Aviation is one of the biggest contributors to carbon emissions, yet it has proven challenging to develop innovations to decarbonise the industry. 5% of global warming is attributed to the impact of air travel, and by 2050 experts are predicting it will have consumed 25% of the world’s annual carbon budget.
Emissions from Aviation
Air travel is becoming more accessible, airlines are offering budget flights, and a new generation of travel hungry millennials are taking advantage of this whenever they can. The International Civil Aviation Organization (ICAO) estimates that by next year, emissions from aviation will have inflated by 70% since 2005, and by 2050 they may have increased by 300-700% further. Due to these sobering predictions, the ICAO have made it a global goal to reduce international aviation emissions from 2021.
Other sectors are turning more and more to renewable energies, we are powering our homes and cars with emission reducing alternatives in order to make a significant impact on our carbon footprint, but making this switch in aviation isn’t simple.
Developments are currently underway exploring the feasibility of battery-powered planes. The first of this kind of plane took its maiden flight back in 2015, however it could be another two decades before we see this technology ready to provide commercial air travel, and even then it will likely only support short haul flights.
Electrofuels Offer a Viable Solution
Electrofuels are considered to be the only viable solution to drastically reducing aviation emissions. The plan is to replace jet fuel with electrofuels which combine hydrogen with carbon extracted from CO2. Unfortunately, this method is significantly more expensive and would result in flight prices rising by around 60%.
However, it is seen as a necessary cost for protecting our planet against the impact of rising aviation emissions. Supporters of converting to electrofuels claim that the process would be carbon neutral, and the switch would be relatively simple given that existing aircraft could run on the fuel, meaning that new infrastructure would not have to be developed to support the fuel.
But is this solution truly emissions free? The most common form of acquiring hydrogen is steam reforming, a process that relies on burning fossil fuels to obtain hydrogen from water. Therefore, while burning hydrogen may produce no carbon emissions, the production of it does, making it not technically emissions free.
There are options available for creating hydrogen from renewable sources, but these sources are not seen as a current viable option as the infrastructure is not yet here to support it. Given that reductions to aviation emissions are sought in urgency, it will not wait until these processes are in place.
In addition, CO2 emissions are not the only dangerous emissions to be considered. Aviation heats up the planet through contributing to the amount of contrails, clouds of ice crystals added into the atmosphere from planes flying at high altitudes, which also have a greenhouse effect on the planet. Increasing the amount of hydrogen in our atmosphere has the potential to do severe damage in a similar way to the negative impact CFCs caused, with significant increases in hydrogen would result in higher levels of radiation due to more water being held at higher altitudes. This could cause drastic weather shifts and changes to our seasons.
Once put under the microscope, we can see that our goals for creating emission-free aviation are not possible with the current options being focussed on. We are using fossil fuels to create the hydrogen that is to be burned as electrofuel.
While carbon emissions will be eliminated as an immediate impact of burning fuel during flights, this is offset by the fossil fuels burned to create the fuel. In addition, significant increases to hydrogen in our atmosphere have further negative implications for global warming that are not being considered.
Through a combination of using the electric planes that are currently being developed, and planes powered by electrofuel sourced using renewable energy rather than fossil fuels, emission-free aviation is theoretically possible, but it is not the path we are currently taking in order to reduce emissions.