Brad Templeton: That transit is a significantly greener way to get around than private car travel almost goes without saying in our thoughts and discussions. Disturbingly, this simply isn’t true. … City diesel buses and electric trolley buses are both mildly
There are in fact massive government subsidies for construction of rail in Toko -- since 1962, about 70% of subway construction costs are covered by governments.
Since much of the ongoing cost of any large infrastructure project is the cost of capital, if you don't consider government subsidies for construction and possibly the provision of credit on relatively easy terms, you're missing a big part of the financial picture. What's the difference between a government subsidy and a loan at a rate of interest hardly above the inflation rate? You tell me. How about if you can remove capital costs from your balance sheet, report a "profit" as a result, and thus qualify for a subsidy proportional to that "profit? Well, then you use the subsidy payments to cover interest on the loan, right? Maybe even pay back some of the principal.
Don't get me wrong -- I love the train system here. I think it's the way to go. But mass transit has always required subsidies, and probably always will.
just because there are some plausible mechanisms of action for sitting on a train to encourage more trains to run does not mean that the marginal energy use of sitting on a train is the same as the average energy use of sitting on a train.
Making the train fractionally heavier is trvial. Crowding is not so important, presumably its effect could be markedly reduced by sitting in the corner. As for the future transit planners, if they enlarge transit systems, so that there are more trains, this will not only reduce crowdnedness but also reduce waiting times for trains, encouraging trains to be fuller.
It is worth at least pointing out the MUCH lower net energy consumption per capita in mass-transit heavy cities like NYC as a suspiciously relevant datum in this discussion.
Yes, I believe it wins on the deaths, especially national averages. Traffic deaths are more common on high speed roads than low speed ones, in addition.
The figures compare all transit to all cars. Most cars get better mileage on the highway than on city streets, but hybrid cars like the Prius, and electric cars, get better mileage on city streets. Transit figures include both city street transit and longer range transit, such as commuter rail which competes with highway. Commuter rail tends to be more efficient than intracity transit, because it has higher loads, makes fewer stops, and often doesn't run much at all outside of rush hour.
However, don't forget the core point. We usually work from the assumption that transit is much more efficient than private cars, and the assertion that transit is a bit more efficient than cars on city streets and less efficient than cars on the highway does not alter the conclusion that this is a poor assumption.
If you prefer to ask a more specific question, "which is greener, a Prius or a city bus" many would be surprised to learn it is the Prius, by a good margin. (Leaving out the debate on the energy cost of making both of them.)
This depends a lot on the local grid. The U.S. grid is 50% coal, 20% natural gas, 20% nuclear and 10% hydro. In some places it is much heavier on the coal, in others more hydro.
Coal is one of the dirtiest sources of power. It does CO2 but a whole lot more, and then has coal ash residue when done. Natural gas is CO2 and not too much else.
As for hydro and nukes -- well, no direct air pollution, but many people feel hydro has destroyed valleys, ecosystems and species. And people are of course mixed on how clean nuclear power is -- some think it is the riskiest and dirtiest power, others think it is the cleanest.
In terms of air pollution, coal is worst, diesel 2nd, gasoline 3rd, natural gas 4th, nuke and hydro much lower. It's an open question if an electric train that gets half its power from coal and 20% from natural gas is cleaner than a diesel bus or gasoline car. By CO2, a bit cleaner but by other pollutants, not so clear.
If you're talking about being green, you should ask about pollutants, not just about MPG. A motorcycle gets great gas mileage, yet typically pollute more than cars, because larger engines burn cleaner. Rail systems using electric power generation probably generate a lot less pollution per passenger mile.
If you intend to increase "efficiency" by getting rid of solo car drivers, wouldn't you also want to get rid of any bus routes which average under 7 passengers or so?
I welcome your cites for the figures you quote. The data I was using specified MTA motorbus figures at 1.95 million passenger miles and 5.4 billion BTUs for a BTU/pm of 2790 which is better than the average car nationwide, and I don't have a problem with the suggestion that this is twice as good as the average NYC private car, though 3 times seems a bit high.
Nobody doubts that NYC is the most transit-using city in the USA, as well as one of the most congested. And nowhere in my article do I state otherwise. I say several times the figures are national averages. Rather than just telling me I'm an amateur getting it wrong, it would be preferable if you correct we with your own cited facts -- and that you correct what I actually wrote, rather than what you imagine I wrote.
