6 min readJun 24, 2019

Air Travel x Sustainability — Carbon Emissions & Offset 101

Global warming and the impact to the ecosystem is a growing concern and becoming harder for the general public to ignore. Conversely, transportation is fundamental in today’s global world but it contributes to the detrimental CO2 levels since the current petroleum-based technology consumes a finite resource and gives off pollutants (1). In 2018, domestic and international flights emitted around 895m tonnes of CO2 (MtCO2), which is 2.4% of global energy-related CO2 emissions (2). World Wildlife Foundation asserts that “if the entire aviation sector were a country, it would be one of the top 10 carbon-polluting nations on the planet” (3)

For transportation providers there are two angles which this can be approached: to reduced the amount of CO2 emitted such as through fuel-saving measures whether it is flight planning or engine technology; and to compensate with Carbon Offset programs, the latter which is the focus of this article.

Aircraft & Carbon Emissions

This should be a no-brainer: aircraft engines create carbon emission. There is some research going into electric engines, but they are a long way off so the petroleum-fuel based ones will be around for a while.

The emissions themselves are quite straightforward to calculate. Pilots need consider the flight plan & duration including fuel burn at different altitudes which can be correlated to carbon emissions. For example, CO2 emissions from aviation fuel are 3.15 grams per gram of fuel, which gives CO2 emissions from a Boeing 737–400 of 115 g per passenger km. At a cruising speed of 780 km per hour, this is equivalent to 90 kg CO2 per hour (4). IATA provides a carbon emissions calculator which travelers can use to estimate their impact.

Carbon Offset

The intent of carbon offsetting is to compensate for carbon emissions in one area by applying efforts to reduce carbon footprint in other areas. In a most basic example, it may be “planting a tree” as a natural carbon sink to compensate for the carbon emissions of every kilometer flown.

Carbon offset options are very diverse resulting in a number of marketplaces that exchange carbon emissions on one hand for funds which are applied to an equivalent carbon reducing program on the other, establishing an exchange value being a price per tonne of carbon emissions (currently about $10–40 per tonne CO2).

Airlines typically have a couple different approaches to fund compensation of flight carbon emissions into funding in these marketplaces: either absorb it into the overall airline operating costs (which eventually trickles down to the ticket price), or it can be offered to the passenger for an additional fee (ie: as an ancillary).

Programs and Industry Mandates

Carbon offset is generally guided by the various standards (UN Clean Development Mechanism , Gold Standard (GS), Verified Carbon Standard , the UN-REDD Programme, etc..) and in the airline industry is guided by IATA’s Carbon Offset Program and ICAO’s Emmissions Trading Program,.

ICAO has extended its program and initiated Carbon Offsetting and Reduction Scheme for International Aviation, or CORSIA, an emission mitigation approach for the global airline industry which was agreed by 192 countries in 2016. CORSIA has three implementation phases, beginning 2021. Per CORSIA, all ICAO member states with aeroplane operators conducting international flights are required to monitor, report and verify (MRV) CO2 emissions from these flights every year from 2019. All aeroplane operators with CO2 emissions less than or equal to 10,000 tonnes are exempted from the CORSIA reporting requirements. Participation of countries till 2026 is voluntary.

A brief sample of carbon offset initiatives across the airlines

Most airlines have established some kind of basic carbon offset / climate change program. Typically this can be done through an intermediary (a “voluntary marketplace” or via “emissions trading systems” ) such as QAS who themselves enforce the guidelines on CO2 calculation and also have a portfolio of projects verified against the above standards. It is a good and simple model for airlines that want to demonstrate corporate responsibility / environment responsibility but avoid additional complexity of directly managing the details of the program including project itself & any certification or audits from recognized authorities.

A couple airlines are going above & beyond this and directly managing their own projects, but this adds overhead and the risk is that going alone also may not be considered as compliant.

The following was accurate on/about the time of writing but may have changed since then.

SriLankan sells CO2 offset on their website . They are going through QAS (QAS also supports TAP, Kenya Airways, etc). UL’s credits are sponsoring the Hapugastenne Mini Hydro Project which is referenced by the UN Clean Development Mechanism.
Thai Airways program sponsors Ratchaburi Farms Biogas Project at Nong Bua Farm via the Thai Environmental Institute (TEI) . The project is also referenced by the UN Clean Development Mechanism. TG is also referenced by QAS (but QAS is not promoted on the TG website).
Cathay Pacific also manages its own projects.
JetStar’s Fly Carbon Neutral Program has been certified under the Australian Government’s National Carbon Offset Standard (NCOS)
Qantas is managing its own CO2 emissions scheme & projects notably with Qantas Future Planet. The one drawback is that at the time of writing, apparently the projects themselves do not have international accreditation.
The Virgin Earth Challenge is another independent program.
United has been quite forward thinking in its carbon offset program, with a type of “environmentally innovative” approach UA are now working with Sustainable Travel International (STI) who themselves fund several separate carbon reduction programs which are vetted by international organizations.
A good in depth analysis of the British Airways voluntary carbon offset scheme was done int ICAO’s “vets_report.pdf” . BA launched the program in September 2005 and it operates primarily via its website. Passengers are able to offset the CO2 emissions created during their flights by making a voluntary contribution to an organization called Climate Care. The voluntary contribution is calculated on an emissions cost of approximately £7.50 per tCO2, using actual fuel consumption and load factors from the British Airways’ aircraft fleet. This translates to a contribution of £5.00 per passenger on a return flight from London to Madrid and £13.30 for a return flight from London to Johannesburg. On longer routes, such as a return flight between London and Sydney, the contribution is £28.83. Climate Care’s work is scrutinised by an Environmental Steering Committee, which includes environmentalists and NGOs including WWF and Forum for the Future. Note: it seems BA’s program has changed since then (https://www.britishairways.com/en-gb/information/about-ba/csr/corporate-responsibility ), apparently working with PURE as a 3rd party) — Some additional background here: British Airways sets off towards its destination of becoming the world’s most responsible airline

Carbon Offset & Innovation

The post wouldn’t be complete without mentioning how a few startups are trying to tackle the problem:

ClimeWorks captures CO2 from air with the world’s first commercial carbon removal technology to supply to customers and to unlock a negative emissions future.
Syngenera is helping with the acquisition and management of forest concessions, cultivation of sustainable biomass, and innovation to bridge between corporate customers and local communities in Southeast Asia
There are a couple initiatives for tracking carbon credits on the blockchain-based including: Veridium Labs (Hong Kong), Energy-Blockchain Labs and IBM,

How it comes together

As CORSIA rolls out, there will likely be an increased pressure on airlines in working towards improving their contribution towards reducing their carbon footprint. Yet establishing a standard and ensuring airlines are compliant are two different things… a Financial Times article points out that “this is where the airline carbon-offset business falls down. While there are organisations that validate particular projects, no one is validating airlines’ entire programmes”.

For airlines, the easiest approach is through and external carbon offset program provider, for example STI or QAS who typically will help both calculate & audit emissions estimations as well as help broker with an appropriate trading marketplace and specific projects. That said, those airlines which have demonstrated the additional commitment in establishing and running their own carbon-offset programs are also good examples to emulate.

Altogether it is progressing, but what is left to be seen is whether it will improve at a rate which can eventually counterbalance the existing carbon burden and eventually bring air travel to a point of becoming carbon neutral.

References

You can find this and more on TripSimian.Solutions