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Caltrain's electric fleet more efficient than expected

caltrain.com

81–90 of 305 posts

Re: Caltrain's electric fleet more efficient than expected

#81
post #58

This literally doesn’t matter. The energy consumption of a train is trivial compared to displacing cars. If there was a way to trade this savings for higher speed, ridership, or frequency, it would be worth it. (If there’s not, this is a free win and yay - but it’s the wrong focus)

At least it's a win for air quality for the people that live near the tracks. You could smell and taste the old diesels, was pretty annoying.

Re: Caltrain's electric fleet more efficient than expected

#82
post #2

It's hilarious but sad to watch Americans learn things that agencies abroad already know. The other example of this I saw today was that in NYC the congestion pricing has "surprisingly" slashed the number of car crashes and injuries in Manhattan. Like, duh.

How do you get the choir to sing? You preach to the choir.

When the needle is moving in the right direction, publicize that so everyone knows about it. That public info makes it harder if someone then comes around and suggests undoing/defunding or any other type of thing that stop the needle or make the needle move in the opposite direction. Keeping the info quiet makes yanking the plug very easy

Re: Caltrain's electric fleet more efficient than expected

#83
post #46

Earlier quoted context omitted.

> It’s way quieter, the cars have nicer interiors, and it is running faster and more frequently than before. Not that electric isn't a huge step up for all the usual reasons but most of that is just because it's new and hasn't been worn out yet.

Electric does help with getting cars to run quieter and faster though. With the old diesel engines, they needed more headway because of slower cold start times so there's more frequency and can hit the speed limit faster. Electric engines have high torque and are naturally much quieter.

It's not the electric motor torque that makes the difference. Caltrain used to use traditional locomotives, you'd have a single F40PH or MP36PH at one end pulling a bunch of unpowered carriages. Those locomotives were diesel-electric though, that is the diesel is only there to act as a generator while the traction motors are electric.

The Stadler KISS units are so much faster because they're EMU's (Electric Multiple Units), that is most of the wheels in a 7-car consist are powered with their own traction motors. An F40PH makes 3000 hp (2200 kW) while a Caltrain 7-car KISS consist can put out 9400 hp (7000 kW) continuous and about 50% more than that in short duration overload mode for starting. That's the reason it accelerates so much faster.

Traditional locomotive trains are completely obsolete in any sort of commuter service with frequent stops, there's just no way for them to keep up with EMU's or even DMU's. You can't solve it by just putting bigger engines on the locomotives, you wouldn't have enough weight on the wheels to make sufficient tractive effort.

Re: Caltrain's electric fleet more efficient than expected

#84
post #43
post #4

Earlier quoted context omitted.

I feel this is positive news moving in a positive direction. Do you suggest not doing anything to improve the situation? We can’t go back in time. But we can help ourselves in the future.

One way to help yourselves in the future would be to learn the meta-lesson that actually things that work in other countries mostly work the same way in the US too.

Some people take your word for it, but some people just have to touch the stove to learn that it is hot.

Re: Caltrain's electric fleet more efficient than expected

#85
post #58

This literally doesn’t matter. The energy consumption of a train is trivial compared to displacing cars. If there was a way to trade this savings for higher speed, ridership, or frequency, it would be worth it. (If there’s not, this is a free win and yay - but it’s the wrong focus)

Both speed and frequency are significantly up, and I’ve heard ridership is as well. Also, noise and pollution are substantially down. A huge win all around.

Re: Caltrain's electric fleet more efficient than expected

#86
post #60

Train technology is so behind compared to road electric vehicles. Companies that build train batteries have been trying to sell to us (car OEMs) lately, and we look at the battery specs and battery management system capabilities and go uhhhh… On the motor and control fronts as well.

Why? Just build more trains any train infrastructure is so much better than cars, they barely need improvement, they just need to be built

But for example if they used PMM squirrel cage motors etc, they would be nice and smooth, cheaper to build, more energy efficient.

On the battery front, using car-style or truck-style EV battery modules would be more robust and would reduce cost by somewhere in the order of 50%.

Instead, most trains still use induction motors (this is the high pitch whine you hear) and many train battery designs use industrial style rack mount batteries, with screw terminals, controlled by a massive PLC cabinet. In eMobility the controls are handled by a small safety-rated microcontroller.

Re: Caltrain's electric fleet more efficient than expected

#87

Earlier quoted context omitted.

If it's not magic why isn't it being done? That's the point. This news is rather pathetic strictly because a better scenario is NOT magic.

Simple. Most people don’t want it.

They do. You're not being realistic. Almost everyone would like to have a choice between getting on a subway for super cheap or driving through traffic. You're saying they would rather have no choice between the two options? Come on.

The Bay area (people) want top of the line transit, all of California wants it. It's similar to how Ethiopia wants to get out of poverty. Both places can't get what they want for similar reasons: incapability.

Take a look at the high speed rail. Probably won't finish in both of our lifetimes. People want that thing, what's stopping it from happening is incompetence.

Re: Caltrain's electric fleet more efficient than expected

#88
post #70
post #46

Earlier quoted context omitted.

Electric does help with getting cars to run quieter and faster though. With the old diesel engines, they needed more headway because of slower cold start times so there's more frequency and can hit the speed limit faster. Electric engines have high torque and are naturally much quieter.

Yup not to mention that the fumes from diesel engines got into the cars so you tended to avoid the ones close to the engine. Its a HUGE qol improvement!

Also makes waiting at either end, San Jose or San Francisco more pleasant with cleaner air to breathe instead of fumes if you are a little early.

Re: Caltrain's electric fleet more efficient than expected

#89

Earlier quoted context omitted.

Why so negative? Given that the served population is conservatively a quarter of either of those areas, doesn't seem like a fair comparison. More to the point, I've been favorably impressed with the transit options since moving here, and in terms of reliability it's been better than NYC, though obviously there are fewer trains/branches. I'd love to see BART open later, like NYC, but even Tokyo trains stop at midnight…

It's fair. NYC is 8.8 million, bay area is 7 million. Tokyo is about double that. Not being negative. Being realistic. It's unfortunate that being realistic often is negative. Transit here is garbage. You either luck out and live and work near transit or you're like most people and have to drive. A couple million in energy savings doesn't mean anything compared to the amount wasted by cars.

Surely the relevant metric is population density?

Re: Caltrain's electric fleet more efficient than expected

#90

> With the agency expecting approximately $6 million annually in energy credits from the California Air Resources Board’s Low Carbon Fuel Standard Program the first year of electric service will have lower fuel costs than the previous diesel service Thats the key. Without the subsidy its more expensive and less efficient than carbon based fuel. In the long run we are worse off, because the subsidy can't last forever.

They've significantly increased the timetable frequency though, so they're running more trains, and those trains are accelerating and running much faster than the old diesel-electrics. I don't think you're comparing like for like.
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