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What to do in high speed rail?

Last week, new studies came back on the California High Speed Rail project. They have raised the estimated cost to $99 billion, and dropped the ridership estimate to 36.8 million and $5.5 billion in annual revenue. Note that only around 20 million people currently fly the SF to LA corridor — they expect to not just capture most of those but large numbers of central valley trips.

Even at the earlier estimates the project was an obvious mistake, and there’s no way to financially justify spending $99 billion to pull in $5.3 billion/year even subbing zero in for the large operating cost. But for various political reasons involving getting federal money, some are still pushing for this project, and we may well build a short train to nowhere in the central valley just to get the federal bucks.

They’re planning there because the various cities in the populated areas have been fighting legal battles to block the train there, not wanting its disruption. Because the train can only stop if a very few places at the speed it wants to go, a lot of towns would end up having construction and noise and street blockage and not get a lot of use from the train.

The local opposition is a tough barrier, because the train ends up really only being useful where the people are. While I have doubts about how many people would ride the long haul, since few want to go from downtown SF to downtown LA, lots of people would ride a fast train in the urban areas. In particular, what nobody talks about is running the HSR primarily to the airport, and streamlining both security clearance and the connection with new technology. The only reason HSR is pushed as possibly competing with flights is because of the nightmare we have made of flying, where people have to get to airports 45 minutes ahead of even short-haul flights and take a fair bit of time to get out of airports on the other end and make it through traffic to their destinations. A fast train from a downtown to the airport where you clear security (and check bags) right on the train, and the train drops you right at the central gate areas post security would create an unbeatable trip from downtown anywhere to downtown anywhere.

For fast trains, the San Francisco to San Jose route is so short that a 250mph HSR could do the 48 mile trip between the towns in 12 minutes without stopping, call it 15 with the start and stop at each end. This opens up an interesting cost saving — you could build a single track, and have a train zip back and forth on it, and still provide service every 30 minutes. You could put a double-track section in the middle and have service every 15 minutes, with lots of safety interlocks of course. A single track requires less land, less of everything and could probably be built along easier routes, even highway medians in some cases. You could avoid turnaround time by having double track at the endpoints, so one train is leaving for opposite route the moment the other train arrives, giving each train quite a long turnaround — with double rolling stock.

Of course, having no stops is not that valuable because only a few people want to go from SJ to SF. People would want a stop at the airport as I have indicated, and at least one in Mountain View or Palo Alto. Each stop costs a bunch of time, and eventually the trip gets long enough that the single-track trick becomes less useful. For a while I’ve wondered if you could make trains that could dock, so that the main train runs non-stop and is able to shed cars which stop at local stops (not that hard) and to dock with cars coming from local stops (harder.) I proposed this 7 years ago near the start of this blog, and there are serious rail designers thinking along the same lines — see the video in that link.

In the Priestman Goode proposal, they have trains docking side to side. That seems much more challenging though it offers fast transfer. If you combine the two ideas, you would have two tracks — one for the nonstop trains and one for the docking shuttles which serve all the local stops. Indeed, if you could do this you could get rid of the old regular speed rail service running on existing track pairs because this would be superior in all ways except cost. My own proposals attempted to dock on a single track, which seems easier to me.

Robocars play a role in all this too. Even the HSR authority realizes they have a big problem, in that once people get quickly to an HSR station, they still have to get to their real destination. Using local transit may mean spending more time on a local bus than on the HSR. The mobility on demand of robocars is a great answer, and I’m pretty sure that with a 2030 forecast completion date (if they’re lucky) we’ll have robocars long before then. And the one thing cars can’t readily do is go very fast efficiently between cities.

The docking approach, should it work, has another advantage. The main train can take the best route (cheapest or shortest) without too much regard for where the stations are. People like stations in urban centers, but bringing the high speed train right through such areas (like Palo Alto) is hard and has caused the lawsuits. If the train goes through the industrial space along the Bay, and a spur goes into downtown for the shuttle that docks with it, you get a win all around.

Another approach that doesn’t require dock/undock works when you have a solid terminus like SF. You have 3 trains leave SF at the same time. The first one goes express to San Jose. The second goes express to Palo Alto and Mountain View and then switches to low speed tracks to go to Sunnyvale and Santa Clara. The third goes to SFO airport. Because SFO airport is also an origination point, it sends a train to SJ just before or after the one from SF, and another train to Mountain View right after that one. Mountain View to SJ service might be able to fit in or have to be local service. These sub-trains are just a few cars. This is not as energy efficient, though it can be if the trains are able to get close to one another and draft, sort of a virtual coupling without physical contact. You need perfect sync, and special long-spring collision bumpers in case the sync fails and they bump. The risk of higher-speed bumping must be prevented by failsafes that don’t even let the trains get on the same track until speed is matched close enough. This requires more than just a single track of course.