GO Transit

[jamincan]

So basically the reason diesel locomotives have slower acceleration is some combination of increased weight and limited on-board power supply?

[SammyOES2]

Diesel engine might have something like 35% efficiency.

An electric motor could be up to 90%.  A top-notch fuel cell will be 70%.  Electrolysis might be up to 60%.  But apply all three and you end up with 38%, almost the same as diesel -- and half the efficiency of a battery-operated electric vehicle.  Really not fabulous.  My rough efficiency estimates:
35% diesel (ICE loss only)
40% fuel cell (electrolyte loss + fuel cell loss + electric motor loss)
70% battery electric (battery loss + electric motor loss)
90% OCS electric (electric motor loss only)

I'm finding this whole discussion really interesting. Are there reputable detailed studies comparing these? It seems really complex to actually figure out the relative efficiencies.

[Canard]

So basically the reason diesel locomotives have slower acceleration is some combination of increased weight and limited on-board power supply?

Exactly!

[tomh009]

A perusal of wikipedia would seem to suggest one of the benefits of the overhead catenary system is actually an increase in power over what is feasible with diesel.  Also, there is substantially less weight not having to haul around a diesel engine and a generator, but that's obviously lost on dual mode trains.

And not having to haul around a full tank of diesel fuel.

[danbrotherston]

A perusal of wikipedia would seem to suggest one of the benefits of the overhead catenary system is actually an increase in power over what is feasible with diesel.  Also, there is substantially less weight not having to haul around a diesel engine and a generator, but that's obviously lost on dual mode trains.

And not having to haul around a full tank of diesel fuel.

That probably helps too, but I imagine not as much as not having to haul around a diesel engine.  I believe this is one reason our previous high speed train attempts were powered by gas turbine engines.

[DHLawrence]

I wonder if the 1965 blackout played a part as well - fears of your high-speed train being stranded in the middle of nowhere when the power goes out.

[kps]

Aren't diesel locomotives actually driven by electric motors too?

“just as completely electric as though their power came from a third rail or an overhead wire”

   


If that sounds like a bit of sophistry, well, at least they had actual running trains.

[DHLawrence]

And back then it probably wasn't impossible to find early pure diesel engines still in use in yards somewhere.

[danbrotherston]

And back then it probably wasn't impossible to find early pure diesel engines still in use in yards somewhere.

I don't think it's impossible now.  I'm pretty sure the UPX trains are driven by a mechanical drivetrain instead of a diesel electric one.

[trainspotter139]

One of the main downsides to a Diesel-Electric Locomotive is the Diesel Prime Mover doesn't accelerate or rev up as quickly as it would in a car or a truck, and so the power output from the generator is not as nice while it revs up as it would be in a purely electric locomotive. 

Note: the 66 GO MPI MP40-3C locomotives have an EMD 710GB 16 cylinder diesel prime mover and a Caterpillar C-27 diesel engine for the Head-End Power generator. the 1(+16 on order) GO  MPI MP54AC have 2 16-cylinder Cummins QSK60 EPA Tier 4 engines as prime movers and HEP generators.

[Canard]

I see the tweets about once a week about pedestrians getting hit and killed by GO trains, but sadly yesterday a pedestrian was hit and killed right in Kitchener, at Lancaster.

We live not far from there and I cringe every time I hear a horn blow, because the trains inside the city limits use their bells. Horn means "someone is trespassing on the tracks".

Sadly this resulted in death.

[ijmorlan]

I see the tweets about once a week about pedestrians getting hit and killed by GO trains, but sadly yesterday a pedestrian was hit and killed right in Kitchener, at Lancaster.

We live not far from there and I cringe every time I hear a horn blow, because the trains inside the city limits use their bells. Horn means "someone is trespassing on the tracks".

Sadly this resulted in death.

I hadn’t heard about that. I believe that crossing has gates as well — any word on how it happened? I mean, was the person just trying to get across before the train, or is there some explanation of the circumstances? Or did it happen near the crossing, but it’s really about somebody going for a stroll on the main line?

[Markster]

The less information about the incident, the more likely that it's a suicide.

[panamaniac]

The less information about the incident, the more likely that it's a suicide.

Yes, the police have confirmed that the death is "not suspicious", which is the usual code from officialdom.

[Canard]

My other half tells me that every single train going through the crossing is now blowing its horn.