Earlier this year, a long-distance flight was performed by Qantas, using 10% biofuel. 150 acres of mustard was required for this flight. ow.ly/byRP30lz8td
Also, suppose that roughly 1/4 of all flights are long-distance & that short-distance flights require 75% less fuel than long-distance.
Worldwide, about 39 million flights are performed annually (growing approx. 5% per year).
A biofuel-based aviation system would require 39 million x 260 ha = 101.4 million square kilometers.
So the biojetfuel would require six times the global arable land area.
That is, 68% of the total land area.
Big question though:
How can a fuel demand equal to the energy we can get from mustard fields covering 68% of land NOT compete with food & agriculture, in one or the other way?
And even if it were possible, emissions wouldn't decrease enough, because biofuels produce emissions, too.
It's still uncertain whether they ever will gain substantial commercial importance, but if they do, it will take at least 10-15 years from now.
In society as a whole, emissions will have to decrease rapidly over the next 30 years - about 7% annually, to have a chance to reach the 2 degree target.
And, as I have shown in another thread, aviation will account for as much as 20% of global emissions by 2030 - if aviation continues to grow as much as expected.
We need emissions cuts faster than light.
Aviation, too, has to cut emissions rapidly.
And the so-called "sustainable aviation" dream won't save us.
We have to start flying less - in fact, much less.
That means fewer flights worldwide, instead of MORE flights - the current trajectory.
Well, some people will, but most people won't.
As long as flying doesn't get more expensive, that is, continues to be free from any form of tax, not much will happen.
The longer we postpone decisions to put a sufficiently high price on carbon,
the more greenhouse gases emitted to the atmosphere.
And the bleaker our children's future.