Firefly //
A new route to SAF
We’re pioneering a new and exciting route to SAF that repurposes an abundant, highly sustainable waste material – sewage.

By reusing sewage we are helping to lessen the environmental impact of aviation whilst supporting global biodiversity and public health.
The Firefly Solution
Our process, hydrothermal liquefaction (HTL), uses a combination of high pressure and heat at lower energy levels, and is good for processing wet wastes. Using HTL we turn sewage into crude oil and biochar.
Biochar is a good option for carbon sequestration in construction or in agriculture, where it can also be used as a soil improver.
The crude oil, meanwhile, will be processed into sustainable aviation fuel (SAF), via proprietary processes derived from those used to synthesise fossil-derived jet fuels.
Our proposition at a glance
Economics
- HTL (Hydrothermal liquefaction) is a very energy efficient way to create biocrude.
- The simplicity of our process brings production costs down, potentially allowing our SAF to be competitively priced.
- Our focus is on using sewage sludge, but our process is appropriate for use with other wet biogenic materials.
- Our solution is widely applicable in multiple locations around the world, even areas where there are limited other options for generating sustainable energy.
Sustainability
- Our LCA (Life Cycle Analysis) was completed by independent specialists at Cranfield University, who found carbon emissions to be over 90% lower than standard fossil jet fuel.
- The carbon intensity of our process is just 7.97 g CO²e/MJ
- Biochar produced during our process is excellent for carbon sequestration and could be used in construction or agriculture.
- Our feedstock is a completely biogenic waste material – our process creates new value, transforming it from unwanted waste to valuable resource.
Scalability
- Our process can be implemented anywhere in the world where human waste is processed.
- The global need for SAF far outstrips supply; there is a huge market for SAF and our simple, energy efficient process will allow us to produce it at a very competitive price.
- National and international mandates for SAF uptake provide market stability and an economic incentive for future upscaling of production.