Quote:
Originally Posted by SFBruin
I really feel like Metra should electrify some of its higher-ridership lines. It would improve the aesthetics of the system, if nothing else.
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Wait; how would stringing a bunch of wires overhead improve the
aesthetics of the system?
As is obvious from Metra's recent rolling stock purchases, aesthetics are not much of a consideration to them.
I really don't understand the hard-on that so many people get for electrification of suburban rail.
It's not really that much greener. Diesel-electric locomotives, of course, are electric locomotives that carry their generators around with them. The inefficiency of having many small generators is not dramatically different from the transmission losses suffered in sending current many miles from a central generating station. DC transmission has enormous line losses, and onboard inverters also have substantial losses. Yes, the juice can be generated by wind or solar, but surely trains aren't the lowest-hanging fruit for carbon-neutrality. Get back to me when half of our heating and aircon is done by renewables. Or even half of the auto mileage. If particulate emissions is your worry, lots of other things—natural gas or turbine prime movers, regenerative braking—could be done for a fraction of the cost.
It simply doesn't save that much time in acceleration. UP-North takes 36 minutes to make 16 stops along 14.7 miles of track (Main St Evanston to Fort Sheridan). The much faster-accelerating Metra Electric, featuring high platforms for faster loading, takes 31 minutes to make 16 stops along 14 miles of track (87th St to Flossmoor). When you're only running one or two trains an hour, those five minutes are just not that meaningful. Even if you want the acceleration possible with big electric traction motors, it's not especially important whether you're carrying the generator around with you or leaving it miles away in Grundy County. Onboard batteries and regenerative braking—or even just a higher idle rate for the prime mover— can give you more tractive effort to the motors without the expense of stringing and maintaining miles of catenary.
It costs a bloody fortune to string and maintain all those wires. Ontario's study of electrifying the Toronto suburban network found a payback period—even with cheap government borrowing—of
a century, longer than the useful life of the asset.
Change my mind.