[Geezer]

I don't really care about how important realities are dealt with. What I do care about is resource depletion and environmental degradation. I am especially concerned that nobody wishes to put a cost on using the rapidly diminishing commons. We are approaching another tragedy of the commons and problems with automobile emissions and fuel usage are a sizable component. (Geezer, my taxes are really quite reasonable).

I agree Steve (except for the tax bit  []) What we really need to do is re-engineer the whole process. A very significant amount of fossil fuel is being spent by people simply going to and from their places of work. We might say that can be solved by the use if public transport, but, actually that's not necessarily true. For example, the real energy costs associated with rail transport are actually a lot higher than some people think (I'll probably need to dig up some data to justify that statement!)

I think figuring out methods to eliminate a lot of commuting entirely ought to be a high priority. That's just one example of course. Now I'll probably get beaten up by Peppercorn for derailing his thread again  [] 

[peppercorn (OP)]

Lol! - 'derailing', what are you like?!
I would like to see these figures on Rail, but even if they are high right-now I can't think of any good reason why that has to be the case - if it's down to running lots of trains too empty then it;s time to do something about that.

I'm always amazed by how many vehicles are whizzing around during the middle of the day, and not just delivery vans, etc.  In short it;s not just work traffic (although this cases the majority of jams [or is it the school run?!]) - people don;t think twice about using the motor vehicle, but I agree that changing peoples behaviour is not just about levying ever higher taxes.

[Geezer]

I'll see what I can did up on the rail thing. I seem to remember it's not just the underutilization of capital equipment, but the actual energy consumed per person mile is really quite high. I was quite surprised when I read it myself. Unfortunately, I've no idea where I saw it now.

It's an interesting example of how it's always a good idea to challenge the conventional wisdom. (You may have noted a certain tendency to do that on my part.)

[CliffordK]

Wikipedia had a good article on the costs of public transportation vs cars.  Obviously one of the big issues it the typical 1.5 people per car.

http://en.wikipedia.org/wiki/Fuel_efficiency_in_transportation

I think it is heavily US modeled, but down at the bottom there are also some UK links.

http://en.wikipedia.org/wiki/Fuel_efficiency_in_transportation#UK_Public_transport

The problem is that for public transportation to be practical, there has to be access.  I.E.  A bus should go within 1/4 or 1/2 mile of every place in the city, and should do it from about 5AM to 2AM.  Doing so, one ends up with a lot of buses circling the city empty. 

The public transportation companies don't seem to like to have a mix of, say typical 15 passenger vans, plus large buses.  Run the small vans on off-peak hours, and the big buses during rush hour.

Same thing for commuter trains.  They are worthless if you don't have access.  So the average ridership is low.  Although, this would vary a lot from community to community.  In many parts of the world, there aren't other "alternatives", and they also make schedules to try to keep the trains full.

One efficient "commuter" train system that I've been on was the Seattle Tacoma "Sounder"

http://www.soundtransit.org/x71.xml

What is unique about it is that it only has northbound trains in the morning and southbound trains in the evening (it looks like there are a couple more options now for reverse commuting).  When I was on it, the train was packed for most of the trip.  And it appears as if they've added several more trains in the last couple of years. 

I assume they have "train barns" at either end so with the exception of the reverse commutes, most of the trains run one way twice a day, with perhaps one or two trains running 3 ways.

Sorry, I don't have actual ridership and efficiency figures for the Seattle Sounder system.  It just seemed packed when I was on one of the trains a couple of years ago, and it appears as if the system has expanded since then.

[Geezer]

Thanks Clifford.

The one that's very significant is the "efficient hybrid" from the US Passenger Transportation in the Wiki page. If these figures are to believed, it's almost twice as energy efficient as commuter rail links in the US.

I do have a personal bias in favor of all forms of rail transport, but I suspect these figures don't even take into account the depressingly low capital utilization of commuter trains and rail infrastructure. Apart from rush hours, most of the stuff is grossly underutilized.

[CliffordK]

Apart from rush hours, most of the stuff is grossly underutilized.

Which is why the Seattle-Tacoma trains only run during rush hour, and primarily in one direction.

And, in our "fast-food world", public transportation can often add significant amounts of time to one's commute.

To ride the train from Eugene to Portland...  I have a 10 mile bicycle ride to the Eugene train station (other means of local commuting are inconvenient).  It then takes 3 hrs on the train rather than 2 hrs of driving.  And, once in Portland, I'm about 5 miles from my destination.  And since there is no secure place to park a car or bicycle...  I end up spending an extra $5 to take the bicycle on the train with me.  The 2 hr drive to Portland suddenly becomes a half-day trip if planned well (the last time I ended up sitting in the train station for an extra 2 hrs).

Personally, I find flying so miserable that I would rather drive 8-12 hours than to fly.  Bullet trains might help slightly. 
I hate the ideas:

Everyone pays different prices for the same flight.
You essentially get punished if you don't plan 1 to 3 months in advance.
Exorbitant prices charged for parking.
Airport access is inconvenient at best.
One is often stuck with a rental car at the other end.
In the past, I calculated that it was virtually identical in time to fly 250 miles between St. Louis and Kansas City as it was to drive between the two.

[Geezer]

Apart from rush hours, most of the stuff is grossly underutilized.

Which is why the Seattle-Tacoma trains only run during rush hour, and primarily in one direction.

Er, I think it's the other way around. The Seattle-Tacoma trains and the railway infrastructure are a grossly underutilized capital asset because they only run during rush hour. It's the same problem that all commuter railway systems suffer from. If commuters had much more flexible working hours, it might help to reduce the scale of the problem.

