The largest potential efficiency gains can be obtained by completely redesigning aircraft. Considering the long lead times and investment required, such measures are unlikely to be commercialised by 2030. However, “clean sheet” wing and tube aircraft have the potential to reduce fuel burn by 40% (Kharina, 2017).

In addition to research and trials of new, more efficient aircraft designs, adoption of alternative, low-carbon jet fuels will be needed to reduce CO2 emissions. Technology and scale-up barriers in producing such fuels can be best addressed through direct support from governments, incentives and standards.

Nearer term solutions, such as improving flight routing systems and switching to hydrogen and/or electricity during taxiing, can also improve the overall efficiency of the sector.

Shortening flight distances through better routing

Considerable fuel is wasted due to inefficient routing. While providing the same service, better flight routing could limit inefficient passenger activity growth and cut consumption by as much as 10%.

Innovation gaps in buildings

Transitioning to high-performance buildings by 2030 will require technical innovation to meet the energy needs of a variety of building types in multiple regions. Innovation is particularly needed to raise investment returns for high-performance building envelope technologies, taking energy prices, labour costs and the nature of the building design or retrofits into account.

Building envelopes

Boosting construction of high-performance buildings by 2030 will require innovative technical solutions and business models to meet the energy needs of a variety of building types in multiple regions. Innovation is also needed to improve investment returns for high-performance building technologies, taking energy prices, labour costs and the nature of the building design or retrofits into account.

Advanced windows

Windows are estimated to be responsible for 5-10% of total energy consumed in buildings – and even higher for certain buildings (e.g. with all-glass facades). Highly insulated windows have great potential to reduce energy consumption in new buildings and in structural retrofits.

Maximising/minimising solar gains (depending on the region) can significantly reduce heating/cooling demand, especially in buildings with considerable glass. Optimising visible light transmittance can reduce lighting energy demand.

Advanced air flow, air sealing and ventilation controls

Airtightness is a strong determinant of energy demand in buildings. In cold climates, exfiltration through the building envelope accounts for a significant share of a building's thermal losses.

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