Equivalent Carbon Dioxide: Your SME Reporting Guide

published on 13 December 2023

Reporting equivalent carbon dioxide (CO2e) emissions can seem daunting for sustainability officers at small and medium-sized enterprises (SMEs).

Yet having a solid understanding of CO2e enables creating robust emissions reduction strategies, ensuring compliance, and communicating your sustainability efforts effectively.

This guide covers everything to competently measure, report, and strategise around your organisation's CO2e footprint - empowering your sustainability efforts.**

Introduction to CO2e for SME Sustainability

Equivalent carbon dioxide (CO2e) is a standard unit for measuring carbon footprints. It expresses the impact of each different greenhouse gas in terms of the amount of CO2 that would create the same amount of warming. Understanding and using CO2e correctly allows small and medium-sized enterprises (SMEs) to accurately account for and report their overall climate impact.

For SMEs just starting their net zero journey, wrapping your head around concepts like CO2e can feel daunting. But grasped correctly, CO2e and carbon accounting will become your sustainability team’s trusty sidekicks. Let’s break down the basics:

Why CO2e Matters

  • Allows you to account for all greenhouse gas emissions, not just CO2.
  • Enables accurate carbon footprint calculations and goal setting.
  • Essential for regulatory and voluntary emissions reporting.
  • Helps track performance over time.

Getting intimate with CO2e now will pay dividends as you build out your sustainability strategy. With the fundamentals taken care of, you’ll be able to have more meaningful conversations with stakeholders about your emissions profile and reduction plans.

What is the equivalent CO2 measurement?

Equivalent carbon dioxide (CO2e) is a metric used to compare the emissions from various greenhouse gases on the basis of their global warming potential (GWP). It expresses the amount of a greenhouse gas in terms of the amount of carbon dioxide that would create the same amount of warming.

For example, methane has a much higher global warming potential than carbon dioxide. Over a 100-year period, one tonne of methane has the same global warming impact as 28-36 tonnes of carbon dioxide. Therefore, if a factory emits one tonne of methane over a year, this would be equivalent to emitting 30 tonnes of CO2e.

The CO2e metric allows policymakers, businesses and other institutions to make an apples-to-apples comparison of emissions, and develop reduction strategies accordingly. Without using CO2 equivalents, the differing warming impacts of greenhouse gases would make tracking and benchmarking emissions very challenging.

What is the difference between CO2 and CO2e?

CO2 stands for carbon dioxide, which is the most common greenhouse gas emitted in human activities. CO2e, or carbon dioxide equivalent, refers to the amount of CO2 that would create the same amount of warming impact as the total greenhouse gases actually emitted.

So while CO2 measures only carbon dioxide emissions, CO2e accounts for all greenhouse gases and expresses their warming impact in terms of the equivalent carbon dioxide amount. This allows comparisons of impacts across different greenhouse gases like methane and nitrous oxide using a standard CO2e unit.

To calculate CO2e, the amount of each gas is multiplied by its global warming potential (GWP). For example, methane has a GWP of 28-36 over 100 years - meaning its warming effect is 28-36 times greater than CO2 per unit. So 1 tonne of methane emitted would equal 28-36 tonnes of CO2e.

Using CO2e gives a more comprehensive assessment of total greenhouse gas emissions and their warming impact. This helps organisations more accurately track progress towards climate goals for carbon neutrality or net zero emissions that account for all warming gases. Reporting CO2e also meets sustainability standards like the GHG Protocol Corporate Standard.

So in summary:

  • CO2 = carbon dioxide emissions only
  • CO2e = total greenhouse gas emissions expressed as equivalent carbon dioxide warming impact

Switching from CO2 to CO2e reporting increases transparency and often reveals greater overall emissions. But it also demonstrates an organisation's commitment to more meaningful climate action.

What is an example of a CO2 emissions equivalent?

When measuring carbon emissions, it can be useful to translate the abstract concept of a "tonne of CO2" into relatable real-world equivalents that your audience can easily visualise.

