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A comment on California bullet train cost surges by $2.8B. Parent comment

Re:California bullet train cost surges by $2.8B by ebikelaw on Wednesday January 17, 2018 @06:13PM (#16172983)
What you’re leaving out is CO2. California is committed to reducing CO2, but emissions from transportation are the largest component of state emissions, and they are growing. Air travel cannot be done except by burning hydrocarbon fuels. Train travel, while still energy-intensive at high speeds, can be powered by any electric source. Therefore rail, and not air, has the capability to cut the state’s CO2 emissions.
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Re:California bullet train cost surges by $2.8B by bluthru on Wednesday January 17, 2018 @11:38PM (#16174744)
As a rule of thumb high speed rail is 1/10 the CO2 of flying. However, I wonder what the carbon footprint of creating the tracks is?
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Re:California bullet train cost surges by $2.8B by dx034 on Thursday January 18, 2018 @03:13AM (#16175503)
The track can be used for 1-2 centuries (as they have been in Europe). That includes many refurbishments and replacement of steel but much of the construction cost will be low per passenger.
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Re:California bullet train cost surges by $2.8B by baud147258 on Thursday January 18, 2018 @05:39AM (#16176069)
Older tracks can't be used for high speed trains. In France, all the new high-speed lines are constructed for this usage (lot of straight lines). On older lines, an high-speed train will be at the same speed as a normal commuter train.
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Re:California bullet train cost surges by $2.8B by ebikelaw on Thursday January 18, 2018 @04:46PM (#16181800)
He didn’t say they could. But tracks built today can be used forever, because wheel-on-rail technology has a hard limit at Mach 0.5 and we’ll never have faster trains than we have today.
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Re:California bullet train cost surges by $2.8B by sjg007 on Wednesday January 17, 2018 @06:36PM (#16173123)
They are working on electric powered jets kind of like the Chevy Volt. That may reduce the CO2 burden.
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Re:California bullet train cost surges by $2.8B by 0xffff2 on Wednesday January 17, 2018 @09:03PM (#16174025)
They who? I work in aerospace and while I have heard many proposals (most 20-40 years from commercial production) for improving efficiency, including hybrid electric systems, I have never once seen anyone propose an electric commercial passenger aircraft.
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Re:California bullet train cost surges by $2.8B by pretendscholar on Wednesday January 17, 2018 @08:21PM (#16173809)
This is one of my biggest gripes about the tech community. We can't wait for tech that may or may not come to fruition when we have working solutions now. Don't let great be the enemy of the good.
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Re:California bullet train cost surges by $2.8B by redorb on Wednesday January 17, 2018 @06:45PM (#16173189)
until battery power/weight ratio gets 10x better electric flying vehicles (specifically passenger jets) are dead in the water.

I don't know that we're making the right trade from atmospheric pollution co2 vs the pollution of throwing away batteries.

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