisms and processes that sustain Earth's life support systems. For example pollinator populations like bats and bees are disproportionately impaired by toxic pollution from pesticide applications, undermining biological productivity. The inability to capture problems of cumulative environmental contamination is particularly problematic from an energy perspective.

As explained by Venetoulis and Talberth, "while such declines may be reflected in lost biocapacity in the future, they are not reflected in negative ecological balances in the present." Thus, ironically, while ecological footprints are used as indicators of sustainability, they fail to capture the systematic erosion of earth's carrying capacity that is the basis of sustainability.

Finally, experience has demonstrated that we cannot predict all important sustainability impacts of human resource use. Examples include the unanticipated destruction of Earth's protective ozone layer by chlorofluorocarbons and other chemicals. Ozone loss was well on its way to undermining life on Earth before the problem was discovered and addressed. Another example is the unanticipated endocrine disrupting effects of many chemicals now in widespread commercial use that are impairing reproduction of wildlife populations. Emerging new technologies whose sustainability implications are largely unknown but potentially serious include widespread use of genetically engineered crops, new introductions of genetically engineered livestock and other organisms, and just emerging products of nanotechnology.

Therefore the current Office Footprint Calculator™ represents our current best understanding of the intricate balance and interactions of the Earth’s various geological and ecological systems. As technologies improve with regards to their environmental impact, so too will our tools for more accurately assessing those impacts. The current degree of accuracy of our calculations is the best in the industry and will only get better. We invite you to learn how you impact the world as we understand it today.

About Redefining Progress

Redefining Progress (RP) works with a broad array of partners to shift the economy and public policy towards sustainability. RP does this in three ways:

  1. RP measures the real state of our economy, our environment, and social justice with tools like the Genuine Progress Indicator and the Ecological Footprint.
  2. RP designs policies - like environmental tax reform - to shift behavior in these three domains (economy, environment, and equity) towards sustainability.
  3. RP promotes and creates new frameworks - like common assets - to replace the ones that are taking us away from long-term social, economic, and environmental health.

RP’s tools include rigorous indices of sustainability, groundbreaking economic policies, and solid new frameworks for re-shaping our world. RP’s partners include grassroots communities, labor unions, policymakers, academics, and businesses. RP’s efforts are largely focused on the United States because redefining progress here will have enormous global reverberations.

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