For example, one metric tonne of CO2 emitted is roughly equivalent to:

  • Driving an average passenger vehicle powered by gasoline for 2,500 miles
  • Charging 120,000 smartphones
  • Burning 500 litres of diesel fuel

Putting carbon emissions into these types of equivalent terms can give your stakeholders a tangible understanding of your company's environmental impact. It also emphasizes why curbing emissions matters - those seemingly small CO2 numbers can represent very significant actual activities.

As you analyse your organisation's carbon footprint and set emissions reductions targets, considering equivalent CO2 translations is an impactful way to contextualise the data for internal teams and external audiences. The EcoHedge platform can automatically generate these types of emissions equivalents to simplify your sustainability reporting.

What is the CO2 equivalent footprint?

The CO2 equivalent footprint refers to the total climate impact of all greenhouse gases emitted, expressed in terms of the equivalent amount of carbon dioxide (CO2). This allows for a common comparison across different greenhouse gases based on their global warming potential.

The most common greenhouse gases that contribute to the CO2 equivalent footprint are:

  • Carbon dioxide (CO2)
  • Methane (CH4)
  • Nitrous oxide (N2O)
  • Fluorinated gases (hydrofluorocarbons, perfluorocarbons, sulfur hexafluoride and nitrogen trifluoride)

Each gas has a different capacity to trap heat in the atmosphere over a 100-year timeframe, known as its global warming potential (GWP). For example, methane has a GWP of 28-36 over 100 years, meaning its climate impact is 28-36 times greater than CO2 over a century.

To calculate the CO2 equivalent footprint, the amount of each gas emitted is multiplied by its 100-year GWP and then summed. This gives the total impact of all emissions in terms of the equivalent amount of CO2 needed to produce the same warming effect.

Reporting CO2 equivalent footprints allows comparisons of total climate impact across different greenhouse gases and sources. It is a standard metric used in carbon accounting and sustainability reporting by businesses, organisations and governments. Understanding your CO2 equivalent footprint is key for tracking progress and identifying priorities to reduce emissions.

The Fundamentals of CO2 Equivalent Measurement

Equivalent carbon dioxide (CO2e) is a metric that encompasses all major greenhouse gases, enabling apples-to-apples comparisons of emissions and simplifying carbon reporting. This section will clarify exactly what CO2e is and why it matters.

CO2e and Global Warming Potential Explained

CO2 equivalent (CO2e) allows different greenhouse gases to be compared on a common basis and is used to evaluate their contributions to global warming. It expresses the amount of CO2 that would create the same amount of warming as the emissions of another greenhouse gas over a specific timescale, usually 100 years.

The global warming potential (GWP) measures how much heat a greenhouse gas traps in the atmosphere relative to carbon dioxide over a period of time. It is based on the gas's atmospheric lifetime and heat-absorbing ability. For example, methane has a 100-year GWP of 28-36, meaning its global warming effect is 28–36 times greater than carbon dioxide on a per mass basis.

By converting all greenhouse gases into carbon dioxide equivalent using their GWPs, we can easily understand, track and report total emissions. This standardisation is essential for carbon accounting and setting science-based emissions reduction targets aligned with the Paris Agreement's goal of limiting global warming to 1.5°C. Tracking CO2e highlights the most impactful areas to reduce emissions across an organisation's operations and value chain. It also ensures historical emissions can be accurately compared year-over-year to demonstrate progress.

Understanding the CO2 Equivalent Unit

The universal unit for reporting CO2e is tons of CO2 equivalent (tCO2e). This represents the mass of CO2 emissions that would create the same warming impact as the actual mass of another greenhouse gas emitted.

For example, releasing 1 ton of methane gas equals 25-34 tCO2e, while 1 ton of nitrous oxide equals approximately 298 tCO2e. By converting all emissions into tCO2e using the appropriate GWPs, an organisation's total greenhouse gas footprint can be consistently tracked, evaluated and benchmarked over time.

Reporting in tCO2e enables apples-to-apples comparisons across business units, industry peers, and geographic regions when assessing climate impact. It is the standardised methodology endorsed by major environmental reporting frameworks like the Greenhouse Gas Protocol Corporate Standard. For SMEs targeting net-zero, understanding tCO2e is essential for accurately measuring, disclosing and reducing emissions.

