On Oct. 26, Tesla is set to demonstrate its newest baby — long-haul trucks — but it has missed a technically easier target: commuter trains. Here on the Peninsula, politics, money and confusion have turned the iron-horse modernization discussions into horse meat.
The competing proposals are incompatible. Yes, intercity high-speed rail transit will be important in the future. But right now, we need to rethink our commuter rail system, which has been around since Abraham Lincoln was president.
To minimize the cost, improvements have been made piecemeal. We need to revitalize the entire system to encourage people to leave their cars at home — not just to go to work but to attend events in neighboring cities.
We need to facilitate commutes from south of San Jose so that housing pressure will be reduced and industry can flourish. The technology exists, right here in Silicon Valley; we just need to harness it and replace the antiquated Caltrain system.
No one imagined 30 years ago that batteries could dramatically reduce the cost of commuter rail service by eliminating both third rails between stations and the need to change many existing grade crossings. Unfortunately, this proposed commuter system is incompatible with intercity High-Speed Rail.
Electrification has begun on an old Caltrain system that is ill-suited to commuter needs and demands very expensive grade crossing updates. Caltrain wants the money for the electrification and apparently does not care that the resulting commuter train is a disaster. It is not too late to do the job right, optimizing both the commute and High-Speed Rail systems at reduced cost.
In the trenches
Burying the high-speed electric train has become a priority — but trench depth is crucial. In heavily populated areas, placing the high-speed electric train largely in a shallow trench would be practical, with the price of construction a fraction of the cost of a tunnel. Low-height BART-like cars would operate in 10-foot-deep trenches without third rails or overhead wires.
In most areas, the trenches could be covered over by buildings or parks, and the real estate reused, recouping perhaps $4 million per acre. Passing over creeks and under roads would be far more easily done with a low-height tunnel/trench. Imagine the commuter train running often beneath the existing Caltrain tracks. As those tracks would be used after midnight for freight, there would be no urgent need to change the grade crossings for safety or traffic reasons. No excavations for underpasses. Nothing removed. In open areas, the commute train could use the old tracks. In the long run, the disruption created by the old tracks might become history, as freight goes via Tesla trucks, and the unused tracks removed. Yahoo!
New design required
Commute requirements demand a different type of passenger car design from the existing Caltrain double-deckers:
• The lower the car height, the shallower the trench, the cheaper the dig.
• Bicycles could be loaded quickly through a side door — not lifted into a baggage car. Spaces could be reserved and paid for in advance for ease of access, with cell phone payment and ID. Whatever it is, it has to be fast!
• Disabled folks could also board quickly through a side door into a compartment. No time-consuming steps to lower and lift, no pallets, no delays. No long aisles. They could just roll on.
• This proposed car is nothing like the existing Caltrain cars; it is designed for commuters, period.
A battery-powered commuter train would meet the requirements of fast acceleration, elimination of a third rail and overhead wires between stations, and ready deployment of single-car trains.
Here are the nuts and bolts: With the train operating on $50,000 of Tesla-like car batteries, its acceleration and grade tolerance could be at least twice that of a diesel-electric. Third rails would be needed only in the stations.
Even better, inductive charging could eliminate the need for a third rail and ease safety concerns. Add in regenerative braking, and much of the energy used in accelerating the train could be recovered by using the motors as generators: slowing the train, recharging the batteries, recycling the energy.
Because no overhead wires or third rails would be needed between stations, work on overhead wires could stop immediately.
Trying to make a commuter rail mesh with a system designed for intercity travel is wasteful. A commuter rail requires fast acceleration and rapid adjustment to meet passenger demands. Special event and frequent evening service could be easily accommodated with shorter — or longer — trains as needed. The high-speed rail, by contrast, does not require fast acceleration or flexible scheduling. Instead, it would be more economical to run longer trains less frequently, on set schedules.
However, such a system is unfriendly to commuters — and inflexible. We have found that Caltrain's poor nighttime service makes it difficult to use public transit to attend social and cultural events.
Instead of trying to turn the high-speed rail into a one-size-fits-all form of transportation, we need to link efficient commuter and long-distance trains at transit hubs.
The best commute system for the Peninsula is clearly practical with today's technology and at far lower cost than a compromise Caltrain conversion that promises awful commuter service.
Allen Podell is an electrical engineer and inventor living in Palo Alto. He can be reached at firstname.lastname@example.org.