Results
Bus vs Train CO₂ — Per-Passenger Comparison (Coach vs Regional Rail)
Enter From / To (or a manual distance), set occupancy, rail type & grid mix, and see which mode wins on CO₂e. Auto-calculates and keeps a shareable URL.
Inputs
If From/To are set, distance is auto-calculated.
🚌 Bus
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🚆 Train
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Enter a route or distance to compare.
Passengers: 1 — totals are per-person. Group total appears here.
🧭 Overview
The Bus vs Train CO₂ Calculator estimates the per-person carbon emissions for your trip based on distance, load factor, vehicle type, and—if the train uses electricity—the regional grid’s carbon intensity in gCO₂/kWh.
By combining verified emission factors and real-world occupancy data, this tool helps you make environmentally smarter travel choices and understand how factors like seat utilization and national power mix affect overall climate impact.
⚙️ Methodology & Assumptions
- Emission model: Per-person emissions = distance × emission factor ÷ load factor, with optional “upstream” (well-to-tank) uplift for energy supply chains.
- Bus modes:
- Coach (intercity) – efficient diesel power, ~25–35 gCO₂/p-km at 70–80% occupancy.
- City bus – lower efficiency and load factor, typically 90–120 gCO₂/p-km (default baseline ≈104 g/p-km @ 60% LF before upstream).
- Train modes:
- Electric regional – 0.05–0.15 kWh/p-km depending on network.
- High-speed rail (HSR) – 0.12–0.25 kWh/p-km derived from a 0.060 kWh/seat-km baseline (scaled by occupancy; ≈0.10 kWh/p-km at 60% LF) with higher average occupancy (~70%).
- Diesel rail – ~70–110 gCO₂/p-km, similar to a full coach bus.
- Grid intensity: Electric rail results depend on your region’s grid carbon factor (e.g., France ≈ 45 g/kWh, United Kingdom ≈ 220 g/kWh, Germany ≈ 380 g/kWh, USA ≈ 370 g/kWh).
- Linear distance: The map uses great-circle (as-the-crow-flies) distance between cities for a simplified comparison; actual rail routes may be 10–25% longer.
- Units: Calculations adapt automatically between km and miles, and you can switch between one-way and round-trip modes.
📊 Formula
Per-person CO₂ (g) = Distance × (EF_mode / LoadFactor) × (1 + UpstreamShare)
Where:
• EF_mode = base emission factor of the vehicle (gCO₂/km or gCO₂/kWh × energy use)
• LoadFactor = occupancy (0–1)
• UpstreamShare = optional energy supply chain uplift (e.g., +10%)
For electric trains:
EF_mode = EnergyUse (kWh/km) × GridIntensity (gCO₂/kWh)
💡 Example Calculation
Compare a 250 km one-way trip with defaults (passengers: 1, occupancy 60%, upstream +10%).
- 🚌 Coach bus (baseline 27.7 g/p-km at 60% LF):
Per-pax intensity with upstream =27.7 × 1.10 = 30.47 g/p-km
Total per person =250 × 30.47 = 7,618 g ≈ 7.62 kg CO₂e. - 🚆 Intercity electric train (0.045 kWh/seat-km at 60% LF ⇒ 0.075 kWh/p-km):
- EU avg grid 350 g/kWh:
0.075 × 350 = 26.25 g/p-km→ with upstream×1.10 = 28.9 g/p-km→250 × 28.9 = 7,225 g ≈ 7.23 kg(train lower). - Germany 380 g/kWh:
0.075 × 380 = 28.5 g/p-km→ with upstream31.35 g/p-km→250 × 31.35 = 7,838 g ≈ 7.84 kg(bus slightly lower). - France 60 g/kWh:
0.075 × 60 = 4.5 g/p-km→ with upstream4.95 g/p-km→250 × 4.95 = 1,237 g ≈ 1.24 kg(train much lower).
- EU avg grid 350 g/kWh:
Takeaway: Results flip with the grid mix—on clean grids the train wins decisively; on fossil-heavy grids the bus can be similar or lower.
🌍 Regional Grid Intensity & Emission Factors
The calculator’s default grid factors are derived from the UK Department for Energy Security & Net Zero (2025 GHG Conversion Factors) and the IEA 2024 global electricity intensity dataset.
| Region | Electric Grid (gCO₂/kWh) | Typical Rail Intensity (g/p-km) |
|---|---|---|
| EU average | 350 | ~26–30 |
| Germany | 380 | ~28–32 |
| France | 60 | ~4–6 |
| Poland | 720 | ~54–60 |
| United Kingdom | 220 | ~17–22 |
| USA (average) | 370 | ~27–31 |
Grid intensity varies daily with renewable generation. For precise results, enter your own custom gCO₂/kWh value from your country’s power operator or Ember Global Electricity Data.