Calculating Your Carbon Footprint with CO2e

Understanding your company's carbon footprint is an essential first step towards setting emissions reduction targets and monitoring progress. However, with multiple greenhouse gases to account for across scopes 1, 2, and 3, this can quickly become complex. Expressing your emissions in terms of carbon dioxide equivalent (CO2e) provides a standardised approach to quantify and compare impacts across gases and categories.

Using a CO2 Equivalent Calculator

Specialised CO2 equivalent calculators make converting raw emissions data into CO2e metrics straightforward. After entering figures on fuel, electricity, waste, etc., the calculator automatically applies gas-specific CO2 equivalent formulas and CO2 equivalent tables listing the latest global warming potential (GWP) values. This transforms all emissions into tonnes of CO2 equivalent (tCO2e) - a universally recognised unit for carbon footprinting and sustainability reporting.

Online CO2e calculators simplify data input with customisable templates for capturing all material emission sources. Built-in reporting dashboards then allow slicing and dicing footprints by scope, activity, or facility. For SMEs new to sustainability accounting, choosing a calculator with exportable reports, infographics, and stakeholder engagement tools is recommended. This enables easy communication of environmental impacts to customers or leadership teams.

Leading CO2e calculators also facilitate forecasting by letting users model different operational scenarios and set science-based targets. This assists companies in charting pathways towards net zero by quantifying projected savings from emissions reduction activities.

The CO2 Equivalent Formula in Action

The CO2e concept itself is derived from the global warming potential values assigned to different greenhouse gases based on their heat-trapping efficiency over 100 years. Specifically:

CO2 Equivalent Formula:

tCO2e = (Mass of gas * GWP) / 1,000


  • tCO2e = Equivalent carbon dioxide emissions in metric tonnes
  • Mass = Amount of gas released measured in kg or metric tonnes
  • GWP = Global warming potential value

For example, methane has a GWP of 28. This means 1 tonne of methane has the same global warming impact as 28 tonnes of carbon dioxide.

Let's apply this to a sample SME with the following annual emissions:

  • 60 tonnes CO2 from heating systems
  • 10 tonnes methane from agriculture practices
  • 15 tonnes nitrous oxide from industrial activities

Using IPCC GWP values:

  • Methane GWP = 28
  • Nitrous oxide GWP = 265


CO2 emissions = 60 tCO2
Methane emissions = (10 t * 28) / 1,000 = 0.28 tCO2e Nitrous oxide emissions = (15 t * 265) / 1,000 = 3.975 tCO2e

Total tCO2e = 60 + 0.28 + 3.975 = 64.255 tCO2e

Understanding how to convert all greenhouse gas data into comparable CO2 equivalent figures is key for credible carbon reporting across the value chain.


Understanding greenhouse gas emissions can be complex for small and medium enterprises new to sustainability reporting. A key concept is equivalent carbon dioxide (CO2e), which allows businesses to compare emissions across different greenhouse gases using a common unit of measure. This simplifies reporting and aids in identifying reduction opportunities.

A CO2 equivalent table contains key data to convert gas quantities into CO2e. Let's see how it works.

What is a CO2 Equivalent Table?

A CO2e table provides emissions factors, known as global warming potential (GWP), for major greenhouse gases like methane, nitrous oxide, and others. For example, methane has a much higher warming impact than carbon dioxide. The table allows converting gas quantities into the CO2e unit using the appropriate GWP.

Image: Sample excerpt from a CO2e conversion table showing emissions factors

The most common emissions factors used are from the IPCC over a 100-year timeframe. With the factors, 1 ton of methane equals 25 tons of CO2e. This standardised approach aids in preparing GHG inventories and carbon reports consistent with top reporting protocols.

