How to decarbonise commercial ports

Ports, essen­tial infra­struc­tures for mar­itime freight, have com­mit­ted them­selves to decar­bon­i­sa­tion. They are areas which house numer­ous activ­i­ties – indus­try, trans­port, tourism – in direct con­tact with a city, and it is this prox­im­i­ty to the inhab­i­tants which has for a long time pushed the sec­tor to work towards the reduc­tion of noise, odour, and atmos­pher­ic pol­lu­tion. But today pol­i­cy-mak­ers are increas­ing­ly con­cerned by a more seri­ous type of pol­lu­tion: green­house gas emis­sions (GHG). 

“Europe is the most advanced region in the world when it comes to the ener­gy tran­si­tion of ports,” says César Ducruet, CNRS geo­g­ra­ph­er at the Economix lab­o­ra­to­ry of the Uni­ver­si­ty of Paris Nan­terre. Numer­ous projects are con­cen­trat­ed in the North-West, but they are rar­er in the Mediter­ranean. In France, only ports with more than 250 employ­ees are oblig­ed to assess their car­bon foot­print. Although oth­ers are inte­grat­ing the eco­log­i­cal tran­si­tion into their strate­gic projects¹. 

“Ports can impose con­straints on ships. After Sep­tem­ber 11^th 2001, the Unit­ed States imposed impor­tant secu­ri­ty mea­sures that were sub­se­quent­ly dis­sem­i­nat­ed through­out the world,” recalls Gaëlle Guéguen-Hal­louët, pro­fes­sor of pub­lic law at the Uni­ver­si­ty of West­ern Brit­tany. “We can expect to see the same thing hap­pen with decar­bon­i­sa­tion: for some years now, we have seen that port author­i­ties want to be dri­ving forces behind the eco­log­i­cal tran­si­tion.” The Inter­na­tion­al Asso­ci­a­tion of Ports and Har­bours (IAPH), for exam­ple, set up an envi­ron­men­tal indi­ca­tor (the Envi­ron­men­tal Ship Index) in 2011 to eval­u­ate the emis­sions of ships. Depend­ing on a thresh­old defined by each port, ships that pol­lute less can ben­e­fit from reduc­tions in port dues. Although mem­ber­ship of the scheme is option­al, near­ly 7,000 ships cur­rent­ly take part.

It is dif­fi­cult to pre­cise­ly mea­sure GHG emis­sions from ports. The geo­graph­i­cal con­tours of the port area vary accord­ing to esti­mates, whether at sea or on land, and indus­tri­al activ­i­ties (not relat­ed to freight) are some­times includ­ed. For the Inter­na­tion­al Mar­itime Organ­i­sa­tion (IMO), the port area begins where the ship reduces speed in open sea to enter the approach phase². GHGs are emit­ted dur­ing manoeu­vres by ships, load­ing and unload­ing of goods at berth, var­i­ous port activ­i­ties, land trans­port, etc. A recent analy­sis by the Trans­port & Envi­ron­ment organ­i­sa­tion³ esti­mates that the port of Rot­ter­dam, the most pol­lut­ing in Europe, emits 13.7 mil­lion tonnes (Mt) of CO2 per year, fol­lowed by Antwerp (7.4 Mt of CO2) and Ham­burg (4.7 Mt of CO2) (com­pared with one bil­lion tonnes for all mar­itime freight). 

The main cul­prits? Ships. They emit 10 times more GHGs than the port activ­i­ties them­selves⁴. It should be not­ed, how­ev­er, that emis­sions from ships in port areas only rep­re­sent a few per­cent of their total emis­sions⁵. For some ships, such as chem­i­cal tankers and oil tankers, how­ev­er, this share is high­er and can exceed 20% of their total emis­sions. “Ships account for 60% of the port’s emis­sions, fol­lowed by land trans­port (30%) and the ter­mi­nal (10%),” says César Ducruet.

Ships account for 60% of a port’s emis­sions, fol­lowed by land trans­port (30%) and the ter­mi­nal (10%).

