jrissman
commented
3 years ago Mike has commented that one researcher at LBL thinks battery-powered freight trains are feasible.
The only current example I've found is this project to add one battery-powered locomotive into a set of connected locomotives that work together to pull a single freight train.
The article mentions that the battery-powered locomotive can store enough energy to maintain its full horsepower (which may or may not be enough to run the train by itself) for "30 minutes on a given charge". The reason they add a battery locomotive is because this increases the fuel efficiency of the train overall, both because the battery starts fully charged at the beginning of the run, and because it can recharge with regenerative breaking.
It might be possible to use some battery locomotives, particularly on short-haul routes where the 30-minute limit isn't crippling, to improve the fuel economy of a train that also contains fossil fuel-burning locomotives. And with future battery improvements, we might expect that 30 minutes to become 60 minutes or 90 minutes or the like.
If you view the entire train as a single vehicle, that makes the train essentially a "plug-in hybrid vehicle," which is a technology type we already have in the EPS. So we could likely model this type of train (with a battery locomotive paired with some diesel locomotives) by using the "plug-in hybrid" subscript element and applying it to rail.
I'm still not convinced of the feasibility of exclusively battery-electric freight trains, due to the energy storage needs. The overhead wires or third rail still seem more likely than batteries for a 100% electric system. But we could look into it further when we work on this issue.
For rail electrification, the EPS currently includes the cost differences in the vehicles (trains / rolling stock), but it has no estimate of the costs to electrify the rail lines. This would be the major cost of rail electrification, not the cost of the vehicles.
Electric trains aren't powered by batteries. They are powered by an electrified third rail or overhead catenary wires. To fully electrify rail, these would need to be installed along all active rail lines across the country, along with electric substations and a suitable traction power return system.
There is also the issue of maintenance and reliability. For long stretches of rail running through remote areas with harsh weather conditions, such as forested mountain terrain with heavy snowfall, it can be much easier to maintain simple, unpowered rails than to maintain the electrical systems along the rail lines. Access to the substations along the route would also be needed.
The last issue is grade separation. Grade separation might be necessary in certain areas that do not require grade separation for non-electrified rail, if necessary to protect people from encountering the electrified rails or to enable vehicles to pass without contacting the overhead wires. Grade separation in urban areas can be tremendously expensive. For example, Palo Alto has looked at grade separation for the four intersections it has with Caltrain and has estimated costs of $8.5-11 billion all together, or more than $2 billion per intersection. It might be difficult for us to make an estimate of how many grade separation projects might be required to fully electrify rail or their total cost.
While it would not be easy to represent these costs in the EPS, I think it is critical that we try, if people are likely to start seriously considering implementing non-trivial rail electrification in their policy packages. Currently, these costs are omitted, so the policy looks inexpensive. (An alternative is to disallow the use of the vehicle electrification policy lever on rail. But the vehicle electrification lever is currently enabled for ships and aircraft, which are perhaps even more unlikely, so it would be odd to disallow vehicle electrification for rail while leaving the other two enabled. So I don't think this alternative is a good solution.)