🚆 Train vs 🚌 Bus — Comparative Insights
- Trains powered by renewable electricity can approach near-zero CO₂ per km.
- Diesel trains or poorly loaded buses both exceed 80–120 g/p-km; occupancy is often the dominant factor.
- On short routes (< 50 km), buses may outperform trains due to lower overhead energy for acceleration.
- Over medium–long routes (100–800 km), electrified rail generally wins by 60–95%.
📈 Typical Use Cases
- Eco-travelers comparing intercity bus vs rail journeys in Europe or North America.
- Corporate sustainability teams estimating employee travel emissions for ESG reporting.
- Universities or students quantifying carbon savings from rail-first policies.
- Planners benchmarking grid decarbonization impacts on transport CO₂ over time.
🖼️ Infographic & Visual Guide
Bars scale to the larger of the two totals. Units follow your selection (kg or lb). Round-trip & passenger count update live.
| Region | Typical gCO₂/kWh | Rail effect |
|---|---|---|
| France | ~45 | Very low rail CO₂ |
| UK | ~220 | Low–moderate |
| Germany | ~380 | Moderate |
| USA (avg) | ~370 | Moderate |
| Australia | ~520 | Higher |
| India | ~650 | Higher |
Tip: choose Custom grid in the form to match your operator’s latest figure.
- Bar lengths reflect your current inputs (distance, load factor, grid).
- Occupancy shifts results a lot: lower load = higher g/p-km.
- Grid intensity linearly scales electric rail results.
❓ Frequently Asked Questions
Is train always greener than bus?
Not necessarily. Short trips, low train occupancy, or fossil-heavy electricity can make buses competitive. On cleaner grids, trains win decisively for longer distances.
Where do the CO₂ factors come from?
They’re based on verified datasets such as the UK 2025 GHG Conversion Factors and IEA 2024 energy intensity reports, adjusted for occupancy and distance.
How accurate is the distance shown?
The map uses a great-circle distance (straight-line) between coordinates. Actual rail paths are usually 10–25 % longer; that’s why the result is labeled an estimate.
What is grid carbon intensity?
It’s the average grams of CO₂ emitted per kWh of electricity generated. Cleaner grids (more renewables/nuclear) reduce electric train emissions proportionally.
Can I compare multiple regions?
Yes. Adjust the “Grid gCO₂/kWh” field to simulate travel in different countries or import your own values.
Does this include station energy, manufacturing, or maintenance?
This simplified tool focuses on operational emissions. Lifecycle analyses (LCA) add 10–20 % for infrastructure and vehicle production.
Why do occupancy rates matter so much?
CO₂ per passenger km divides total emissions by number of riders. A bus at 25 % full emits four times more per person than one at 100 %.
Are electric buses included?
Currently no, but you can simulate one by entering a custom factor similar to an electric train with its energy consumption per km.
What if my trip has multiple legs (e.g., city bus + train)?
The full version of the Travel CO₂ Calculator lets you chain multiple modes and see total emissions.
Can I export or share results?
Yes — use the built-in Copy / Print / Export buttons to generate a sharable summary for reports or posts.
What is the average carbon dioxide emissions factor in Germany?
Germany has the sixth most carbon-intensive electricity in Europe at 381 gCO₂/kWh compared to just 56 gCO₂/kWh in France in 2023.
Official Website of the International Trade Administration
Why Electric Grid (gCO₂/kWh) for Germany is so high?
Germany's electricity grid has a relatively high CO2 intensity (\(gCO_{2}/kWh\)) compared to many other European countries due to its reliance on fossil fuels like coal and gas for backup power, despite its investments in renewables. The country's coal phase-out plan is still in progress, and the intermittent nature of solar and wind power requires significant backup capacity, often supplied by fossil-fuel power plants, which raises the overall \(CO_{2}\) emissions per kilowatt-hour.
Disclaimer:
The Bus vs Train CO₂ Calculator provides indicative results based on public emission factors and average load assumptions. Actual performance varies by operator, vehicle age, route length, and energy mix. Values are for educational and informational purposes only and not for regulatory reporting. Always consult official transport or sustainability data for verified figures.