How efficient is a train?

[30mog]

Dear fellow train fans.

To the above question we all like to answer, 'very'. Here is my view of how to justify it, or not. The following theory is applied to passenger numbers, but could easily be converted to per ton of freight instead.

Example 1) a family car might typically be 4 metres long and fuel consumption might be 35mpg. If only the driver is travelling, it is doing 35 passenger miles per gallon (PMPG). If there are three passengers as well as the driver it is doing 140pmpg. No prizes for guessing which I consider more efficient.

Example 2) a double decker bus is usually 11 metres long and fuel consumption about 5mpg. In this case we don't count the driver as he is essential and normally there to work not travel. So, in my opinion needs 29 passengers on board to be more efficient than a car with four people. But only 8 to be more efficient than a driver only car.

However, in terms of road vehicles. I believe the length of the vehicle should also be taken into account. As it is the overall length of vehicles that eventually cause traffic jams and related inefficiency.

Car: 35 mpg, 2 travellers, 4 metres long. For which the overall rating is calculated by the sum 35 x 2 / 4. Thus, it scores 17.5 overall

Bus: 5mpg, 43 passengers, 11 metres long equals an efficiency rating of 19.54.

Moving on to our favourite mode. Well they don't clog roads up except in a few cases of them being trams. And many of them are electric so MPG or PMPG cannot be applied unless anyone knows a formula to work out an equivalent. But maybe, a single car class 153 makes 2.5mpg (guess), 80 passengers, equals 200pmpg. A car would find this hard to beat. Although at about 20 metres long. An overall efficiency rating of 10 is beatable by many road vehicles. But there are other advantages to railways. Not least they can be perhaps 240 metres long, have a thousand people on board. Just 24cm of length per passenger. As oppose to 400cm or more for a driver only car.

In conclusion. There are many ways to measure the efficiency of a transport mode. And I am of the belief fuel consumption per traveller and length of road or rail used per passenger are the best indices. And evidence given justifies what I say is the problem with our road network: Not too many cars, too many with only the driver. Thus, I argue the railways should provide more incentives to lone travellers than group travellers. And provokes one final question. Why is there no way of a lone traveller, other than a 16-25, getting access to a discount card outside of south-east England?

 

[Starmill]

I suspect the unit you'd be looking at would be something like Joules per Passenger Kilometre?

Although even then if you got that data it would be difficult to account for capacity constraints maybe? Traffic jams and the effects of overcrowding?

 

[asylumxl]

I'm probably a bit of a cynic but as far as commuter TOCs are concerned I don't think they are interested in attracting new passengers, but rather extracting maximum profit from the existing (mostly captive) market.

Joys of a privatised railway...

 

[eastwestdivide]

Surely the length thing isn't right for the train calculation, as the amount of space they take up is determined by track/signalling constraints, not the length of the actual vehicles.
For a train running at 100mph on greens, that's 3 or 4 signal sections in length, a distance more in the realms of km than m.
To determine the efficiency of one form of transport over another, surely you need to look at the overall system capacity and overall fuel consumption.

 

[chuckles1066]

I'm probably a bit of a cynic but as far as commuter TOCs are concerned I don't think they are interested in attracting new passengers, but rather extracting maximum profit from the existing (mostly captive) market.

Joys of a privatised railway...

Indeed.

you will see that I posted that as bad as the rail network in this area is, it was still cheaper than using my car to commute from Bristol to Bath.

FGW weren't interested in attracting me as a new punter and so I ended up going back to using my car.

Your observations are spot-on.

 

[yorkie]

In conclusion. There are many ways to measure the efficiency of a transport mode. And I am of the belief fuel consumption per traveller and length of road or rail used per passenger are the best indices.

Fuel efficiency is just what it says it is, and nothing more.

As for vehicle size, that's a cause of congestion, which in turn can reduce efficiency, but I do not see how the comparison of road vehicle lengths and rail vehicle lengths is valid.

Reducing vehicle length is going to be of benefit to reducing congestion. But for railways, the headways between trains are greater so the vehicle length is less of an issue (up to a point, of course, which would vary depending on local circumstances).

Why is there no way of a lone traveller, other than a 16-25, getting access to a discount card outside of south-east England?

That's a question for a separate thread, in the Fare Advice & Policy section please

 

[Cherry_Picker]

I think one of the biggest blows against the car is how often 75-80% of their passenger capacity is left unoccupied (assuming 1 person in a 4 or 5 seater car) and how much all that wasted capacity can be reduced by carpool schemes and the like.

