Carbon emissions are greenhouse gases, mainly carbon dioxide, released into the atmosphere from activities like flying, driving, and using energy.
What Are Carbon Emissions?
Carbon emissions are the greenhouse gases—primarily carbon dioxide—that are released into the air from burning fuel or using energy.
This matters because these gases trap heat in the atmosphere and drive climate change. For example, a single round-trip flight from New York to London can emit as much CO₂ per passenger as driving a typical car for months.
In business travel and expense management, carbon emissions reveal the environmental impact of trips, payments, and vendor choices. Companies track these numbers to meet sustainability goals, answer investor questions, comply with regulations, and build more responsible travel programs.
Most corporate travel programs focus on trip-level emissions from:
Air travel
Rail travel
Car travel (rental, taxi, and ride-hail)
Hotel stays
Understanding Carbon Emissions in Detail
Key Components of Carbon Emissions
When companies discuss carbon emissions from business travel, they typically refer to:
Direct fuel use
- Jet fuel burned on flights
- Gasoline or diesel used in rental cars or company vehicles
Indirect energy use
- Electricity consumed by hotels, offices, and rail systems
- Power behind digital tools, data centers, and payment systems
Lifecycle impacts
- Production and maintenance of planes, trains, and cars
- Construction and operation of hotels and airports
Modern platforms like Navan Travel and Navan Expense help estimate and surface these emissions automatically at booking and in reporting.
Carbon emissions tracking has evolved from a nice to have to a must-have:
Before 2010: Emissions reporting was rare and basic. A few companies bought carbon offsets, often manually.
2010–2018: As ESG (environmental, social, and governance) reporting grew, travel management companies started offering high-level carbon reports.
2019–2022: Regulatory and investor pressure increased. Tools began showing emissions per trip and per traveler, not just annual totals.
Today: Leading platforms like Navan build emissions data directly into search, booking, policy, and analytics.
Types of Carbon Emissions (Scopes 1, 2, and 3)
Most companies follow the Greenhouse Gas Protocol (GHG Protocol). Business travel emissions are typically classified under Scope 3, Category 6 (Business Travel) and sometimes Category 7 (Employee Commuting).
Scope
Explanation
1
Direct emissions from company-owned vehicles and fuel
2
Indirect emissions from purchased electricity, heating, and cooling
3
All other indirect emissions, including most business travel
Why Carbon Emissions Matter
Companies that understand and manage carbon emissions from travel typically achieve better compliance, lower costs, and stronger ESG performance.
Here is why:
Regulatory and Stakeholder Pressure
Governments, investors, and customers expect clear, accurate emissions data. Poor reporting can lead to fines or lost business.
Cost and Efficiency
Trips that emit less often cost less. Shorter flights, direct routes, virtual meetings, and rail travel can reduce both CO2 and spend.
Talent and Brand Perception
Employees want to work for responsible companies. A visible, credible carbon strategy helps attract and retain talent.
Risk Management
Climate risk is business risk. High-emission travel patterns may face higher taxes, fees, or reputational damage in the future.
Key actionable benefits:
Better decision-naking: Compare CO2 per dollar or CO2 per trip to guide policies and vendor negotiations.
More targeted travel policies: Build rules that nudge travelers toward low-carbon options, such as rail for trips under four hours or direct flights only.
Stronger ESG reporting: Give finance and sustainability teams cleaner data for annual reports, audits, and investor requests.
Proof of progress: Show real, year-over-year reductions—not just promises.
How Carbon Emissions Work in Practice
1. How Emissions Are Calculated
Travel and expense platforms typically combine:
Activity Data:
Flight segments, cabin class, and distance
Hotel nights and location
Car type and distance or fuel
Rail distance and class
Emission Factors:
Standardized numbers from third-party-audited sources like DEFRA, ICAO, or other recognized bodies
Expressed as “kg CO2e per passenger-km or a similar unit
Calculation Logic:
Multiply activity by the emission factor
Adjust for cabin class, aircraft type, or occupancy when possible
Output per-trip and per-passenger emissions
Modern platforms like Navan automate this process using booking data and built-in calculation models, then surface the results in dashboards.
2. The Traditional Manual Approach
Travelers book flights and hotels through multiple channels.
Finance teams export card and expense data into spreadsheets.
Sustainability teams apply generic emission factors to rough distance estimates.
Many trips are missing or misclassified.
Reports are late, incomplete, and difficult to trust.
This approach often results in under-reporting and frustrating back-and-forth between teams.
3. The Modern Automated Approach
Booking:
A traveler searches in a tool like Navan.Emissions estimates appear next to each option (e.g., “This option emits 20% less CO2”).Policy nudges or blocks high-emission options for short-haul trips.
Travel:
The system records exact flight segments, hotel nights, and car types.No manual emissions data entry is needed from travelers.
Expense and Reconciliation:
Navan Expense or similar tools link card transactions to trips.You get one clean dataset for both cost and carbon.
Reporting and Action:
Dashboards show emissions by department, route, vendor, and traveler.You can adjust policies, for example, “Use rail instead of air under 400 km in Europe.”You set targets and track progress quarterly.
Common Challenges in Tracking Carbon Emissions and Their Solutions
Challenge 1: Incomplete or Poor-Quality Data
This occurs when trips are booked outside approved channels or when expense data is not linked to itineraries.
Solution: Centralize bookings through one platform and integrate corporate cards, your HRIS, and expense tools. Modern platforms like Navan address this by combining travel and expense in one system, giving you clean, trip-level emissions data.
