Another fun back of the envelope calculation

Almost impossible to get accurate numbers here, so I will make some wild approximations and hope the errors cancel out.

About 500,000,000 vehicles worldwide

Average use of gasoline about 1L/hr

Amount of CO2 released ~ 100L/L gasoline *

Total 5 x 10^11 L/hour

Area of Chunnel (all three tunnels) ~ 100 sqM

So, IF (not really possible) all the gas moved through the tunnel, it would do so at about 5 x 10^3 kM/hr

I take no responsibility for errors in the assumptions or calculations!

* See a good analysis by Dr. Barrans http://www.newton.dep.anl.gov/askasci/chem99/chem99583.htm

I have used just hot CO2 and ignored loss of O2  and temperature effects

Mike's answer was characteristically excellent, but I shall try an opposite tack: statistically one should expect (and it would be consistent with human nature and politics) that probably half the exhausts would blow from each side, so the resultant wind would amount to about zero.

Things might get a bit niffy in the tunnel of course, and I hope that the exhaust fans would be pretty good. If they failed, the tunnel soon would go pop!

But compare either my figure or Mike's with the gas output (largely steam or CO2) of a modest-sized gas-rich volcano.  Think of that as a source of power...

Think of a few implications...

Just thinking...

...

Jon