Other factors that may lead to misreading of the numbers: The figure for cars is for cars. It does not include trucks and SUV, which have their own bar on the chart. While I have not seen NYC specific numbers for cars, they might also be biased by incorrectly including cab drivers in car occupancy.
Give me solid cited facts and I will correct my articles gladly. Speak in ad hominem and you will not receive further response. Show me how an MTA bus is more efficient, on average, in New York, than a Prius, especially one with 2 people in it.
Intellectual curiosity into subjects which are not of one's own field of study is highly admirable. But amateur interpretations of data must be coupled with expert guidance.
I have seen the models used by engineers, and in New York City at least, the bus fleet has a fuel efficiency per passenger-mile which is two to three times higher than the average private car in the city. These models do indeed account for factors such as weight per axle. Doing otherwise would be foolish.
There are real people (I am lucky to know some) who study transportation engineering for years and are paid real money to make the most accurate estimates possible given our current incomplete understanding. They rely on hundreds of pages of data and research and on computer models that took years to develop, not simply on one or two tables of data covering all rural, urban, and suburban areas in one of the world's most populous nations.
Before dilettantes dismiss the work of professionals with phrases like "does not seem to be the case" and "appears to be a myth", a sense of intellectual humility and cognitive flexibility are called for.
For example, every person taken off the road with mass transit increases the mpg of the remaining persons on the road. Persons on the road experience more congestion and accidents with more persons on the road; taking persons off the road result in fewer fatalities.
When you start viewing transportation as a system, it is hard to tweek one variable and not affect another component. You might want to model SYSTEM costs and SYSTEM mpg under various mixes of public transportation and car travel.
This stands to reason. I find it very telling that nobody has bothered to respond to your message. The subway is surely similarly more efficient with the density of people who can ride it.
Is Mass Transit Green?
As a bus passenger, you should expect to observe a higher-than-average occupancy, since you're more likely to be on a more popular bus.
There are in fact massive government subsidies for construction of rail in Toko -- since 1962, about 70% of subway construction costs are covered by governments.
http://www.jrtr.net/jrtr23/...
Since much of the ongoing cost of any large infrastructure project is the cost of capital, if you don't consider government subsidies for construction and possibly the provision of credit on relatively easy terms, you're missing a big part of the financial picture. What's the difference between a government subsidy and a loan at a rate of interest hardly above the inflation rate? You tell me. How about if you can remove capital costs from your balance sheet, report a "profit" as a result, and thus qualify for a subsidy proportional to that "profit? Well, then you use the subsidy payments to cover interest on the loan, right? Maybe even pay back some of the principal.
Don't get me wrong -- I love the train system here. I think it's the way to go. But mass transit has always required subsidies, and probably always will.
If public transport runs closer to capacity, it'll be pretty damn efficient.http://awesome.good.is/tran...
just because there are some plausible mechanisms of action for sitting on a train to encourage more trains to run does not mean that the marginal energy use of sitting on a train is the same as the average energy use of sitting on a train.
Making the train fractionally heavier is trvial. Crowding is not so important, presumably its effect could be markedly reduced by sitting in the corner. As for the future transit planners, if they enlarge transit systems, so that there are more trains, this will not only reduce crowdnedness but also reduce waiting times for trains, encouraging trains to be fuller.
Yes a cost of driving cars is inducing more roads to be built.
It is worth at least pointing out the MUCH lower net energy consumption per capita in mass-transit heavy cities like NYC as a suspiciously relevant datum in this discussion.
Yes, I believe it wins on the deaths, especially national averages. Traffic deaths are more common on high speed roads than low speed ones, in addition.
The figures compare all transit to all cars. Most cars get better mileage on the highway than on city streets, but hybrid cars like the Prius, and electric cars, get better mileage on city streets. Transit figures include both city street transit and longer range transit, such as commuter rail which competes with highway. Commuter rail tends to be more efficient than intracity transit, because it has higher loads, makes fewer stops, and often doesn't run much at all outside of rush hour.
However, don't forget the core point. We usually work from the assumption that transit is much more efficient than private cars, and the assertion that transit is a bit more efficient than cars on city streets and less efficient than cars on the highway does not alter the conclusion that this is a poor assumption.
