There's also a green argument for opting for a high speed (rather than very
high speed) rail line.
A survey carried out in 2004 in the UK, found that the energy used per seat on trains travelling at a maximum 225kph (140mph) between London and Edinburgh (400 miles) would be 30kWh per seat. Increase the maximum speed to 350kph (220mph) and the energy use would increase to 57kWh per seat. (Trains between London and Edinburgh in reality run at a maximum speed of 200kmh (125mph).)
So unless your ultra-high speed line is running on power generated by nuclear reactors, you're not going to significantly reduce CO2 emissions.
The survey concluded from an environmental angle that a 'green' high speed line would have the following characteristics:
• Modest top speed, 200 – 250 kmh (125 - 155 mph)
• Non-carbon energy sources: renewables, nuclear
• High capacity, wide bodied, double deck EMUs
• Lightweight, low drag (articulated, smooth, aerodynamic)
• High passenger utilisation: serves major population centres
• Targets “1 person/car” market, in preference to groups
• Discourages travel growth (e.g. longer commuting distances)
• Provides capacity for parcels, mail and similar services
http://www.engineering.lancs.ac.uk/rese ... impact.pdf
I'm sceptical about the proposed 220mph maximum speed in California. The Spanish planned this top speed for their Madrid - Barcelona high speed line but this has now been scaled back to 186mph. Similarly, the Japanese who have decades of experience in high speed rail travel, were planning 220mph from 2011 for their 'Fastech' Shinkansens, but again this has been scaled back to 199mph (320kph). Problems with noise, pressure changes in tunnels and general wear and tear suggest that 200mph is about the limit for conventional high speed railways.