In the guide below, we discuss whether sustainable air travel is possible.
We outline the current impact of air travel on the environment and sustainability, how air travel might get more sustainable, potential challenges in improving sustainability for air travel, & other relevant aspects of sustainable air travel.
Summary – Is Sustainable Air Travel Possible?
How To Assess & Measure Sustainability
What sustainability is, and the different pillars of sustainability, are two things we have discussed elsewhere on this site, so, we haven’t gone into detail about these topics in the guide below.
What’s worth mentioning though is that assessing and measuring sustainability comes down to the indicators used, and what the goals and benchmarks for sustainability might be.
Impact Of Air Travel On Sustainability
Reducing carbon emissions from air travel is a common indicator and goal proposed by several groups.
However, there are other sustainability indicators that can be considered for air travel too.
In the guide below, we outline the different ways air travel may impact sustainability and the environment, and the different sustainability indicators that might be involved.
Is Sustainable Air Travel Possible?
It might be accurate to say that it’s possible to make air travel more sustainable in the future than it is now.
As one example, the carbon footprint of air travel might be able to be reduced.
However, it might also be accurate to say that making air travel more sustainable has several challenges.
Making air travel more sustainable may also have some limitations, and, some sustainable solutions may still be years or decades away at this point in time.
For example, some reports indicate that no technology or solutions are going to replace carbon based jet travel before 2030, and, introducing new planes like hydrogen hybrid or electric planes on a commercial level might be even further away than that.
In the guide below, we outline several ways that air travel might become more sustainable, along with some of the potential challenges.
Importance Of Sustainability In Aviation
The importance of sustainability in aviation comes from both the importance of the industry to society as a whole (in terms of what it allows us to do, and how it contributes to the economy), and, also the impact of aviation activities on different aspects of sustainability.
From a practical perspective, the aviation industry facilitates travel, transport and freight.
From an economic perspective, the aviation industry contributes a significant amount of value to the world economy, and employs a lot of people.
From an environmental perspective, when specifically looking at the carbon footprint of the aviation industry, it’s % share of global carbon emissions compared to other industries, and the carbon intensity or air travel can be considered:
– According to atag.org: ‘The global aviation industry produces around 2.1% of all human-induced carbon dioxide (CO2) emissions’
– According to one report, air travel is one of the most carbon intensive activities for individuals
Having said that though, the aviation industry impacts sustainability in more ways than just carbon emissions.
How Does Air Travel Affect The Environment & Sustainable Resource Use?
Air travel has an impact on the environment and sustainable resource use at different lifecycle stages, and also across different indicators.
For example, different jet fuels involve sourcing from a feedstock (of which there can be many different ones), converting the feedstock into fuel, blending the final fuel product (like for example blending 50% biofuel, and 50% conventional jet fuel), and then using the fuel in an aircraft.
Additionally, air travel doesn’t only have a carbon footprint, but can also use resources like energy, water, and land, produce air pollutants, may involve mining, and may also result in deforestation.
To explain some of these points further:
– Fuels & Feedstocks
Different fuel types have different feedstocks, and have different stages over their lifecycle.
Petroleum based feedstock (made from hydrocarbons) essentially involves taking carbon out of the ground, converting it to jet fuel (a type of kerosene), and that carbon is then burnt and emitted in the air during air travel.
Biofuels on the other hand come from a range of different renewable or sustainable feedstocks.
Plant based feedstocks for example absorb carbon as biomass, are converted into fuel, and then release their absorbed carbon when they are burnt during air travel.
Sourcing fossil fuels may involve mining.
Sourcing some types of biofuels may involve competing with other land uses, using different types of land, using different inputs and resources (like water, fertilizer, pesticides), and may involve deforestation if trees are cleared for land conversion.
– Different Types Of Energy Used During Production
Producing airplane fuels requires using energy to convert feedstock into fuel.
Using renewable energy during production may lower the carbon footprint of some fuels
– The Airplane Itself
The airplane itself also impacts sustainability and has an environmental impact.