What is the solu­tion? “The ide­al port would imple­ment a whole range of reduc­tion mea­sures,” sum­maris­es César Ducruet. On the quay­side, aux­il­iary engines burn fuel to gen­er­ate the elec­tric­i­ty need­ed on board the ship: to cool the con­tain­ers, or to acti­vate the pumps and cranes for load­ing goods. This is the most sig­nif­i­cant emis­sion item (about half of the emis­sions for the 4 ports stud­ied⁶): it rep­re­sents 11% of glob­al mar­itime emis­sions⁷. The elec­tri­cal con­nec­tion of ships at berth – avail­able in the port of Stock­holm since the 1980s – allows the aux­il­iary engines to be switched off. Emis­sions are then direct­ly linked to the method of elec­tric­i­ty pro­duc­tion. Sev­er­al reg­u­la­tions are there­fore push­ing the ports to install them: the Euro­pean Union in par­tic­u­lar is impos­ing the instal­la­tion of shore-side con­nec­tions by 2025. In 2020, 66 ports in 16 dif­fer­ent coun­tries were already offer­ing this ser­vice⁸, includ­ing 8 major ports⁹. 

The trans­fer of goods is anoth­er major mech­a­nism for decar­bon­i­sa­tion. Sec­ondary ships trans­port­ing goods from inter­na­tion­al to domes­tic ports, han­dling equip­ment and trucks are major sources of GHG emis­sions¹⁰. The use of LNG for han­dling equip­ment, for exam­ple, offers the oppor­tu­ni­ty to reduce port GHG emis­sions by 25%¹¹. Elec­tri­fi­ca­tion of car­go han­dling equip­ment could reduce CO2 emis­sions from US ports by 27–45% by 2050¹². The elec­tri­fi­ca­tion of trains and heavy goods vehi­cles offers a poten­tial reduc­tion of 17 to 35% by the same date. “In Europe, 75% of goods are trans­port­ed by road, and for Le Havre this fig­ure ris­es to 90%,” says César Ducruet. There is there­fore a major poten­tial for decarbonisation.

The final avenue is through organ­i­sa­tion­al and tech­ni­cal mea­sures. The cal­cu­la­tion is sim­ple: by reduc­ing the time spent at berth, emis­sions from ships’ aux­il­iary engines are direct­ly reduced. In Syd­ney Har­bour, oil and chem­i­cal tankers spend an aver­age of 32 to 52 hours in port¹³. Improv­ing pro­duc­tiv­i­ty, reduc­ing wait­ing time for loading/unloading, improv­ing traf­fic flow, and mak­ing cus­toms clear­ance pro­ce­dures more effi­cient are all effec­tive and inex­pen­sive mea­sures that should be imple­ment­ed¹⁴. Var­i­ous stud­ies esti­mate their GHG reduc­tion poten­tial at 10–20%. Oth­er tech­ni­cal mea­sures are also rec­om­mend­ed, such as auto­mat­ed dock­ing sys­tems, the use of LEDs to illu­mi­nate the ter­mi­nal (the sec­ond largest con­sumer of ener­gy) or the opti­mi­sa­tion of the ter­mi­nal’s sur­face area, which could reduce GHGs by around 70%¹⁵.

Unlike oth­er mar­itime freight seg­ments, there is no sin­gle solu­tion for decar­bon­is­ing ports. “The vary­ing con­di­tions expe­ri­enced by each port sug­gest that emis­sion reduc­tion mea­sures must be tai­lored to each port,” write the authors of a study pub­lished in 2017¹⁶. In a sur­vey of var­i­ous port oper­a­tors, the IMO high­lights the impor­tance of reg­u­la­tions and stan­dards as a mech­a­nism for deci­sion mak­ers to take action¹⁷. “The IMO pro­duces a large part of the inter­na­tion­al reg­u­la­tions gov­ern­ing mar­itime trans­port, but ports are not only linked to mar­itime trans­port,” adds Gaëlle Guéguen-Hal­louët. “The diver­si­ty of the par­ties involved in port man­age­ment, and the vari­ety of their con­cerns, is a major oper­a­tional bar­ri­er. I think that the Euro­pean Union has an essen­tial role to play: Euro­pean law is by its very nature bind­ing for mem­ber coun­tries,” he con­cludes. If it is decid­ed at a Euro­pean lev­el that only low-emis­sion ships are allowed to enter Euro­pean ports, this oblig­a­tion will apply to ships from fleets all over the world.

Anaïs Marechal