tag:blogger.com,1999:blog-293100068373105830.post623730673235209331..comments2024-03-27T09:13:58.922-07:00Comments on The Amateur Planner: How the North South Rail Link could workArihttp://www.blogger.com/profile/06058285362842737187noreply@blogger.comBlogger10125tag:blogger.com,1999:blog-293100068373105830.post-35327159372586870472015-09-24T07:33:13.522-07:002015-09-24T07:33:13.522-07:00Just, no. We have perfectly good existing technolo...Just, no. We have perfectly good existing technology (overhead catenary) to deliver power to rail vehicles. It works very well. It's relatively cheap ($5m/mile). It doesn't degrade over time. It is proven. Why would we use something that is unproven technology from a company which doesn't yet make a profit?Arihttps://www.blogger.com/profile/06058285362842737187noreply@blogger.comtag:blogger.com,1999:blog-293100068373105830.post-16277110407958416212015-09-24T07:31:32.557-07:002015-09-24T07:31:32.557-07:00I hear VW is making some very efficient diesels th...I hear VW is making some very efficient diesels these days. Oh, wait.Arihttps://www.blogger.com/profile/06058285362842737187noreply@blogger.comtag:blogger.com,1999:blog-293100068373105830.post-58292129463668382012015-08-28T10:37:10.466-07:002015-08-28T10:37:10.466-07:00Don't forget the 100 metric tons, though.Don't forget the 100 metric tons, though.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-293100068373105830.post-23226345615825771412015-08-24T08:59:18.224-07:002015-08-24T08:59:18.224-07:00Don't forget that electric trains are also muc...Don't forget that electric trains are also much cleaner than diesel. Diesel trains emit a LOT of ground-level pollution, especially when they start up again after stopping. (Ask anyone who stands in Back Bay Station for any period of time.) Converting to electric would be a huge improvement for public health in addition to being quieter and more efficient.Charlie D.https://www.blogger.com/profile/12894581357760437121noreply@blogger.comtag:blogger.com,1999:blog-293100068373105830.post-28422812620001356002015-08-23T15:21:40.432-07:002015-08-23T15:21:40.432-07:00The 3.3 kw was in Tesla's original announcemen...The 3.3 kw was in Tesla's original announcement, but Tesla announced an increase in peak power to 7 kw at no cost increase after potential customers complained they wanted more.<br /><br />By the time you account for the actual power Tesla is delivering, and scale to PowerPack pricing of $250/kwh which I assume is basically a bulk purchase discount, you might be looking at more like $3 million or less per locomotive if we're just looking at the acceleration and not worrying about range, and don't forget that the elimination of the diesel prime mover and/or overhead power lines offsets at least some of the battery cost.Joel N. Weber IInoreply@blogger.comtag:blogger.com,1999:blog-293100068373105830.post-91725917264194560342015-08-23T14:44:51.614-07:002015-08-23T14:44:51.614-07:00Tesla has no problem achieving 0-60 in 3.5 seconds...Tesla has no problem achieving 0-60 in 3.5 seconds or less with a battery powered four door sedan that weighs significantly more than gasoline powered sports cars with similar 0-60 times, and transit generally shouldn't be accelerating anywhere near that fast.<br /><br />If a 280,000 pound railroad car is 70 times heavier than a probably roughly 4,000 pound Model S with probably a roughly 1,000 pound battery pack, and you're content to have the train take five times longer than the model S to do 0-60, the train car probably needs roughly 14,000 pounds of battery (5% of its mass) to get adequate acceleration (adequate range may require a bigger battery, however).Joel N. Weber IInoreply@blogger.comtag:blogger.com,1999:blog-293100068373105830.post-73041209636066078902015-08-23T14:36:00.155-07:002015-08-23T14:36:00.155-07:00In particular, the Tesla Powerwall has a peak outp...In particular, the Tesla Powerwall has a peak output of 3.3kW. An ACS64 has a peak power of 6.4MW and if you include HEP and such you can round it up to 6.6MW, which makes a nice even 2000 Tesla Powerwalls to make sure the locomotive can haul itself up to speed. At a cost of $7 million, that more than doubles the price of the locomotive. And that's not even mentioning the 200 metric tons that it would add to the mass... even spread throughout a train of MUs, that's not exactly a small amount of mass to be carrying around.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-293100068373105830.post-12642748086258110672015-08-23T12:07:15.923-07:002015-08-23T12:07:15.923-07:00A mode of motive power that must carry its energy ...A mode of motive power that must carry its energy source will always be inferior to a mode that can off load its energy source. Trains that draw their energy from electric wires overhead or third rail have the full might of a major power plant behind them. Batteries can never compare to such power/weight ratios.<br /><br />The trains will need very strong traction power to make the steep slopes of the link tunnels navigable in reasonable time. Let's not pretend otherwise.<br /><br />Fast acceleration out of stations is also important for making schedules work.Matthewhttps://www.blogger.com/profile/02027332620204904993noreply@blogger.comtag:blogger.com,1999:blog-293100068373105830.post-22834217780755542312015-08-23T09:37:28.922-07:002015-08-23T09:37:28.922-07:00To clarify, if you can get 15 minute or so headway...To clarify, if you can get 15 minute or so headways from an outer suburb into the NSRL, providing hourly one seat rides from the outer suburb to various far side employment centers has potential to increase the value of the system, and may suggest that Fairmount Line stations could become strong employment centers in the future, since north side, Worcester, Providence, Franklin, and Stoughton (and possible extensions beyond Stoughton) lines would be able to provide one seat rides to the Fairmount Line.<br /><br />However, the NSRL may not support 15 minute headways into the NSRL itself for every branch. But 15 minute headways from Middleborough to Quincy Center might work if the entire Middleborough to South Station route were double tracked, and then perhaps Middleborough could have hourly service to each of the South Station surface platforms, NSRL, West Station, and Track 61, with Quincy Center or JFK/UMass acting as a transfer point to a train from Kingston or Greenbush for Middleborough riders who just miss the hourly one seat ride to their preferred downtown destination.Joel N. Weber IInoreply@blogger.comtag:blogger.com,1999:blog-293100068373105830.post-6504751473031650382015-08-23T09:05:14.057-07:002015-08-23T09:05:14.057-07:00Alternatively, a single station with one end of th...Alternatively, a single station with one end of the platform under the blue / green intersection at Government Center and the other end under Hawley / Summer at Downtown Crossing might work, at the cost of losing the direct SL1 / SL2 connection.<br /><br />You should be able to buy enough Tesla Powerpack capacity for $2 billion to store more power than 80 P42 locomotives can produce in 24 hours of running full throttle, which I think demonstrates that batteries and not overhead lines are going to be the way forward if the T is open to actually buying current technology. Weight distribution may require battery EMUs instead of locomotive hauled trains, and door configuration is going to be a major factor in dwell times if everyone is going to get on and off at one or more expensive underground stations; single level cars with doors at the middle of the cars in addition to the ends may end up offering a better system cost per passenger per hour capacity than multi-level cars with narrow doors.<br /><br />Pairing lines may not be optimal. Giving south side residents a one seat ride to Porter and Sullivan and Chelsea may be useful, and giving north side residents a one seat ride to Back Bay, JFK/UMass, Quincy Center, West Station, etc may also be valuable.Joel N. Weber IInoreply@blogger.com