Aviation and marine transport accounted for around 7 Mb/d and 5 Mb/d of oil consumption in 2018 respectively. Demand for these services increases over the Outlook in both Rapid and BAU: growth in shipping is driven by increased levels of trade; whilst expansion in air-travel is underpinned by growing prosperity, especially in emerging economies. In Net Zero, the growth in air travel by 2050 is around 10% lower than in BAU, reflecting in part a shift in societal preferences to use high-speed rail as an alternative to air travel in China and much of the OECD. Similarly, increasing preference for the consumption of locally-produced goods and reduction in oil trade in Net Zero contributes to reduced shipping demand by around a third by 2050 relative to BAU.
In Rapid, liquids demand from aviation remains relatively stable at around 7 Mb/d over the course of the Outlook, as efficiency improves by around 35%, largely offsetting additional demand for air travel. In Net Zero, these efficiency savings plus reduced appetite for flying in some markets means liquids demand from aviation peaks in the early 2030s and declines to a little below 2018 levels by 2050. In contrast, liquids demand continues to grow throughout the Outlook in BAU, reaching 10 Mb/d by 2050.
Biofuels play a critical role in decarbonizing the aviation sector, since neither batteries nor hydrogen are able to deliver the necessary energy density required for aviation. The share of biofuels in jet-fuel increases from less than 1% in 2018 to around 30% by 2050 in Rapid and to nearly 60% in Net Zero. In contrast, there is minimal growth in the share of biofuels in BAU.
Unlike aviation, the fuel mix in the shipping sector is able to diversify into hydrogen (either as ammonia or in liquid form) and LNG, as well as biofuels. In Rapid and Net Zero, non-fossil fuels account for 40% and 85% of marine transport fuel by 2050 respectively, with more than half of that coming from hydrogen. Conversely, under BAU, marine demand for oil increases slightly by 2050, with natural gas increasing its share of the sector fuel mix to just under 15% and non-fossil fuels accounting for just 1%.