Calculating CO2e using the Emissions Factors

The CO2e formula is simple:

CO2e = Gas Quantity x GWP

For instance, a factory emitting 2 tons of methane yearly would calculate its CO2e as:

CO2e = 2 tons CH4 x 25 = 50 tons CO2e

Without converting to CO2e using the emissions factors, the methane emissions impact would be greatly underreported. Facilities can use the coefficients to convert all site emissions into CO2e accurately.

Choosing the Right Emissions Factors

Sustainability managers should select emissions factors aligning with their inventory methodology and reporting protocol. Most SMEs reference the latest IPCC reports covering a 100-year time frame.

However, some reports may utilise 20, 50 or 500-year GWP values instead to assess near-term and longer-term climate impacts. Know your reporting requirements before building your CO2e inventory.

Streamline Conversion with Emissions Tracking Software

While a CO2e table aids manual conversion, emissions tracking software can automatically handle these calculations. Solutions like EcoHedge Lifecycle integrate a centralised database of emissions factors sourced from the IPCC and EPA.

Built-in conversion formulas seamlessly calculate CO2e across all input data. This removes manual work, minimises errors, provides auditable tracking, and ensures up-to-date factors are always applied. Consider automation to efficiently scale CO2e reporting across facilities and gases.

Accurately assessing total greenhouse gas impact is vital for sustainability planning. A CO2 equivalent table and emissions tracking software are invaluable tools to standardise gas quantities into comparable CO2e units. Consistent application of emissions factors is key to transparent carbon accounting.

The Role of Methane in CO2 Equivalent Reporting

As an SME seeking to measure and report your carbon footprint, it's essential to understand the concept of CO2 equivalent emissions, especially when accounting for potent greenhouse gases like methane. Though CO2 receives the most attention, methane has a global warming potential (GWP) 28-36 times greater than CO2 over a 100-year period. This means methane contributes significantly more to climate change per unit than CO2.

When aggregated together based on their relative GWP, greenhouse gas emissions can be expressed in terms of CO2 equivalent (CO2e). This allows for an apples-to-apples comparison of impacts across different gases. Simply put, 1 ton of methane emitted has the same effect on global warming over 100 years as 28-36 tons of CO2.

To calculate your company's total CO2e footprint, you'll need to multiply your methane emissions from sources like equipment leaks, livestock, and waste by its assigned GWP value - whether using an internal calculator or the EcoHedge software. Proper accounting here is crucial for an accurate carbon inventory.

Though methane management may seem complex for SMEs initially, simple measures like repairing equipment leaks and diverting organic waste from landfills can significantly reduce your CO2e footprint at little cost. As stakeholders demand more climate transparency through initiatives like CDP disclosure, having robust CO2e figures will prove vital.

By properly factoring in potent GHGs like methane into your net emissions using CO2e as a standard measure, your SME can make more informed decisions on reduction strategies. This allows focusing efforts on methane sources with an outsized warming impact relative to costs. With methane's short atmospheric life of 10-12 years unlike CO2, cuts also quickly benefit our climate.

Mandatory CO2e Reporting and Compliance

As sustainability reporting regulations gain momentum globally, small and medium enterprises (SMEs) must prepare to measure, disclose and reduce their carbon emissions. Understanding equivalent carbon dioxide (CO2e) reporting concepts is key to compliance. This guide will help SMEs grasp the regulatory landscape and best practices to transparently communicate their environmental impact.

Why CO2e is Vital For Compliance

Reporting CO2e or carbon dioxide equivalent allows companies to account for all greenhouse gases they emit, not just carbon dioxide. Converting emissions like methane and nitrous oxide into a standard CO2e unit enables fair comparison and action across all industries towards shared climate goals.

Many emerging regulations worldwide now mandate disclosure and reduction of CO2e emissions. For example, CSRD in Europe requires high-impact companies to report CO2e from 2024. Other major schemes include SEC rules in USA and UK's SECR policy. So learning CO2e principles is vital for SMEs to ready themselves for compliance.