 

[rebmcr]

I don't think it's as simple as measuring the length — it's more accurately the amount of route space that it takes up. I think some sort of metric that balances both time and vehicle length is better, which would of course take into account average speed.

 

[fsmr]

I think one of the biggest blows against the car is how often 75-80% of their passenger capacity is left unoccupied (assuming 1 person in a 4 or 5 seater car) and how much all that wasted capacity can be reduced by carpool schemes and the like.

But there is a reason for that

With the issues of parking space at home, insurance and tax not to mention depreciation very few can afford to have a 2 seater car such as a Smart to commute and then a 5 or 7 seat estate to take the kids to school or cinema etc and even then if the trip then involved said passengers, you would end up having to divert home to swap cars first. This is also why limited range electric only cars will never succeed. You always need to be able to suddenly divert from that 10 mile trip into town for the 100 mile dash to hospital the other way when a close relative is rushed in
So while the car appears to be underused for some trips it is only for that trip
Bit like loads of passenger stock sat unused in the South East outside of rush hour. You need the capacity there for certain trips

Car shares again are a utopian idea, the reason most folks don't use public transport in favour of the car is flexibility. and car sharing can negate this/ Yes you don't have to queue and sit with loads of lager drinking undesirables in the rain and have some space although choice of radio station could be interesting, and you can chose who to share with but only if you both work the same hours. What if you get a call to go home early, or equally need to work late unexpectedly If anyone has never had kids then you wont know what its like to get a panic phone call off the school saying you need to come to school now, or when they get older themselves to return home urgently as something big has just kicked off
.
TBH I don't think there will ever be a push to rail for Pax outside of the South East as there just is not the capacity to cope with most lines running full or nearly full at ridiculous high fares (compared to the cost of alternatives such as mega bus and private cars)
Freight is an entirely different matter and is where rail really comes into its own, moving heavy wagon loads of aggregates or coal (what little remains) or oil and more recently the massive uptake in Container flow etc very efficiently long distances and removing the real issue on roads, LGVs

 

[The Ham]

I don't think it's as simple as measuring the length — it's more accurately the amount of route space that it takes up. I think some sort of metric that balances both time and vehicle length is better, which would of course take into account average speed.

In (road) transport modeling there are units called PCU's (Passenger care units), which "convert" all vehicles in to their equivilant as if they were all cars.

For example a car is 1, while a motocycle is 0.5 whilst lorries and buses are 3.

This takes into account not only the length of the vehicle but how easy it is for that vehicle to move though junctions.

--- old post above --- --- new post below ---

Also when looking at public transport it should be remembered that when a bus or a train has all it's seats occupied it is still not technicly full, unlike cars and other forms of personal travel options.

 

[edwin_m]

TBH I don't think there will ever be a push to rail for Pax outside of the South East as there just is not the capacity to cope with most lines running full or nearly full at ridiculous high fares (compared to the cost of alternatives such as mega bus and private cars)

If you're saying what I think you are then I don't agree.

In the South East most routes are at maximum capacity with maximum length trains in the peak hour. Increasing passenger numbers will require heavy investment in platform lengthening for longer trains, and/or track and signalling for more frequent trains, as well as the trains themselves and the depots. Also, in the London commuter market, there is little scope for rail to gain modal share as nearly everyone who is ever going to travel by train does so already - there just isn't a big number using other modes and those that do will have a reason that makes it unlikely that they will switch. Hence growth in London commuter flows is largely driven by increases in central London employment, and projections by the likes of Network Rail are based on this assumption.

By contrast the larger centres of the Midlands and North are at something of a tipping point. Rail mode share is much lower here but in those cities with reasonable surviving suburban networks there is scope to increase capacity relatively easily by lengthening trains. This would obviously need extra trains and depots and sometimes platform lengthening but it is a lot simpler than trying to do the same in the South East. In terms of demand, road congestion and fuel costs make it increasingly difficult and costly to commute by car or bus. The North in particular is also shifting from a manufacturing-based economy (where people tend to live close to their work) to service industries which tend to be based in the major cities with increasing need to commute. For all these reasons rail travel into these cities has been increasing at a much greater rate and projections assume this will continue.

 

[chuckles1066]

I think one of the biggest blows against the car is how often 75-80% of their passenger capacity is left unoccupied (assuming 1 person in a 4 or 5 seater car) and how much all that wasted capacity can be reduced by carpool schemes and the like.

To counter that argument, I'd offer the fact that I used to squeeze onto a (what I knew as a) HST at Bath Spa and stand all the way to Bristol whilst the first class carriages were, at best, 3% occupied.

