Wounded by Covid, aviation confronts its emissions challenge

Few sec­tors have been hard­er hit by the pan­dem­ic than avi­a­tion. But as vac­cine roll­outs help ease restric­tions and the indus­try plots a route back to prof­itabil­i­ty, it’s fac­ing anoth­er exis­ten­tial threat: the pres­sure to decar­bonise. 

Today, avi­a­tion con­tributes around 2–3% of glob­al green­house gas emis­sions, but is on course to become the sec­ond-high­est emit­ter in 2050 as oth­er sec­tors reduce their impact. Due to the tech­no­log­i­cal leaps required to reduce sec­tor emis­sions, experts say the ground­work must begin now if the world is to meet the tar­gets agreed in the Paris Cli­mate Change accord. 

Giv­en the tur­moil of the last 18 months, the tim­ing couldn’t be worse. But despite the adver­si­ty, the indus­try is respond­ing. Last Sep­tem­ber air­line alliance oneworld announced that all 13 of its mem­bers, includ­ing British Air­ways, have com­mit­ted to net-zero emis­sions by 2050. 

Gov­ern­ments are also out­lin­ing their ambi­tions for the sec­tor. The UK is one of the biggest exporters of aero­space prod­ucts and ser­vices glob­al­ly. This month the gov­ern­ment, as part of its £125m “Jet Zero” ambi­tion to deliv­er the first zero-emis­sion trip across the Atlantic, launched a strat­e­gy con­sul­ta­tion on how Britain can become a van­guard of progress. 

Technologies for change

“There’s no sil­ver bul­let or sin­gle tech­nol­o­gy that we believe can achieve car­bon neu­tral­i­ty by 2050,” warns Bram Peer­lings, con­sul­tant for sus­tain­able avi­a­tion at Nether­lands-based research cen­tre NLR and co-author of a report on decar­bon­is­ing avi­a­tion, called “Des­ti­na­tion 2050”.

Still, NLR believes that dif­fer­ent solu­tions have dif­fer­ent time­lines: “oper­a­tional improve­ments can be imple­ment­ed fair­ly quick­ly, where­as large-scale use of sus­tain­able fuels and espe­cial­ly the imple­men­ta­tion of rad­i­cal tech­nol­o­gy will take longer, as time is required for fur­ther devel­op­ment and com­mer­cial­i­sa­tion”, Peer­lings says.

The report states that 92% of indus­try-asso­ci­at­ed CO2 emis­sions from flights depart­ing from the EU and UK can be reduced in-sec­tor. The remain­der will require car­bon cap­ture and for­est plant­i­ng. 

In some ways, the pan­dem­ic has expe­dit­ed improve­ments in emis­sions reduc­tions already. KLM Roy­al Dutch Air­lines and British Air­ways both retired ear­ly age­ing Boe­ing 747s for more effi­cient car­ri­ers. It’s esti­mat­ed that next-gen­er­a­tion mod­els of air­craft, such as the Air­bus A320neo, improve fuel effi­cien­cy by around 20% com­pared to their pre­de­ces­sors. 

But it will take more than a fleet upgrade to get the indus­try to where it needs to be. In the short term, replac­ing kerosene or blend­ing it with sus­tain­able avi­a­tion fuel – known as SAF – is one of the most promis­ing. Made from renew­able feed­stocks such as waste oils and agri­cul­tur­al residue, SAF can low­er car­bon emis­sions by 70% com­pared to con­ven­tion­al jet fuel.

SAF is cur­rent­ly two to three times as expen­sive as con­ven­tion­al jet fuel, and pro­duc­tion is only 0.05% of total EU jet fuel con­sump­tion. To incen­tivise its devel­op­ment, this month the Euro­pean Com­mis­sion pro­posed a pro­gres­sive tax on pol­lut­ing jet fuel, which was pre­vi­ous­ly exempt, as well as increas­ing min­i­mum SAF blends to 2%, ris­ing to 5% in 2030 and 63% in 2050. The World Eco­nom­ic Forum’s Clean Skies for Tomor­row ini­tia­tive also hopes to boost SAF use with a  cer­tifi­cate pro­gramme launched in June that enables com­pa­nies to pay a pre­mi­um for the fuel when fly­ing, which can then be used in their Scope 3 car­bon emis­sions account­ing.

