3 ms·

I think the power requirements for the train might be the limiting factor tho. It's not quite the rocket equation but you can't just drain the whole battery pa

I think the power requirements for the train might be the limiting factor tho. It's not quite the rocket equation but you can't just drain the whole battery pack on a 3% incline and get 15-30% back on the decline. a 4000 HP train is ~ 2,000 kWatts. The average diesel-electric locomotive uses 3.5-4 kwh / mile of electricity (according to chatgpt). So to go 500 miles we're looking at 53,000lbs / 26.7 tons of _just_ battery (doubled up weight to account for non lithium). The locomotive itself can weigh 120-220 tons. A freight railcar can weigh about 100tons. For a yard locomotive where they are just moving things around this could be super useful. For hauling freight around it's a potential? You're basically losing a freight car of cargo per 500 miles. And I would really want this thing to be NOT made of lithium ion cuz if the train derailed it would be fairly destructive.[

TylerE 3y ago
25 tons in a 5,000ton ore train is a rounding error. A typical locomotive carries approximately 5,000 gallons of diesel fuel, which at 7lbs a gallon is already 17 tons, not counting the weight of the tanks. The diesel engines will be even heavier (and they're Diesel Electric, so they already have electric traction motors, and the related electrical equipment). Train's don't haul just one car, they haul dozens or even hundreds.
- _hypx 3y ago
  You need something like 500 tons of batteries, even with superior efficiency numbers taken into account, to match the energy of 5,000 gallons of fuel. It is actually significant if people did the math correctly.
  - TylerE 3y ago
    That certainly changes things somewhat, but I still think railroads would jump on it if it meant, say, 1/3rd less maintenance and half the fuel costs. The move to tier 4 emissions is/was a big deal. They’re starting to have to use DPFs and SCR.
Incipient 3y ago
Your quick calc actually seems to show how viable battery locomotives are, not how viable they aren't. 25t of batteries and you save all of the hassle and maintenance of combustion.
_hypx 3y ago
Please don't trust chatGPT for this. It is likely off by a factor of 10: http://reasonrail.blogspot.com/2015/09/a-cost-to-benefit-analysis-of-railroad.html http://reasonrail.blogspot.com/2015/09/a-cost-to-benefit-ana... It looks like 22-66 kWh/mile, depending on size of train.

TylerE 3y ago

25 tons in a 5,000ton ore train is a rounding error. A typical locomotive carries approximately 5,000 gallons of diesel fuel, which at 7lbs a gallon is already 17 tons, not counting the weight of the tanks. The diesel engines will be even heavier (and they're Diesel Electric, so they already have electric traction motors, and the related electrical equipment). Train's don't haul just one car, they haul dozens or even hundreds.

_hypx 3y ago
You need something like 500 tons of batteries, even with superior efficiency numbers taken into account, to match the energy of 5,000 gallons of fuel. It is actually significant if people did the math correctly.
- TylerE 3y ago
  That certainly changes things somewhat, but I still think railroads would jump on it if it meant, say, 1/3rd less maintenance and half the fuel costs. The move to tier 4 emissions is/was a big deal. They’re starting to have to use DPFs and SCR.

Incipient 3y ago

Your quick calc actually seems to show how viable battery locomotives are, not how viable they aren't. 25t of batteries and you save all of the hassle and maintenance of combustion.

_hypx 3y ago

Please don't trust chatGPT for this. It is likely off by a factor of 10: http://reasonrail.blogspot.com/2015/09/a-cost-to-benefit-analysis-of-railroad.html http://reasonrail.blogspot.com/2015/09/a-cost-to-benefit-ana... It looks like 22-66 kWh/mile, depending on size of train.