Ingmar Rentzhog wearing the “Make Science Great Again” hat while speaking on the “Decarbonising Businesses” stage at Economist Sustainability Week in London on March 3. Climate solutions require open dialogue and a science based approach to replacing fossil fuels with better alternatives. Photo: The Economist.

Last week, I shared a story about flying with my family after ten years of avoiding flights.

It was a very personal and somewhat fragile story for me to share publicly.

The discussion that followed reveals a deeper question facing the climate movement today: how do we accelerate the phase-out of fossil fuels while still allowing people the freedom to travel, connect, and explore the world?

For this trip, we chose a non-fossil alternative by purchasing Sustainable Aviation Fuel (SAF) that matched the flight’s full fossil fuel use.

On We Don’t Have Time, the discussion has been constructive, thoughtful, and respectful. Many people have also written very encouraging messages, saying they appreciate that I dare to talk openly about solutions that already exist in aviation, even if they are not yet perfect.

On social media, outside our platform, some reactions have been much harsher. There has been strong criticism, and in some cases, personal attacks directed not only at me, but also at my family. That kind of tone does not move the climate conversation forward.

At We Don’t Have Time we believe in dialogue. Solving the climate crisis will require many perspectives, honest conversations, and the ability to respectfully disagree while still working toward the same goal.

At the same time, the intensity of the reaction tells us something important. When discussions about real solutions create strong emotions, it often means we are touching on one of the defining questions of the transition.

Most people who care about the climate agree on the destination. But we do not always agree on the best path to get there.

Different people who care deeply about the climate often come to different conclusions about the best path forward.

The transition away from fossil fuels is not a simple or black-and-white question. That is exactly why open dialogue matters. So instead of talking past each other, let us ask the question openly.

What do you think is the best way forward?

1. Reduce first
We should sharply reduce consumption and mobility across society, phase out fossil fuels as fast as possible, and accept major lifestyle changes and sacrifices in the short term. Only once fossil fuels are largely eliminated should we scale technologies that allow higher levels of consumption again.

2. Technology first
We should focus primarily on scaling clean technologies as fast as possible. Innovation and markets will replace fossil fuels without requiring major limits on people’s lifestyles.

3. Both together
We should phase out fossil fuels while at the same time embracing and scaling non fossil solutions, even if they are not perfect yet. Regulation and innovation should move in parallel.

Vote and share your reasoning in the comments. We will publish the results next week.

The goal is not that everyone agrees on every step. The goal is that we move forward together toward the same destination: a prosperous and fossil free future where humanity has learned to live within the planetary boundaries. Thanks for being part of the We Don’t Have Time community.

Neste, the world’s leading producer of sustainable aviation fuel (SAF), has started producing SAF at its renewable products refinery in Rotterdam, the Netherlands. The refinery has been modified to enable Neste to produce up to 500,000 tons of SAF per annum. As a result, Neste’s global SAF production capability has increased to 1.5 million tons (around 1.875 billion liters) per annum.

Six months ago I wrote an op-ed in Sweden responding to a column celebrating record levels of air travel in Europe.

My argument then was simple: the problem is not that people want to travel. The problem is that we still travel on fossil fuels.

We don’t need to stop travelling. We need to stop travelling on oil. That requires phasing out fossil fuel subsidies while scaling fossil-free alternatives such as Sustainable Aviation Fuel, e-fuels, and electric aviation.

You can read the English version of that article here: “Should We Really Celebrate Aviation’s Fossil Record?”

Looking back, the debate we are having today is really about the same question: How do we replace fossil fuels fast enough while maintaining the freedom to travel and connect with the world?

Israeli fighter jets on their way to attack Iran in mid-June 2025. Photo credit: IDF Spokesperson’s Unit/Wikimedia Commons

The U.S.-Israel war on Iran has unleashed chaos on the global energy market. Historically, such shocks have triggered a rush to stockpile fossil fuels and backsliding down the energy ladder. On a longer timescale, however, they have pushed world leaders toward greater investment in energy independence.

This latest crisis comes at a unique time for climate diplomacy:  André Corrêa do Lago, following up on commitments made during COP30, has just called for stakeholder contributions to the much anticipated roadmap for a transition away from fossil fuels. It is expected that these contributions will feed directly into the First Conference on Transitioning Away from Fossil Fuels, to be held in Colombia this April.

We’ve seen many energy shocks before but this time a diplomatic infrastructure exists that could guide the world to the only long-term solution to the never-ending energy crises: leaving fossil fuels for good.

Click below to read our full analysis.

Speakers at the WECAN Press Conference “Indigenous Women from the Amazon: Calls for Urgent Action on the Path to COP30” held at COP29 in Baku, 2024. 

Photo Credit: Katherine Quaid / WECAN International