SAF needs no new infra­struc­ture or equip­ment invest­ment, unlike elec­tric and hydro­gen-pow­ered planes, which require entire­ly new engi­neer­ing. Despite the dif­fi­cul­ty, it’s look­ing like short­er com­mer­cial routes could be using elec­tric planes with­in the decade. In a notable move, Unit­ed Air­lines in July announced it would buy 100 19-seat elec­tric planes from Swedish start-up Heart Aero­space, on con­di­tion they meet safe­ty, busi­ness and oper­at­ing require­ments. The zero emis­sion planes can fly cus­tomers up to 250 miles and use elec­tric motors instead of jet engines, and bat­ter­ies instead of jet fuel. They’re expect­ed to be oper­a­tional in 2026.

It’s unlike­ly that bat­tery pow­er would ever be viable for big­ger air­craft, though, due to the weight of the bat­ter­ies. But there will like­ly be lev­els of “hybridi­s­a­tion” along the way, accord­ing to Mark Howard, head of com­mer­cial strat­e­gy for Fly­Ze­ro, a £15m UK gov­ern­ment-fund­ed ini­tia­tive deliv­ered by the Aero­space Tech­nol­o­gy Insti­tute (ATI). Its remit is to out­line a future decar­bon­i­sa­tion frame­work for the sec­tor. 

The Des­ti­na­tion 2050 report cal­cu­lates that range and capac­i­ty-opti­mised hybrid-elec­tric air­craft could reduce CO2 emis­sions by 50% for small­er, region­al-class air­craft.

For larg­er car­ri­ers, green hydro­gen or ammo­nia-pow­ered planes are cur­rent­ly con­sid­ered the front-run­ning tech­nol­o­gy. How­ev­er, these aren’t expect­ed before 2035 due to due to the nec­es­sary tech­no­log­i­cal and sup­ply chain devel­op­ment.  

Howard, who has worked for Air­bus for 35 years, says FlyZero’s cur­rent think­ing is that liq­uid cryo­genic hydro­gen – which is minus 253 degrees Cel­sius – will be need­ed.

“It’s not a sim­ple swap out of tech­nol­o­gy, we have to almost start again with the air­craft design,” he explains. Air­bus last year revealed three hydro­gen-pow­ered con­cept planes, all tak­ing dif­fer­ent engi­neer­ing approach­es.  

Commercial viability 

Any new tech­nol­o­gy adopt­ed will need to be com­mer­cialised and – impor­tant­ly — uni­ver­sal­ly trust­ed.

“Every­one is used to oper­at­ing with kerosene-pow­ered planes. There needs to be a lev­el of tech­no­log­i­cal matu­ri­ty and dri­ving costs down before equip­ment man­u­fac­tur­ers, air­lines – and the pub­lic – will accept change, both tech­no­log­i­cal­ly and cost-wise, which is why we need to act now to address the car­bon chal­lenge,” says Howard. 

The glob­al avi­a­tion indus­try is expect­ed to be worth around £4tn by 2050. Yet in April the UK indus­try raised alarm after the ATI, which allo­cates gov­ern­ment mon­ey to the sec­tor, was forced to sus­pend its fund­ing pro­gramme for 2021.

With so much invest­ment and trans­for­ma­tion required, a key ques­tion remains: will it make fly­ing more expen­sive for the mass­es? “That’s what our mod­el­ling cur­rent­ly fore­sees,” say Peer­lings. “Though it’s pos­si­ble com­pa­nies might decide to inter­nalise some of those costs.”

Ulti­mate­ly, to achieve these ambi­tious goals, gov­ern­ments must cre­ate pol­i­cy and pro­vide fund­ing streams to incen­tivise and sup­port the nec­es­sary invest­ments, agree Peer­lings and Howard.  

“By not doing this gov­ern­ments risk miss­ing an oppor­tu­ni­ty to cap­i­talise on the sus­tain­able avi­a­tion mar­ket; it’s a glob­al prob­lem and a glob­al indus­try, so there is a race to com­pete,” says Howard.