I've said here previously - reduce 1st class capacity (only business sorts on £100k a year or ordinaries on expenses use it) and put more cattle class carriages on.

 

[quarella]

Well they don't clog roads up

They do at level crossings. Do we need to factor in the negative impact on fuel consumption of road vehicles?

 

[CompactDstrxion]

I think one of the biggest blows against the car is how often 75-80% of their passenger capacity is left unoccupied (assuming 1 person in a 4 or 5 seater car) and how much all that wasted capacity can be reduced by carpool schemes and the like.

Insurers do not cover car-sharing for commuter journeys where the passengers contribute to the cost of the journey. In their policies they only cover for social journeys. It is ridiculous.

 

[Cherry_Picker]

It's crazy, isn't it? In this day and age with smartphones and location aware apps you would think more could be done to get people into car sharing schemes.

 

[Metrailway]

The OP may find this interesting. Not fuel efficiency but CO2 emissions per passenger km.

From a Defra report:

Emissions of each mode of Transport:

Car: 128g of CO2 per passenger km*
Bus: 147.5g of CO2 per passenger km
Light Rail/Tramways: 71g of CO2 per passenger km
London Underground: 73.1g of CO2 per passenger km
National Rail: 53.4g of CO2 per passenger km

* Calculated by (204g of CO2 per km)/(1.6 passengers)

 

[rmt4ever]

It's crazy, isn't it? In this day and age with smartphones and location aware apps you would think more could be done to get people into car sharing schemes.

Most people would HATE sharing a car journey with a complete stranger. It would be very awkward.

 

[edwin_m]

Most people would HATE sharing a car journey with a complete stranger. It would be very awkward.

I agree. The car is a personal space, sharing it is far more upsetting IMHO than the public space on a train. Although in the train there are more people so more likely to be someone doing something unpleasant!

There's an argument that car sharing actually makes things worse because people who are prepared to tolerate the downsides are more likely to have been using public transport beforehand and transfer to the car when they realise they can halve their costs by sharing. When Leeds (I think) opened a high occupancy vehicle lane there were reports of lone drivers stopping at bus stops to see if anyone wanted a lift.

 

[DaveNewcastle]

From a Defra report:

Emissions of each mode of Transport:

. . .

DeFRA seems to have forgotten to include the bicycle in that list.

 

[30mog]

So time for me to pop back with something!

Given my minimalist approach to motoring I drive a basic Ford Ka. Which costs about 13p a mile in fuel alone. Other research I have done tends to reveal that whatever car you drive fuels tends only to be 40-50% of total running costs. Thus, in real terms every mile probably costs me about 30p. Or put another way, a round trip to London by car costs £90 in real terms. The plus side is that its a cost for up to 4 passengers not one. But for travelling alone, I value not having to drive as probably worth 20%. So, I base the price of public transport as competing against £108 in this case. But I am mindful of the cars wasted capacity when driving alone. Ultimately, I consider a return train ticket to London good value if it's £39.20 or less [40% of £108 - £4 for connecting bus/tram journey to Chesterfield or Sheffield].

Which is about what I have managed with Advance fares lately!

As David Cameron plainly states, "there are only two places money for the railways can come from..." I am not a fan of Cameron though. And you might think what I have to say next is bonkers too? What if you could buy a lifetime railcard for £3000 that entitled you to fares capped at about the cost of the fuel for driving a car the same distance? Well, £3000 - a lot of money but cheaper than a decent second hand car. I would need a loan personally, but would only be like the last loan I took out for a car. My final guess is the railway industry would say good idea if millions of these railcards are bought?

As for the formula about MPG * Passengers / Vehicle length in metres. If some form of rule is ever implemented to discriminate against wasteful road traffic. I challenge anyone to come up with a formula that is better suited. But it is obviously inappropriate to use for rail vehicles.

 

[edwin_m]

The "lifetime railcard" is an interesting thought. Helps to tackle one of the problems with different treatment of costs - that once a car has been bought it's relatively cheap to drive it, whereas with train fares the cost all has to be paid at the time of making a journey. Some people compare the train fare with the "obvious" costs of motoring (petrol and parking) rather than including the more hidden costs such as insurance, tax disc, servicing, depreciation. Admittedly if someone needs to own a car the hidden costs change very little with how much it is used.

 

[michael769]

Insurers do not cover car-sharing for commuter journeys where the passengers contribute to the cost of the journey. In their policies they only cover for social journeys. It is ridiculous.

