Sustainable aviation fuel (SAF from waste, biomass, or synthetic e-fuels)

Transport accounts for about a quarter of global energy-related carbon emissions, and it's almost entirely dependent on oil. Cars, trucks, planes, and ships burn fossil fuels that pump CO2 directly into the atmosphere, while our cities and supply chains are designed around this dirty infrastructure.

The challenge isn't just switching to cleaner fuels — it's rebuilding how we move people and goods. Some transport modes like aviation and shipping have no obvious clean alternatives ready today. Others, like personal cars, have solutions that work but need to scale up fast and become affordable for everyone.

This is urgent because transport emissions keep growing as more people get cars and more goods move around the world. We need both better technology and smarter systems that help us travel less wastefully.

Flying is one of the most carbon-intensive things an individual can do, and aviation emissions are growing fast as more people travel. A single long-haul flight can produce more emissions than many people generate in an entire year from other activities.

The problem is that planes need fuel that's lightweight and energy-dense, and they operate in an environment where safety and reliability are absolutely critical. Battery-powered planes might work for short flights, but crossing oceans will likely require new types of fuel that don't exist at scale yet.

Drop-in replacement fuels that work in existing aircraft engines but produce lower lifecycle emissions. These can be made from waste materials, plant biomass, or synthesized using renewable electricity. The challenge is scaling up production and bringing costs down to compete with conventional jet fuel.