IGUANA: Much Ado About Carbon

Across Europe, this past summer brought repeated heatwaves, worsening droughts and widespread wildfires. Climate change is not something distant or abstract and the choices we make, including how we travel, are key. 

Aviation is a significant source of emissions in both the UK and the university sector. It accounts for around 10% of UK CO₂ emissions, with about 95% of UK aviation emissions arising from international flights. UK universities collectively generate roughly 340,000 tonnes of CO₂ annually from business travel, and at some research-intensive institutions, flying represents around 10–22% of the total institutional carbon footprint. These emissions are also highly concentrated, approximately 15–20% of university staff may account for 50–80% of flight-related emissions. At King’s College London specifically, business travel generated 14,834 tonnes CO₂e, highlighting travel - and particularly aviation - as an important area for institutional carbon reduction.

A 2023 study of flight reduction across academic institutions reported that business-related air travel accounted for between 11% and almost half of total institutional emissions at the institutions studied; across the wider literature, the contribution has been reported to reach around 60% in some research organisations. A second study estimated that, before the pandemic, professors and group leaders took an average of 5.8 academic plane trips a year, almost four times the 1.5 trips taken by researchers without professorial or group-leader roles.

Academic travel is therefore not a fringe problem. Universities help create the norms, expectations, funding structures and working practices that make frequent flying part of academic life. They also have a responsibility to clean up these systems rather than placing the burden entirely on individual researchers.

From skepticism to investment

When I first proposed King’s College London’s Decarbonising European Conference Travel Initiative (IGUANA), there was scepticism about whether it could work. Could we really provide researchers with a small amount of additional financial support to make travelling to European conferences by train, ferry and other lower-carbon routes a genuinely viable alternative to flying?

The challenge was that sustainable travel was often perceived as too expensive, too complicated and too time-consuming to support at scale. One of the concerns raised when I was trying to get IGUANA off the ground was that £5,000 simply wouldn't go very far and could be spent within a week or two.

But we were able to make the funding stretch, supporting 24 researchers to travel more sustainably for academic work across Europe. When the original funding period ended, I didn't want IGUANA to disappear just as we were beginning to understand what could be achieved. For the second financial year, I was able to keep the initiative running using research bench fees. It wasn't a permanent solution, but it allowed me to continue supporting journeys (another 10 ) and demonstrating that there was an appetite for a different approach to European academic travel.

Perhaps the most exciting development has come this year. IGUANA has now received financial support from the Heads of all three Schools within the Institute of Psychiatry, Psychology & Neuroscience: Professors Cathryn Lewis, Edward Bullmore and Mark Richardson. IGUANA started with a question about whether £5,000 could make any meaningful difference. We are now at a point where the IoPPN leadership has chosen to invest in helping researchers make lower-carbon travel choices.

Lessons Learnt

One of the biggest lessons from IGUANA has been that we shouldn't assume sustainable choices are impractical before giving people the opportunity to make them. There are real barriers to lower-carbon academic travel. International rail can be difficult to navigate. Tickets can be more expensive. Journeys take longer. Researchers have caring responsibilities and other commitments that mean flying will sometimes be the only practical option. IGUANA isn't about pretending those barriers don't exist, and it isn't about telling researchers they shouldn't fly. Instead, it asks what we can change when a lower-carbon journey is possible.

Sometimes the difference between flying and taking the train isn't a huge financial intervention. It might be a modest contribution towards the additional fare, an overnight stay that makes an overland journey possible, or having someone help work out a viable route.

And there have been unexpected benefits too. Researchers have described using train journeys to work, read and prepare for their conferences. There is a saying, it is not about the destination, but about the journey. 

Ultimately, I would like IGUANA to help change the question we ask when arranging European academic travel. Instead of automatically asking "Which flight should I book?", perhaps the first question can become: "Could I get there another way?"

What can you do?

Funders are increasingly asking applicants to demonstrate the sustainability measures they are putting in place, and thinking differently about conference travel is one practical and achievable way of doing that. If you are writing a fellowship or grant application and costing conference attendance, build lower-carbon travel into the budget from the beginning. Cost the train rather than automatically costing a flight, and where the journey requires it, cost an overnight stay too.

If you are a PI, lab head or research leader, encourage your team to travel by train where it is feasible. For many European destinations, it is entirely possible. But encouragement alone is not enough. Sustainable travel may require an additional travel day or an overnight stay. These realities need to be built into how we plan and support academic travel, rather than expecting researchers to absorb the additional time themselves or use their annual leave because they have chosen the lower-carbon option.

The same challenge applies at an institutional level. King’s already promotes a 5-Hour Train Rule, strongly encouraging staff and students to travel by train rather than fly when a European destination can be reached from London by rail within five hours, including destinations such as Paris, Brussels, Amsterdam and Lille.

But having a sustainable travel policy is only the first step. We also need to ask how it is being implemented: are people being actively encouraged to follow it? Do our booking and funding systems make the lower-carbon choice easy? Are we recording how people travel and whether practice is changing? And are we reviewing that information over time? A policy can set an expectation, but if we do not monitor what happens afterwards, we cannot know whether it is actually changing behaviour.

If this is something you want to talk about further, please get in touch with me, and you can read the blogs from people who have received IGUANA funding and hear about their experiences of travelling sustainably across Europe on the IGUANA blog pages.