Not true:

Motor Conference Undertaking

The receipt of contributions as part of a car sharing arrangement for social or other similar purposes in respect of the carriage of passengers on a journey in a vehicle insured under a private car policy will not be regarded as constituting the carriage of passengers for hire or reward (or the use of the vehicle for hiring) provided that:-

(a) the vehicle is not constructed or adapted to carry more than eight passengers excluding the driver
(b) the passengers are not being carried in the course of a business of carrying passengers
(c) the total contributions received for the journey concerned do not involve an element of profit

Note: If in any doubt whether a car sharing scheme arrangement is covered by the terms of a private car policy thepolicyholders[sic] concerned should make an inquiry to their motor insurers

Motor Conference is the Standing Joint Committee of the Association of British Insurers and Lloyds Motor Underwriters' Association"

and a little more clearly....

"Giving Lifts - All ABI motor insurers have agreed that if your passengers contribute towards your running costs your insurance cover will not be affected, as long as lifts are given in a vehicle seating eight passengers or less. This agreement does not apply if you make a profit from payments received or if carrying passengers is your business."

 

[broadgage]

I feel that there are too many variables to produce exact figures, but that trains are more efficient than cars most of the time, though not allways.

Not certain if the length of road vehicles is that important, most of the road space is taken up by the gaps between vehicles, not by the actual vehicle length. Fuel use is arguably of more importance than vehicle length.

Some figures for the MPG of cars are unduly optimistic due to the assumption that they always contain at least one person going where they want.
Take the example of driving a child to school, 4 miles each way in a 36 MPG car. I would argue that the REAL MPG in that case is 18 and not 36.
If a train or bus was utilised instead, then it would probably convey fare paying passengers on the return as well.

 

[Mex]

DeFRA seems to have forgotten to include the bicycle in that list.

Except we're talking about vehicles, not toys.

 

[The Ham]

Except we're talking about vehicles, not toys.

... and do you count the CO2 from a fit 20 something who cycles 100's of miles a month and so doesn't get out of breath along their flat route to work or an unfit 50 year old who pants and wheezes up a hill both ways (i.e. lives at the top of one hill and works at the top of another)?

Anyway you would probably find that once normal at rest breathing has been taken out of the equation that the grams per km are fairly insignificant, especially as most cyclists will be cycling less than 10km per day for committing purposes (the average daily commute for all people in the UK is about 14km).

The other thing to bear in mind is that the amount of CO2 produced to build and get a cycle to the end user is a lot less than that produced to do the same for a car. Then, added to that, there is the fact that maintenance of a cycle will result in a lot lower amount of materials (and therefore CO2) than a car. All of which is not taken into account on the standard CO2 rates and so therefore will more than offsets any CO2 emissions from cyclists, which is why it is missed out.

 

[Scotty]

Most people would HATE sharing a car journey with a complete stranger. It would be very awkward.

A bit like a taxi?

 

[broadgage]

It could be argued that the net carbon dioxide emmisions of even an unfit cyclist are negligable.
The carbon dioxide in exhaled breath is only that recently absorbed by the growing of the food eaten by the cyclist, there is no net increase.

Vehicle engines are returning to the atmosphere carbon that was locked up millions of years ago and therefore producing a net increase in carbon dioxide levels.

 

[quarella]

It could be argued that the net carbon dioxide emissions of even an unfit cyclist are negligible.
The carbon dioxide in exhaled breath is only that recently absorbed by the growing of the food eaten by the cyclist, there is no net increase.

As an unfit cyclist my methane emissions have increased. Do these need to be taken into consideration?

 

[Mex]

... and do you count the CO2 from a fit 20 something who cycles 100's of miles a month and so doesn't get out of breath along their flat route to work or an unfit 50 year old who pants and wheezes up a hill both ways (i.e. lives at the top of one hill and works at the top of another)?

Anyway you would probably find that once normal at rest breathing has been taken out of the equation that the grams per km are fairly insignificant, especially as most cyclists will be cycling less than 10km per day for committing purposes (the average daily commute for all people in the UK is about 14km).

The other thing to bear in mind is that the amount of CO2 produced to build and get a cycle to the end user is a lot less than that produced to do the same for a car. Then, added to that, there is the fact that maintenance of a cycle will result in a lot lower amount of materials (and therefore CO2) than a car. All of which is not taken into account on the standard CO2 rates and so therefore will more than offsets any CO2 emissions from cyclists, which is why it is missed out.

What's your point?

 

[eastwestdivide]

Except we're talking about vehicles, not toys.

Toys? Tell that to the owners of these commuter bikes:
http://www.flickr.com/photos/steffer/7487783364/