Sustainable Business Travel

  Panorama picture of Aachen Copyright: © Martin Braun  

In our Sustainability Mission Statement, the members of RWTH jointly committed themselves to consider sustainability in all spheres of action, processes, and decisions. The focus is also on business trips, especially air travel, as these are one of the largest emission factors at universities.

Within RWTH, awareness of the impact of one's own mobility behavior on the environment is to be raised. In addition to actively inviting members to reflect on their own behavior, internal projects in particular, such as the Climate Fund, should offer opportunities and motivate people to make their own mobility behavior more sustainable.


Pilot Project: Internal Climate Fund

Of course, scientific exchange and the cultivation of social relationships include personal encounters in the context of meetings, conferences and shared interaction. However, the last few years have also shown us that exchange can often also be carried out effectively in a digital context.

For this reason, and in order to jointly achieve the goal of a climate-neutral RWTH, business trips should always be questioned as to whether or not they are necessary. Particularly in the case of trips within Germany, it should be examined whether these can be carried out by rail (see text below), if these are not completely avoidable.

In addition, the project "Responsible Business Travel - Pilot Project Climate Fund" offers the opportunity to counteract the climate-damaging effect of (non-avoidable) air travel.

In order to offer this option in addition to the political framework conditions and thus to implement the wishes of many employees, an internal solution has been developed.

Fixed payments

During the trip request, the workflow (RAFAEL) contains the option to specify whether compensation for the trip is desired. The following flat rates have been defined:

Flights within Germany: 10 euros

Flights within Europe: 18.50 euros

Intercontinental flights: 68.50 euros

The fixed rates are based on average CO2 emissions for the respective distance category according to the Federal Environment Agency. The average values were offset against a CO2 price of 50 euros per metric ton. The CO2 price was determined based on research into political, economic and scientifically used and/or recommended values.


Participating on a voluntary basis in the climate fund is possible for each business trip during the trip application process. Participations per institute are recorded and settled on a quarterly basis. This amount is transferred from institute funds to the climate fund. To make clear the commitment of university leadership to this initiative, the funds generated will be co-funded by the central budget. The cascade model underlying the co-financing "Übersicht Pilotprojekt Klimafonds (de)" can be found here or in the download section below.

The climate fund budget will be used for climate-friendly measures on campus.

You will be regularly informed about the use of funds and the impact they generate on this website.

  Ulrich Rüdiger Copyright: © Martin Braun

Since the success of the project depends on the voluntary participation of the travelers, I would like to encourage you to take part in it and thereby make an active contribution to a more sustainable RWTH and to a future worth living.

Univ.-Prof. Dr. rer. nat. Dr. h. c. mult. Ulrich Rüdiger, Rector


The pilot project will be evaluated after three years and a decision made on whether it will be continued or not.

If you have any questions, comments or ideas, please contact us at any time at


FAQs on the internal climate fund pilot project

Which WBS Elements can be Used to Make Deposits to the Climate Fund?

For participation in the climate fund, central WBS elements must be added for each unit (institute/department/facility). Only WBS elements with central state funds can be used for this purpose.

The reason for this is that compensation has not yet been provided by third-party funding sources or, in exceptional cases (DFG projects), it is linked to certain conditions that do not provide support for regional projects.

Do I Have to Participate in the Climate Fund?

No, the internal climate fund is a completely voluntary project. This means that each unit can decide whether to allow the respective employees to participate. In addition, the business travelers decide for each business trip whether they want to participate by making the appropriate selection in RAFAEL.

If my Unit Participates in the Climate Fund, Does all Travel Have to be Included?

No, the voluntary nature of the program is the central aspect and it enables individuals to act as they wish. Each unit can decide for itself whether to allow full participation by business travelers or to set its own limits. For example, internal decisions can be made to participate only for national air travel. This decision must be publicized within the unit to ensure proper traveler participation.

Can I Include my air Travel from DFG Projects in the Internal Climate Fund?