[Bored chemist]

"The problem is that for public transportation to be practical, there has to be access.  I.E.  A bus should go within 1/4 or 1/2 mile of every place in the city, and should do it from about 5AM to 2AM.  "
No it doesn't.
Public transport IS practical. Just about everywhere has it. Practically none run that sort of schedule.

[CliffordK]

"The problem is that for public transportation to be practical, there has to be access.  I.E.  A bus should go within 1/4 or 1/2 mile of every place in the city, and should do it from about 5AM to 2AM.  "
No it doesn't.
Public transport IS practical. Just about everywhere has it. Practically none run that sort of schedule.

It depends on the place...
Fortunately I'm pretty close to a bus line.  The nearest bus to my house (in Eugene, OR) is 4 miles one direction, and 5 miles the other direction.  First "inbound" bus leaves at 7:10 AM with 4 buses a day.  The last outbound bus leaves town at about 6:00 PM.  So much for "late nights".

In Portland, Oregon.
The first Red Trimet Max Line leaves downtown at 4:02 AM.
The last Red Trimet train leaves towards downtown at 11:49 PM, and reaches the end of the run at 12:50.
The first connecting bus heading downtown that I could ride leaves around 5:00 AM, and arrives downtown at 5:30.
And the last connecting bus leaves downtown at 12:01 AM.

Since my primary use of public transit in Portland is to connect with planes & trains, it is always a pain to make sure I can catch the public transit connections.

In NYC, the trains run almost around the clock, but that is more like a different planet.

[peppercorn (OP)]

Darn it  []  If you guys want to talk about trains all day, start a new thread!

 []

[CliffordK]

Sorry.

I think we concluded that there was more hype than reality with the efficiency of public transportation. 

Where were we?

I think the EPA testing often reports in PPM. 
However, it also appears as if the standards are actually in either gm/HP-hr
or if they are expressed in gm/mile, they also include vehicle classifications.

So, in a sense, all vehicles should be treated equally.

However, it may depend on the actual implementation of the standards.

If the question is why there are different vehicles in Europe and the USA...  I doubt it is due to the emission standards.  They seem to be close enough that there must be a different explanation.  My guess is that it has to do with the extreme redundancy in the testing and approval process.  And, while one might think a company would just have to bring new vehicles to the USA, they also have to setup a support network which means a significant investment.

[peppercorn (OP)]

I've heard that California has had particularly strict emissions standards (for smog reduction) for a number of years, but I don;t know whether they are (now) any stricter than other States, or in fact Europe.  They may have over-pushed the pollutant standards (particularly NOx) to the (further) detriment of mechanical efficiency.

[Geezer]

I've heard that California has had particularly strict emissions standards (for smog reduction) for a number of years, but I don;t know whether they are (now) any stricter than other States, or in fact Europe.  They may have over-pushed the pollutant standards (particularly NOx) to the (further) detriment of mechanical efficiency.

California pretty much set the pace that everyone else followed. Yes - they were so concerned about smog that they made catalytic converters essential, and they have to be fed a certain amount of fuel to keep them working at the stoichiometric point, so the combined thermal efficiency of the system drops. Initially I think this made quite a difference to fuel consumption, but I suspect that's no longer the case.

Concerning railways, let me just say ... OUCH!  [B)]

No need to shove!! I'll have you know I've been thrown out of far better threads than this!

[peppercorn (OP)]

Concerning railways, let me just say ... OUCH!  [B)]

No need to shove!! I'll have you know I've been thrown out of far better threads than this!

Lol! [] I must be getting a Napoleon complex!
In reality, I like a good discussion on the Joy of Tracks as much as the next geek! []


Good info on California - I often see that State's name appear on quite alot of articles summarising of pollution control history.  Now I know why []   Do you honestly think that the days of paying Peter (efficiency) to rob Paul (air-quality) are past (what with modern ECU, valve-timing, etc)?

[CliffordK]

Some of the early smog controls were a little counterintuitive, such as adding an air pump (powered by the engine) to pump fresh air into the exhaust manifold.
It probably served a minor purpose of oxidizing some exhaust gases.

In general, emissions control is about burning no more, and no less fuel than you need.  It is a good idea, and should have no significant negative impact on the fuel efficiency. 

The bigger complaint is that one doesn't necessarily get maximum power output with a "detuned" engine.

The DPF burnoff is different because it specifically sends unburnt fuel into the exhaust system.  I don't remember the exact numbers, but the calculations I saw about fuel wasting seemed significant. 

[Geezer]

Clifford, what's the DPF burnoff?

There must be quite a bit of energy wasted by the cat. They get really hot! We need to get BC to explain how this stoichiometric thing really works. All I know is that the O2 sensors are critical for maintaining it.

Peppercorn, I'm not confident about my view of the "state-of-the-art", but I don't hear people complaining about the power lost to emission controls the way they did twenty or so years ago. Also, the power per displacement values have gone up considerably, and they are probably exceeding the values that were typical prior to the institution of emission controls.

[Bored chemist]

Anyway, back at the topic.
Given the engine capacity, the RPM and the air temp and pressure you can convert from ppm to g/km anyway so who cares which one they quote?

[Geezer]

Anyway, back at the topic.
Given the engine capacity, the RPM and the air temp and pressure you can convert from ppm to g/km anyway so who cares which one they quote?

I don't think that was the question BC. By "driving cycle", I think the OP meant something other than constant power output.

[Bored chemist]

So?
You can still do the calculation. In both cases you would need to sum the result over the course of the driving cycle.
A peak just measures "how bad is this engine at its worst?" which isn't a bad thing to know.

[Geezer]

So?
You can still do the calculation. In both cases you would need to sum the result over the course of the driving cycle.
A peak just measures "how bad is this engine at its worst?" which isn't a bad thing to know.

That is true, but I'm not sure it's what the OP wanted to know.