OK, so he says it's much cheaper than high-speed rail mostly because pylons require taking much less land through eminent ___domain. Can anyone explain to me then why high speed rail can't be built on pylons?
Train cars must be connected to each other because of how trains work, whereas the Hyperloop pods are separate from each other. I haven't yet seen anyone actually crunch the numbers on the proposed weights for the Hyperloop (which are in the PDF) vs existing light rail solutions. You certainly can put a light rail up on pylons, it just might be a lot easier/cheaper to do so with the Hyperloop. I do think he's playing up the benefits of using pylons too much, since the real benefit here is the 35 minute travel time and affordable ticket cost.
Probably regulations. They have to maintain integrity in collisions. I don't know if they have to take into account having very heavy freight trains on the same tracks as well.
Train regulations are retarded in the US and haven't been reformed for over 50 years. Basically if you plan on having a crossing or sharing track with a freight train you automatically are stuck with the FRA regulations which apply to freight trains and are also pointless. Those regulations require absurd rigidity of rolling stock to the point that train-sets built for those specifications actually are more expensive to maintain, fail more often simply (rolling stock becomes too heavy), and are much more unsafe.
For example FRA requires train rolling stock to withstand 800,000lbs of force on impact without permanent damage. The European requirement on the other hand is less than half of that. The European requirements instead aim for adding "crumple zones" to the cars to absorb energy and protect occupants similar to how automobiles use crumple zones.
This is why there's an obsession in the USA regarding light-rail. Light-rail sidesteps the FRA regulations by creating a separate track and rolling stock that doesn't have crossing with heavy rail.
I believe if we simply reformed FRA regulations we could probably cut all rail development by a sizable chunk as we would be able to buy rolling stock as-is from European and Asian suppliers.
But anyway, back to the point being discussed. A sizable chunk of China's HSR network was built elevated so it is certainly feasible to put today's HSR tech on pylons. But just because you elevate something doesn't magically get you away from Environmental Reviews which I think is another area where a majority of the cost in public works project lies.
Environmental reviews will still be required for Hyperloop. Since it is actually a new system, I would expect it to get even more scrutiny in the public eye because it will sound even more magical and also offend even more people since there won't be any intermediate stops. Remember that much of the California HSR political issues are because central valley cities and towns want an HSR station in their town (of course they don't want to fund the station). So many of these towns basically come to the table and say "we'll give you the land if you give us a station, otherwise we won't help you." The Hyperloop concept basically ignores this argument.
Keep in mind that despite environmental reviews having the word "environment" in them, they are actually also public hearings where the public can voice their opinions which can include things like additional noise and traffic. For example if your project blocks out the beach view of a home-owner's house overlooking the ocean, you can sure bet that they'll be at the environmental review and give you an earful about how you can't build your tube/track/freeway/skyscraper/windmill there. Yes that's a bit of hyperbole but that's basically how the environmental review phase is abused.
Because of that, I've come to the conclusion that we won't have any significant improvement in infrastructure in this country until CEQA/NEPA are reformed to allow not just public entities to build infrastructure, but also private entities as well.
