Wizz Air to use jet fuel made from human waste as public pressure grows on emissions

Flights on budget airline Wizz Air could be powered by fuel made from human waste, thanks to an agreement with a sustainable aviation fuel (SAF) company that has announced plans for a world-first production facility.

Bristol firm Firefly Green Fuels announced plans for the refinery at a press conference in London yesterday (11 April). The commercial scale plant in Harwich, Essex, will convert sewage sludge into roughly 43,000 tonnes of SAF per year.

Due for completion in 2029, the facility will supply fuel to Jersey-registered Wizz Air, which previously announced a £5m investment in the company. The airline aims to power 10% of its flights with SAF by 2030. It is also committed to reducing its carbon emissions per passenger kilometre by 25%, by the same deadline.

The airline has invested in its fleet by adding new aircraft and replacing old ones with the Airbus A321neo, which can fly with a blend of up to 50% SAF.

Firefly’s SAF, which will be independently certified, is projected to deliver a 90% reduction in greenhouse gas emissions compared to fossil jet fuel on a life cycle basis. The supplier will provide up to 525,000 tonnes of fuel over 15 years, which could prevent the equivalent of 1.5m tonnes of carbon dioxide emissions.

Yvonne Moynihan, corporate and ESG officer at Wizz Air, said: “Alongside fleet renewal and operational efficiency, SAF plays a crucial role in reducing carbon emissions from aviation. Our investment in Firefly, which has the potential to reduce our lifecycle emissions by 100,000 tonnes CO₂ equivalent per year, underscores our commitment to mainstream the use of SAF in our operations by 2030.

“However, achieving our aspiration requires a significant ramp-up of SAF production and deployment. Therefore, we call on policymakers to address barriers to SAF deployment at scale by incentivising production, providing price support, and embracing additional sustainable feedstocks for biofuel production.”

Speaking in The Guardian, Matt Finch from thinktank Transport & Environment UK said that sewage could also be used to make biomethane, and there was competition for the resource. “What’s the best use of this biomass hasn’t been clarified,” he said. “It’s another conundrum.”

The group also highlighted work by policy consultancy and research group More In Common, which this week showed that the public has “serious concerns” about airlines’ efforts to reduce emissions.

The poll of more than 12,000 respondents found that people are more than six-times more likely to think that airlines should be doing more to reduce their environmental impact (44%) than those who think they do too much (7%). In all surveyed countries – the UK, Germany, France, Spain, Belgium and the Netherlands – more people said they do not trust airlines to tell the truth about their environmental impact than those who say they do trust them.

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