Challenge 2: Confusing or Inconsistent Calculation Methods
This occurs when different teams or vendors use different emission factors or assumptions.
Solution: Choose a standard (e.g., DEFRA or ICAO) and document it. Use one system to calculate emissions for all travel and align with your sustainability team.
Challenge 3: Low Traveler Engagement
This occurs when travelers cannot see the impact of their choices or when policies feel arbitrary.
Solution: Show emissions at the time of search and booking, not just in annual reports. Nudge travelers with simple labels like “Lowest CO₂” and highlight company goals.
Challenge 4: Over-Reliance on Carbon Offsets
This occurs when companies buy offsets instead of changing travel behavior.
Solution: Prioritize reduction first, then use offsets for what you cannot yet avoid. Use data to set real reduction targets by route, department, or trip type.
Challenge 5: Difficulty Proving ROI
This occurs when sustainability and finance data live in separate systems.
Solution: Connect carbon data with spend data. Show that “switching 40% of short-haul flights to rail reduced emissions by X% and saved Y dollars,” for example.
Carbon Emissions vs. Related Concepts
You will often see carbon emissions discussed alongside carbon footprint and carbon offsetting. They are related but not the same. Here's how to differentiate between them:
Aspect
Carbon Emissions
Carbon Footprint
Carbon Offsetting
What it is
Actual greenhouse gases released
Total emissions linked to an entity or activity
Actions to compensate for emissions
Scope
A specific flow of gases (e.g., from a flight)
A broader picture over time (year, project, company)
Projects that remove or avoid CO₂ elsewhere
Use in travel
Emissions per trip, per segment, or per traveler
Annual travel footprint across the company
Optional projects like tree planting or renewable energy funding
Goal
Measure and reduce
Understand total impact
Compensate for what remains
In Short:
➡️ Carbon emissions are the building blocks.
➡️ A carbon footprint is the sum of those building blocks.
➡️ Offsets are one possible response, but only after you work to reduce emissions.
Related Terms and Concepts
Understanding carbon emissions is easier when you know these related concepts:
Carbon footprint: The total amount of greenhouse gases caused directly and indirectly by a person, company, or activity. Your business travel carbon footprint is the sum of all travel-related emissions over a period.
Carbon offset: A project or credit that is meant to “cancel out” emissions by reducing or removing CO2 elsewhere. Offsets are common in travel programs but are now expected to supplement, not replace, reduction efforts.
Sustainability policy: Guidelines that explain how your company plans to reduce its environmental impact. This policy often includes rules about when to fly, when to use rail, and when to meet virtually.
ESG reporting: Environmental, social, and governance reporting that many companies provide to investors and regulators. Travel-related carbon emissions are a key part of the “E.”
Scope 3 emissions: Indirect emissions in your value chain, including most business travel. These are usually much larger than Scope 1 and Scope 2 combined.
Travel policy: The rules for booking trips, such as allowed cabin classes, preferred suppliers, and approval flows. A modern travel policy includes emissions-related guidance and nudges.
Virtual meetings/travel substitution: Using video conferencing or collaboration tools instead of physical travel. This is a major lever for cutting travel emissions.
Emission factor: A standard number stating how much CO2 is emitted per unit of activity (e.g., per passenger-kilometer flown). It is used to calculate emissions from trip data.
FAQ
Start by centralizing your travel data. For each flight, hotel, train, and car rental, you need to collect key data like distance, cabin class, and number of nights. Then, apply recognized emission factors from sources like DEFRA or ICAO. A platform like Navan automates this process, applying these factors automatically to give you per-trip and aggregate emissions data.
Carbon emissions are the actual greenhouse gases released from a specific activity, such as a single flight. A carbon footprint is the total emissions from all activities over a period, like all of your company’s travel in a year. Emissions are the individual pieces; the footprint is the full puzzle.
You can use three main levers: avoid, shift, and improve. Avoid nonessential trips by encouraging virtual meetings. Shift travel from planes to rail or from business to economy class when it's reasonable. Improve by choosing more efficient airlines, direct routes, and greener hotels. With Navan, you can build your policy to guide these choices, educate travelers on their impact, and track the results.
They are estimates, not perfect measurements, but they are useful and directionally accurate. Accuracy depends on the quality of your data and the emission factors used. Using exact routes, cabin classes, and nights improves precision. The key is to use a consistent, transparent method so you can compare results over time and between options.
Reducing emissions means changing behaviors and choices so less CO2 is released in the first place. Buying offsets means paying for projects that claim to reduce or remove CO2 elsewhere. Regulators and investors increasingly prefer actual reductions, with offsets used only for emissions you cannot avoid.
Emissions data can influence which trips get approved, which routes and modes are preferred, and which vendors you choose. For example, your policy might require rail for trips under four hours or ban business class on routes under a certain distance. Navan can enforce these rules in the booking flow and highlight lower-emission options for travelers.
Work with your finance and sustainability teams to define the scope: which trips, employees, and vendors to include. Use a consistent methodology and a single source of truth from an integrated travel and expense platform like Navan. This allows you to export annual totals by Scope 3 category, region, and business unit, and to document your assumptions and emission factors.
They can be, especially for long stays and frequent trips. Hotel emissions come mainly from energy use for heating, cooling, and electricity. Some hotels have strong sustainability programs, while others do not. Including hotel emissions in your reporting helps you choose greener partners and encourage shorter or combined trips.