If you prefer to ask a more specific question, "which is greener, a Prius or a city bus" many would be surprised to learn it is the Prius, by a good margin. (Leaving out the debate on the energy cost of making both of them.)
This depends a lot on the local grid. The U.S. grid is 50% coal, 20% natural gas, 20% nuclear and 10% hydro. In some places it is much heavier on the coal, in others more hydro.
Coal is one of the dirtiest sources of power. It does CO2 but a whole lot more, and then has coal ash residue when done. Natural gas is CO2 and not too much else.
As for hydro and nukes -- well, no direct air pollution, but many people feel hydro has destroyed valleys, ecosystems and species. And people are of course mixed on how clean nuclear power is -- some think it is the riskiest and dirtiest power, others think it is the cleanest.
In terms of air pollution, coal is worst, diesel 2nd, gasoline 3rd, natural gas 4th, nuke and hydro much lower. It's an open question if an electric train that gets half its power from coal and 20% from natural gas is cleaner than a diesel bus or gasoline car. By CO2, a bit cleaner but by other pollutants, not so clear.
If you're talking about being green, you should ask about pollutants, not just about MPG. A motorcycle gets great gas mileage, yet typically pollute more than cars, because larger engines burn cleaner. Rail systems using electric power generation probably generate a lot less pollution per passenger mile.
magfrump,
If you intend to increase "efficiency" by getting rid of solo car drivers, wouldn't you also want to get rid of any bus routes which average under 7 passengers or so?
Perhaps everyone should just sit at home.
Seinberg,
Manhattan + the boroughs comprise only about 1/3 the population of the NY Metro Area.
NY Metro's density is 2,744/sqmi.LA Metro's density is 2,665/sqmi.
http://en.wikipedia.org/wik...http://en.wikipedia.org/wik...
I welcome your cites for the figures you quote. The data I was using specified MTA motorbus figures at 1.95 million passenger miles and 5.4 billion BTUs for a BTU/pm of 2790 which is better than the average car nationwide, and I don't have a problem with the suggestion that this is twice as good as the average NYC private car, though 3 times seems a bit high.
Nobody doubts that NYC is the most transit-using city in the USA, as well as one of the most congested. And nowhere in my article do I state otherwise. I say several times the figures are national averages. Rather than just telling me I'm an amateur getting it wrong, it would be preferable if you correct we with your own cited facts -- and that you correct what I actually wrote, rather than what you imagine I wrote.
Other factors that may lead to misreading of the numbers: The figure for cars is for cars. It does not include trucks and SUV, which have their own bar on the chart. While I have not seen NYC specific numbers for cars, they might also be biased by incorrectly including cab drivers in car occupancy.
Give me solid cited facts and I will correct my articles gladly. Speak in ad hominem and you will not receive further response. Show me how an MTA bus is more efficient, on average, in New York, than a Prius, especially one with 2 people in it.
Intellectual curiosity into subjects which are not of one's own field of study is highly admirable. But amateur interpretations of data must be coupled with expert guidance.
I have seen the models used by engineers, and in New York City at least, the bus fleet has a fuel efficiency per passenger-mile which is two to three times higher than the average private car in the city. These models do indeed account for factors such as weight per axle. Doing otherwise would be foolish.
There are real people (I am lucky to know some) who study transportation engineering for years and are paid real money to make the most accurate estimates possible given our current incomplete understanding. They rely on hundreds of pages of data and research and on computer models that took years to develop, not simply on one or two tables of data covering all rural, urban, and suburban areas in one of the world's most populous nations.
Before dilettantes dismiss the work of professionals with phrases like "does not seem to be the case" and "appears to be a myth", a sense of intellectual humility and cognitive flexibility are called for.
Seconded on the passenger-miles-per-death front.
Not a very dynamic analysis.
For example, every person taken off the road with mass transit increases the mpg of the remaining persons on the road. Persons on the road experience more congestion and accidents with more persons on the road; taking persons off the road result in fewer fatalities.
When you start viewing transportation as a system, it is hard to tweek one variable and not affect another component. You might want to model SYSTEM costs and SYSTEM mpg under various mixes of public transportation and car travel.
This stands to reason. I find it very telling that nobody has bothered to respond to your message. The subway is surely similarly more efficient with the density of people who can ride it.
It's cheaper to build out on Long Island or in New Jersey, too! But there's still less sprawl in New York.