More efficient airplanes use less fuel per mile, and per passenger mile travelled (when taking into consideration the carrying capacity of the aircraft)
– Different Environmental Indicators
Aside from total carbon emissions and the carbon intensity of air travel, other potential environmental effects and sustainability considerations of air travel might include:
– Whether the feedstock is renewable or sustainable
– Resources used for some types of biofuel feedstock (land use, water use, fertilizers and pesticides, and so on)
– Impact of mining for fossil fuels for conventional jet fuels
– Environmental effects of growing some types of biomass (deforestation, water and soil pollution, etc)
– Energy, water and other resources used to convert feedstock to fuel, and the environmental effects of conversion too
– Emissions from energy used during production (renewable energy vs fossil fuel energy)
– Greenhouse gas emissions during air travel (when burning fuel)
– Air pollutants released during air travel (in contrast to GHGs)
Sustainable Aviation Fuel
Sustainable aviation fuel, or SAF, is something we’ve written about in this guide.
It is a type of fuel that has been developed (and is still being developed) with one of the main goals being to reduce carbon emissions throughout the lifecycle of the fuel.
Cost, limited supply, and scaling of infrastructure are some of the current problems limiting wider adoption of SAFs.
Sustainable aircrafts are more of a concept or an idea at the moment.
Similar to sustainable aviation fuel, a sustainable aircraft might be an aircraft emits less carbon emissions during operation.
Sustainable aircrafts might:
– Have a different design to be more fuel efficient
– Be made of lighter materials to be more fuel efficient
– Be more fuel efficient per mile, or per passenger mile (which takes into account airplane capacity too)
– Use different fuels to produce less emissions
– Have other features that make it more sustainable in some way
Eco-Friendly Planes Of The Future
Other than conventional jet fuel planes, or planes running blended fuels, some other types of planes have been suggested as concept eco friendly planes of the future.
These planes mainly include:
– Hydrogen planes, and hydrogen hybrid planes
– Electric planes
These planes can have several challenges and potential limitations though, such as:
– Limited flying range
– Limited size to carry passengers (and freight)
– Batteries for electric planes might be too large and too heavy
– It can be difficult to beat the energy density of conventional jet fuel with alternative energy sources (popsci.com discusses the challenges with energy density of different fuels in their resourc)
– Needing to attract investment for development, infrastructure, scaling and commercialization
– It may be decades until some new planes and technology reach commercial scaling levels
– Overall, aviation has some challenges that cars and stationary power plants don’t because of the nature of having planes that have to move lots of people in the air.
What Other Options Are There For More Sustainable Air Travel?
– More fuel efficient planes (per mile, and per passenger mile) – design of the plane, plane materials, plane capacity, plane fuel, plane routes, and other factors may be changed to make plans more efficient
– Policy changes, tax credits, public-private partnerships, and other options that might help with encouraging investment in technology and infrastructure, scaling to commercialisation, and increasing cost competitiveness of sustainable technology
How Can Renewable Energy Be Used In Air Travel?
Renewable energy might mainly be used:
– During production processes, such as for the conversion of feedstock into fuel (and for other production processes)
– For electric planes, and planes that can convert renewable energy into fuel such as hydrogen. Although, these planes appear aren’t used on a commercial scale yet – they are more concept planes at this stage, or test/experimental planes
What Are The Most Sustainable Airlines?
Without naming specific airlines, sustainable airlines might communicate transparently to their customers, and show evidence of the how and why they are more sustainable.
For example, an airline might show evidence of using a certain fuel that produces less emissions and less air pollutants per passenger mile travelled, over the lifecycle of fuel, and not just during flights.
Another example is that they might use more fuel efficient plane models, or, they might schedule some more fuel efficient routes.
Something to be aware of with sustainable air travel is cost.
If costs of more sustainable fuel for example are passed onto the customer, this may be an issue for those who need access to more affordable flights, or budget level flights.
Another thing to be aware of is practicality.
If short haul trips are deemed less sustainable, but people need these trips for critical things such as work, family, or something else, this can be an issue.
2. Various ‘Better Meets Reality’ resources