The World in 2030

130 The World in 2030
However, relatively little media attention is being paid to
possible alternative fuels for jet engines. It has been received
wisdom that jet engines require from their fuels such a high
density of energy to their weight (and the ability to remain
liquid at the very low temperatures of stratospheric travel) that
there is no practical alternative to carbon-dense kerosene.
Even the Intergovernmental Panel on Climate Change is
certain that there is no alternative to kerosene for jet fuel. In its
report Aviation and the Global Atmosphere, the panel says:
There would not appear to be any practical alternatives
to kerosene-based fuels for commercial jet aircraft
for the next several decades. Reducing sulfur
content of kerosene will reduce SO x
emissions and
sulfate particle formation.
Jet aircraft require fuel with a high energy density,
especially for long-haul flights. Other fuel options,
such as hydrogen, may be viable in the long term,
but would require new aircraft designs and new infrastructure
for supply. 259
Despite such apparent authoritative certainty about the
bleak future for aviation emissions, Time Magazine reported
in 1988 that the Soviet Union had successfully converted a
Tupolev Tu-154 passenger jet modified to burn a mixture of
liquid hydrogen and natural gas. 260
To be fair to the Tyndall Centre, the authors of ‘Living
Within A Carbon Budget’ did recognise that bio-fuels must
play an important role in aviation: