One of the Tories pushing this idea is Tim Yeo who is Chairman of the Commons Environment Committee.
Interestingly Yeo has just been appointed as a non-executive Director of Groupe EuroTunnel, the new French company running the underground railway. He is there as the token Brit to represent the beleagured and disenfranchised UK shareholders, who had their generous perks arbitrarily removed and their share values severely diluted in the recent restructuring.
Unfortunately Yeo has also been picked to promote I presume the 'Green' credentials of EuroTunnel. EuroStar are already using misleading advertising in the UK's national press to suggest that a journey to Paris on one of their trains would be 'carbon neutral'.
However few people know that the Channel Tunnel has two massive refrigeration plants to keep it cool. Trains passing through it act like a pistons and would heat the air to over 54c if not cooled by the huge network of pipes along its 22 mile length.
These refrigeration plants consume the same amount of energy as 260,000 domestic refrigerators. Most of that power is generated by dirty fossil fuel fired power stations in the UK and nuclear power in France. France generates over 82% of its electricity from nuclear power; it tells you on your bill what the breakdown in generation of electricity is in France.
Most power stations have to run 24/7 regardless of demand. The bottom line is that a train to Paris is NOT a very 'green' way to travel.