Demystifying Key CO2e Terminology

Understanding commonly used terms will help sustainability teams report CO2e accurately and derive the best carbon reduction strategies:

  • Global Warming Potential (GWP) - A factor estimating how much heat a greenhouse gas traps in the atmosphere relative to CO2 over 100 years. For instance, methane's GWP is 28-36, meaning its global warming effect is 28–36 times greater than CO2 over a century.
  • tCO2e - Tonnes of carbon dioxide equivalent. The universal unit for reporting CO2e emissions. Obtained by multiplying actual emissions by the gas's GWP factor. Enables fair consolidation and comparison of impacts across gases.
  • Scope 1, 2 and 3 - Categories defined by the GHG Protocol for reporting CO2e emissions across a company's activities. Scope 1 is direct emissions, Scope 2 is indirect emissions from purchased energy, while Scope 3 includes value chain emissions.

Best Practices For Compliant CO2e Reporting

Follow these tips to ensure smooth compliance with current and emerging CO2e regulations globally:

  • Calculate your emissions accurately using verifiable data and methods aligned with GHG Protocol. Leverage automated software to remove manual errors.
  • Prioritise reporting of Scope 1 and 2 emissions initially if Scope 3 seems complex. But have a roadmap to track value chain emissions over time.
  • Offset residual emissions after reduction efforts to reach net-zero goals, using certified carbon credits.
  • Disclose CO2e annually in sustainability reports and communicate reduction plans openly with stakeholders.

With preparations focused on robust CO2e measurement, reporting and reductions, SMEs can transform risks of non-compliance into opportunities to lead in ethical, green business practices.

Best Practices for CO2e Data Management and Quality

Accurate carbon accounting starts with robust data collection and management processes. Here are some best practices to ensure high-quality CO2e data:

Use Primary Data Sources

Seek out primary emissions data from utility bills, fuel purchases, supply chain records etc. This minimises estimation uncertainties. You can still use some secondary data to fill gaps.

Perform Regular Meter Readings

Conduct frequent meter readings for electricity, fuel, waste etc., at least quarterly. This provides actual usage data minimising the need for projections. Usage patterns may shift over time so frequent readings allow prompt adjustments.

Establish Responsibilities

Clearly define roles for data collection, analysis and reporting. Appoint sustainability managers per site/department to track sources like travel, shipping etc. Central coordination and oversight will ensure standardisation.

Track All Emissions Sources

Account for all direct and indirect emissions from operations, supply chain etc. Missing sources can undermine overall reductions so strive for 100% coverage through robust tracking.

Set Internal Reporting Deadlines

Create a timeline for collating emissions data from all sources prior to external reporting. This allows time for verification, corrections and ensuring accurate CO2e figures for publication.

Perform Regular Audits

Conduct internal verification of reported emissions via energy audits, data reviews etc. Also pursue external assurance periodically. This scrutiny builds accountability and trust in published CO2e data.

Accurate carbon accounting relies on systematic data collection, coordination across the organisation, and continuous auditing. Adopting these best practices paves the way for quality CO2e data and trusted sustainability reporting.

Creating Impactful CO2e Reduction Strategies

Reducing your small or medium-sized enterprise's (SME's) carbon footprint is crucial for meeting net-zero emissions goals and demonstrating climate leadership. However, with limited resources, it can be challenging to know where to start. This guide provides practical tips for developing realistic yet impactful CO2e reduction strategies tailored to your business's needs.

Set a Baseline

The first step is using your CO2 equivalent calculator to measure your current emissions across scopes 1, 2, and 3. Understanding your baseline carbon footprint allows you to pinpoint the largest sources of emissions and opportunities to reduce them. Don't forget to factor in equivalent carbon dioxide emissions from potent greenhouse gases like methane.

Conduct an Emissions Hotspot Analysis

With a baseline established, conduct an in-depth hotspot analysis to identify your company's largest emissions sources. For most SMEs, these hotspots fall into several key categories:

  • Transportation: Fleet vehicles, employee commuting, business travel
  • Facilities: Energy usage for lighting, HVAC systems, computing
  • Supply chain: Raw material extraction, manufacturing, distribution

See where your company's emissions are concentrated so you can focus reduction efforts accordingly.

