I was just nattering about Amtrak's plans to replace much of their fleet and thought about the 15X units. You expect about 30 years out of a DMU, 150's are about 33/34 years old, and 156/8 around 30-ish.
Any contracts signed today will result in new trains in service around 2025, so it would make logical sense to get the ball rolling now on replacing those. The large numbers means it will likely take a while to produce all the sets needed!
I can think of many reasons to replace them:
- 150's are relatively reliable, however, 158's in perticular are pretty problematic, 156's aren't perfect either! Obviously the more they age, the more likely they will need to be rebuilt/refurbed, at a cost that is likely uneconomic.
- Crashworthiness - not really an issue if/when the few seconds where it definately is! Newer units will be a lot more crashworthy, which is worth considering.
- Noise - 150's, 153's and 156's are really noisy, especially when windows are opened during warmer weather. Units like 319's have similar levels of noise insulation, but the lack of noisy diesel engines makes the experience a lot more pleasent!
- Passenger Comfort - Air Conditioning is available in even cheap second hand cars these days - something you can't say for 15X, apart from the 158 (still unreliable on those units). Noise is obviously still a factor, as well as dated interiors and a lack of some acessibility features we might come to expect in newer units.
- Pollution - Obviously new units would probably still run on diesel, but the engines would probably be a tad more efficient and much cleaner.
- Acceleration/Top Speed - Obviously likely to be better on newer units, with all of the service improvement that entails!
Unfortunately, I think like others have pointed out, there are likely to be issues in regards to electrification. Wanting to phase out diesel propulsion by 2040 is a reasonable and achiveable goal, however the government doesn't seem to be interested in addressing it. I guess this is where a strategy combining electrification and rolling stock comes into place. Indeed, electrification opens up a lot of possibilities for routes, as there is generally a fairly steady supply of solid 2nd hand EMUs, which tend to last a little longer than their DMU counterparts. The electrification of routes, especially ones feeding into electrified mainlines *cough*Windemere*cough*, also allows for newer DMUs to be cascaded onto some of the more rural lines.
Most manufacturers will admit technologies like Hydrogen and especially batteries, aren't really the most economic method of providing a good level of service on a lot of routes. They have their place, make no doubt about it, but there is no magic bullet.
So really you have two options:
1 - electrify and cascade newer DMUs to some of the rural routes that can eventually use hydrogen/battery technology.
2 - admit you probably won't do a rolling programme of electrification and build DMUs/Bi-Modes with the intention of running them past 2040.
I don't think this awkard position of limbo - where we make promises with no concrete plan on how to achieve them - is viable, esepcially for the services millions of people rely on each day.