There are four pillars on which business aviation is pinning its hopes of meeting its stated sustainability goals: airframe and engine improvements and optimization; new air traffic control technology and procedures; market-based measures such as the purchase of carbon offset credits; and adoption and use of sustainable aviation fuel (SAF).
While improvements in aircraft design and technologies will ultimately give rise to new methods of flight such as electric and hydrogen propulsion, it is SAF that represents the biggest potential for carbon reductions in the short and mid-term horizons. But that's only if production can be scaled up enough to provide meaningful amounts.
In the U.S. last year, the Biden Administration issued the SAF Grand Challenge to encourage the domestic production of at least three billion gallons of SAF per year by 2030. That represents a dramatic increase over current worldwide production, which is estimated by the Commercial Aviation Alternative Fuels Initiative (CAAFI) to reach approximately 600 million gallons of 100 percent (neat) SAF by the end of 2022. By 2025, that total is expected to more than triple to about two billion gallons based on currently announced projects.
Included in those developments is a $2 billion upgrade to the World Energy facility in Paramount, California, that will see the former petroleum refinery fully converted to sustainable fuel production and give it an output capacity of 340 million gallons a year by 2025. Also in California, Phillips 66 has decided to convert its San Francisco-area refinery from petroleum to renewable fuels. The $850 million project will produce an initial 800 million gallons a year of renewable transportation fuels starting in the first quarter of 2024.
Last week, a consortium of energy industry companies led by SGP BioEnergy announced it partnered with the Panamanian government to launch what will become the world’s largest biofuel production and distribution hub. Dubbed the Golden City Biorefinery, the facility is expected to begin production in 2024 at an output of 60,000 barrels per day initially, expanding to a full capacity of 180,000 barrels daily, or 2.6 billion gallons annually, of sustainable fuels—including SAF—derived from purpose-grown plant oils and waste fats by 2027.
Major renewable fuel producer Neste recently announced it is modifying its Rotterdam, the Netherlands, refinery to better enable SAF production. Currently, the facility is geared mainly toward renewable diesel output, but the nearly $200 million upgrade will give it the option to produce up to 500,000 tonnes of SAF a year as part of the existing capacity. Combined with the company’s ongoing Singapore refinery expansion, Neste will have the capacity to produce 1.5 million tonnes of sustainable aviation fuel annually by the end of 2023.
SAF is approved for use in blends with conventional jet-A at up to 50 percent, but tests by airframers, engine manufacturers, and operators are ongoing to someday enable 100 percent SAF usage. At that level, the fuel can provide lifecycle carbon emission savings of up to 80 percent compared to standard petroleum-based jet-A. Typical blends in use today are 30 percent SAF.
In Europe, proposed as part of the European Commission’s Fit for 55 climate package, the ReFuelEU Aviation regulation would impose a mandate on fuel suppliers to make SAF available at EU airports. While the current supply of SAF is less than 0.1 percent of industry volume worldwide, starting in 2025 the obligation would require 2 percent of the overall aviation fuel supply to consist of SAF, gradually increasing to 63 percent in 2050.
Though some countries such as Norway have already initiated quota mandates on the use of SAF, the European Commission noted that while sustainable aviation fuels have the potential to significantly reduce aircraft emissions, this potential is largely untapped. That is because such fuels represent a very small percentage of total jet-A consumption.
According to business aviation sustainability advisory 4Air, which provides an online SAF-tracking map, the eco-friendly fuel is curently available at a handful of locations in the UK, including Luton, Biggin Hill, and Farnborough airports in the London area, and Hawarden Airport in Chester. In a demonstration last year, Neste-provided SAF was introduced at Gatwick Airport for commercial aircraft use.
Across the English Channel, business aviation operators can find SAF at Paris Le Bourget and Clermont-Ferrand Auvergne airports in France, and at Amsterdam Schiphol Airport. Among the newest locations is Vienna International Airport after Miami-based AEG Fuels recently announced it has partnered with Austrian aviation fuel producer OMV to provide SAF to the airport through the latter’s direct pipeline to the airport.
OMV’s SAF is produced at its Schwechat refinery with used cooking oil collected by local firm Münzer Bioindustrie, which makes the production chain as regional as possible and reduces transport considerations. The two companies will market the fuel for on-demand sales mainly to the general aviation market.
What Is It Made From?
There are seven pathways approved by ASTM International for the production of SAF. But, according to CAAFI executive director Steve Csonka, at least 15 more processes are in the pipeline toward earning approval under ATSM D7566—the specification for jet fuel. The certification of additional production processes will continue to expand SAF supply, he said.
These processes use a wide range of feedstocks, with one of the crucial considerations being that they do not compete with food products. World Energy uses beef tallow with seemingly-endless trains of railcars of the meat waste flowing into its Los Angeles-area facility. Used cooking oils and grease from animals and plants are used by Neste to manufacture its MY Neste fuel.
Earlier this year, bp began co-processing SAF alongside conventional crude oil stocks at its Lingen, Germany refinery. It is the first industrial production facility in the country to use co-processing, which allows up to 5 percent SAF feedstock to be incorporated into the mix.
The company has been advocating for the limit of SAF feedstock co-processing to be increased to as much as 30 percent, according to Laura Bowden, Air bp’s global marketing manager. “We think that will benefit global [SAF] supply given the number of existing refineries today that can, over time, transition from fossil feedstocks through to sustainable feedstocks as well.”
Like many fuel providers, bp is betting heavily on renewable fuels as it estimates conventional oil and gas production is expected to decline by 40 percent from 2019 levels by 2030. In its fourth-quarter earnings call, bp anticipated its investment in five major biofuels projects, including the conversion of up to two refineries.
Other potential sources include municipal solid waste (household garbage); recycled construction materials; agricultural waste, such as corn husks and grain hulls; forestry waste; salt marsh grasses; seaweeds and algae; fermented sugar cane juice; non-food, high oilseed crops, such as camelina, carinata, and jatropha; and even non-recyclable plastics.
Hitting on that last note, London-based renewable fuel startup Clean Planet Energy (CPE) launched a new SAF produced from plastics that would otherwise be simply incinerated or put into landfills. CPE has a production plant already under construction in Teeside in the UK and as many as 11 more under development worldwide.
Through CPE's proprietary process, plastic hydrocarbons are broken down into small chains, which are then upgraded into new products such as SAF and petrochemical feedstocks from which new recyclable plastics can be manufactured. Bp just signed a 10-year offtake agreement for the output of the Teeside facility, which can process 20,000 tonnes of waste plastic a year.
When it comes to feedstocks, even the air itself can be used. A team of Swiss researchers at public research university ETH Zurich announced last year that they have developed technology to produce SAF using nothing but air and sunlight.
Their sun-to-liquid process converts the compounds carbon dioxide (CO2) and water (H2O) into CO and H2 in a specific ratio known as syngas. The final step converts the syngas into liquid hydrocarbons. By tailoring the syngas composition, the researchers were able to produce either drop-in synthetic methanol or kerosene that would be fully compatible with existing infrastructure and fuel supplies.
A spin-off company known as Synhelion has licensed the technology and is building the first industrial facility for the production of carbon-neutral solar fuel in Jülich, Germany, with the start of fuel production anticipated as early as next year.