Set Reduction Targets

Now it's time to set some goals! Common reduction targets include decreasing total CO2e by 25-50% over 5-10 years. When setting targets, ensure they are:

  • Realistic based on emission hotspots and reduction opportunities
  • Measurable using your carbon accounting software
  • Time-bound with set target dates

Incremental interim targets allow you to track progress year-over-year.

Develop an Emissions Reduction Plan

With your targets defined, develop a comprehensive plan of action leveraging proven strategies like:

  • Switching to renewable energy
  • Improving equipment/fleet fuel efficiency
  • Changing manufacturing processes
  • Engaging staff to develop ideas

Refer to best practices for your industry to incorporate relevant tactics. Update stakeholders as you execute initiatives from this plan over time.

By following this structured approach and accessing the right carbon accounting tools, your SME can make great strides towards hitting net-zero - all while adding value and engaging key audiences. Reach out for additional guidance tailoring an effective CO2e reduction plan for your organizational needs.

Synthesising Your CO2e Efforts into Sustainability Reporting

Sustainability reporting is becoming an integral part of doing business in today's world. As companies aim to reduce their environmental impact, tracking and reporting emissions data in a standardised way is crucial. This is where the concept of CO2 equivalent (CO2e) comes in handy.

CO2e allows you to account for different greenhouse gases using a common denominator based on their global warming potential. By converting emissions data to equivalent carbon dioxide units, you can easily compare, aggregate and report the overall climate impact of your operations.

Here's a quick guide on effectively integrating CO2e data into your sustainability reports:

Step 1: Collect Relevant Emissions Data

First, take stock of your emissions footprint across the value chain. This includes direct emissions from owned operations as well as indirect emissions from purchased goods/services, transportation, waste disposal etc. Based on your business activities, identify the applicable GHG categories and ensure consistent tracking over time.

Step 2: Convert Emissions Data to CO2e

Next, convert the emissions data of different GHGs like methane, nitrous oxide etc. into equivalent units of CO2 using standard conversion metrics. This allows aggregation of the data into a single uniform metric. For reference, common conversions are:

  • 1 ton of Methane = 25 tons of CO2e
  • 1 ton of Nitrous Oxide = 298 tons of CO2e

With CO2e figures on hand, gain perspective by analysing year-on-year emissions trends. This allows you to identify priority areas for reduction efforts aligned to science-based climate targets. Share insights across teams to drive engagement.

Step 4: Report CO2e Performance

Finally, communicate your climate performance through sustainability reports. Cover CO2e reduction achievements, ongoing initiatives, future goals etc. Reports reassure stakeholders of intent, progress and transparency. An increasing number of companies now issue dedicated climate/TCFD reports as well.

With growing pressures to demonstrate climate action, strategic CO2e measurement and reporting will prove key to staying ahead of the curve. Reach out for customised solutions that make sustainability reporting efficient yet impactful for your enterprise.

Encapsulating CO2e Insights for SMEs

Equivalent carbon dioxide (CO2e) is a crucial concept for SMEs to understand as they embark on their sustainability reporting journey. By converting all greenhouse gas emissions into their carbon dioxide equivalent values, companies can compare impacts and identify priority areas to reduce environmental footprint.

Some key takeaways on CO2e for SMEs:

  • Using CO2e enables apples-to-apples comparisons across different greenhouse gases based on their global warming potential. This allows tracking comprehensive climate impact rather than just carbon dioxide emissions.
  • Relying on universal standards like the Greenhouse Gas Protocol provides credibility and ensures consistency in sustainability disclosures across companies.
  • Online CO2e calculators and emissions factors databases make determining CO2e values for various activities and materials accessible. Automated carbon accounting software can further lift this burden off sustainability teams.
  • Reporting CO2e alongside scopes 1, 2, and 3 paints an accurate, transparent picture of a company's holistic climate footprint for both internal and external stakeholders.

With these insights, SMEs can feel empowered in making CO2e reporting a routine sustainability practice. The focus now shifts to climate action - utilising the greenhouse gas emissions data to implement targeted carbon reduction strategies that put companies firmly on the path to net-zero.

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