Since December 2020, the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) allows compensation for business trips within DFG-funded projects. The DFG's guidelines for the use of compensation do not allow support for local projects at research institutions. As such, this cannot be connected with the internal climate fund of the RWTH as yet. Information on the procedure for compensation within DFG projects can be found on the DFG website.


Flugreisen vermeiden – Emissionen sparen

Help With Deciding Whether to Travel by Air

Business trips reflect a fundamental structural sustainability dilemma. On the one hand, the responsibility of society and thus also of the University toward the environment, and on the other hand, the need to share ideas. There is no standard answer to the question of which factor is to be valued more highly. Instead, each individual must make their own decision depending on the occasion.

To help travelers in their decision-making process, they can use this decision tree as a guide. With the help of four short questions, they can reflect on whether a business trip (by air) should be taken or whether other alternatives can be considered.

What Else Can I Do?

Campaign: #unter1000 mach ich's nicht!

Those who support this initiative

  • Avoid flights covering distances less than 1,000 kilometers
  • Use trains and buses or video and telephone conferencing as alternatives
  • Stand for mobility change
  • Identify needs for action

Offsetting Travel Emissions in DFG Projects

Since December 2020, the German Research Foundation, DFG for short, has made it possible to finance compensation payments for environmental impacts of business travel in research grants or in funded projects from the grant.

Spread the Word!

Share this website, links, ideas, and/or calls with your colleagues or even your personal contacts. Encourage them to join in to maximize your own climate impact!


Comparing Transportation – Train vs. Plane

A map with travel destinations of RWTH employees marked. Various lines show the five most frequent European destinations and the four most frequent domestic flight connections from Aachen. An image comparing transportation, an alternative text explanation is available at the bottom of the page.

The business travel data of RWTH employees from 2019 was taken as an example here. RWTH employees made a total of approximately 25,400 business trips in 2019. Approximately 6,000 (about 25 percent) of these business trips were made by air, with around 1,650 of these being domestic flights.

Different parameters can be used to illustrate the different environmental impacts of travel by air, rail, and car.

The image above shows the five most frequent European destinations and the four most frequent domestic flight connections: Paris, Geneva, Zurich, Barcelona, Vienna, as well as Hamburg, Berlin, Dresden, and Munich. The image shows the respective travel time by train or plane, including transfer to the airport or train station starting at the RWTH Main Building (Templergraben 55). The CO2 emissions of the trip are also shown.

The evaluation clearly shows that air travel produces many more CO2 emissions than the same trip by rail.

The comparison of travel duration also shows the advantages of rail travel. Comparison data often does not include the journey to the airport or time for check-in, security checks, and boarding. Airlines recommend arriving at the airport approximately two hours before departure to allow enough time for these procedures. Even if you check in yourself, you should still allow approximately one hour for security checks and boarding. These are not yet included in the evaluation so about one to two hours would always have to be added to the flight duration indicated in the image.


Alternative Text to the Image Comparing Means of Transportation

The image shows a map marking different travel destinations that RWTH employees may take, with Aachen in the center of the map. From Aachen, various lines point to the five most frequent business travel destinations in Europe and the four most frequent domestic flight connections: Paris, Geneva, Zurich, Barcelona, Vienna, as well as Hamburg, Berlin, Dresden, and Munich.

Besides the destination, the duration of the trip is displayed, as well as the CO2 emissions generated by rail or air travel to the destination.

(From Aachen)
Travel Duration by Train in Hours and Minutes CO2 Emissions
by Train
Travel Duration by Plane in Hours and Minutes CO2 Emissions
by Plane
Hamburg 5:20 1.72 kg 2:34 80.59 kg
Berlin 5:40 2.27 kg 2:49 108.93 kg
Dresden 7:22 2.25 kg 2:44 110.99 kg
Vienna 9:35 33.48 kg 3:09 172.6 kg
Munich 5:42 2.75 kg 2:44 110.58 kg
Zürich 6:41 17.6 kg 2:44 102.16 kg
Geneva 9:05 22.78 kg 4:24 126.6 kg
Barcelona 13:29 45.74 kg 5:49 258.39 kg
Paris 2:51 14.44 kg 2:49 91.48 kg