Rail emissions

[whole diary]

[CyclingSid]

The Rail emissions 2019-20 report has been released by ORR^» (Office of Rail and Road formerly Office of Rail Regulation - about):
https://dataportal.orr.gov.uk/statistics/infrastructure-and-emissions/rail-emissions/

[Bmblbzzz]

Key results
For passenger trains, electricity usage increased by 5.3% and diesel usage increased by 1.5% compared to 2018-19. Over the same time period, passenger kilometres decreased by 1.3%.
The resulting CO2e emissions for passenger trains have fallen to 35.1g CO2e per passenger km. This is the lowest level since the comparable time series started in 2011-12.
The amount of diesel consumed by freight trains in 2019-20 has increased by 12.5% to 172 million litres. This is the highest figure since 2015-16, and the first time that diesel use increased year on year since 2015-16. Electricity usage fell by 6.3% to 70 million kWh.
The resulting CO2e emissions for freight trains have increased to 27.5g CO2e per tonne km. This is the highest level since the comparable time series started in 2011-12.

Surprising (perhaps) that it takes more energy, it would seem, to transport one passenger than a whole tonne of freight. Presumably this is due to higher speeds and more frequent stopping and starting of passenger trains compared to freight trains?

[grahame]

Surprising (perhaps) that it takes more energy, it would seem, to transport one passenger than a whole tonne of freight. Presumably this is due to higher speeds and more frequent stopping and starting of passenger trains compared to freight trains?

Statistically flawed comparison ... 1700 tonnes on a Stone train from Merehead versus 24 on the average train out of Stranraer ...  factor of 70 "units" difference.   Yes - I have chosen extreme cases; some will be in proportion to the number of units, but much will be in relation to the number of engines / number of trains.   And with wagonload freight having been pretty much wiped out apart from very specialist stuff like nuclear flasks ...

[mjones]

The CO2 figures also reflect the greater use of electricity for passenger use compared with freight, which is mostly diesel.

[stuving]

It's hard to know what to make of that "data release". It's rather sketchy, with only a few figures quoted, and I'd want to see the underlying data series, for example for passenger km. I found some, all needing to be hunted for separately, and the latest passenger km ones are for calendar years, and marked as updated 4 June 2020 and next updated 8 October 2020. Worse, the 2019-20 data are affected by the lockdown, short though the overlap was. So all the trends are pretty meaningless.

[broadgage]

Surprising (perhaps) that it takes more energy, it would seem, to transport one passenger than a whole tonne of freight. Presumably this is due to higher speeds and more frequent stopping and starting of passenger trains compared to freight trains?

Statistically flawed comparison ... 1700 tonnes on a Stone train from Merehead versus 24 on the average train out of Stranraer ...  factor of 70 "units" difference.   Yes - I have chosen extreme cases; some will be in proportion to the number of units, but much will be in relation to the number of engines / number of trains.   And with wagonload freight having been pretty much wiped out apart from very specialist stuff like nuclear flasks ...

Yes, to transport 100* tons of passengers requires about 1,000* tons of train and that is presuming reasonably full trains. Allowing for lightly loaded services such as INTO London in the evening peak, and off peak services in general, 10,000 tons of train for 100 tons of passengers might be more reasonable.

To move 100 tons of freight is unlikely to need more than 100 tons of train, empty weight, or 200 tons with the 100 ton payload. Or say 300 tons of train on average allowing for most wagons being empty one way.

Passenger trains also consume energy for heating, cooling, and lighting. Most freight has no such needs.

*Due to the many variables, no great accuracy can be claimed in this, but as approximations.
100 tons of passengers=about 1000 people including clothing and hand luggage.
To convey 1000 people needs about two full length IETs^▸ (Intercity Express Train) (seating capacity varies in different version but is about 500)
Full length IETs weigh ABOUT 500 tons with passengers. (varies a bit depending on version, and on 5+5 versus 9 car)

Figures for other types of train will vary but should be "in the same ball park"

[grahame]

The report is "all" about CO2 ... but what about other emissions?  I observed a Zoom meeting yesterday where SWR^» (South Western Railway - about) were talking about train developments and one of the things that came through was a continued progress on better trains.  Talk of the modernisation of class 442 to have anti-slip braking, of better suspension on the new(er) trains arriving on the Isle of Wight from next week, and of a cleaner air system fitted to a class 159 which reduced NO2 by 80% and particulates by 95%.   Those sound astonishingly good figures - does that mean that the engines have been pretty awful in what they have put out until now, or that they are now almost miracle-clean from a good start anyway?

[stuving]

The report is "all" about CO2 ... but what about other emissions?  I observed a Zoom meeting yesterday where SWR^» (South Western Railway - about) were talking about train developments and one of the things that came through was a continued progress on better trains.  Talk of the modernisation of class 442 to have anti-slip braking, of better suspension on the new(er) trains arriving on the Isle of Wight from next week, and of a cleaner air system fitted to a class 159 which reduced NO2 by 80% and particulates by 95%.   Those sound astonishingly good figures - does that mean that the engines have been pretty awful in what they have put out until now, or that they are now almost miracle-clean from a good start anyway?

The SWR/Porterbrook/Eminox programme for the 159s is more than a "cleaner air system" - as the graphic shows, but doesn't spell out. It's a retrofit of the same kind of SCR exhaust treatment that takes your bus engine up the NRMM stages, and going from an old engine to one meeting IV or even IIIb does involve that kind of reduction. In this case they are not promising the outcome as an NMRR level - I think that, while not still an experiment, it's still being proved.

There's words in this rail industry/RSSB^▸ (Rail Safety and Standards Board) report called Air Quality Strategic Framework, from June 2020:

In addition to DPFs, the use of selective catalytic reduction (SCR) has grown rapidly
over the last five years. SCR is used to reduce NOx emissions from diesel exhausts
by injecting a reducing agent (urea) into the exhaust. When the correct exhaust
temperatures are reached in the exhaust stream SCR can reduce NOx emissions by
over 95%.
In the UK^▸ (United Kingdom), the bus sector has recently received government funding for SCR retrofit
systems to be installed on older buses. The aim of this is to bring bus tailpipe NOx
emissions in line with the latest Euro VI standards (Barrett, 2019). To be eligible to
receive this funding, exhaust retrofit devices need to meet the requirements set out
by the Clean Vehicle Retrofit Accreditation Scheme (CVRAS).
In the rail industry, Porterbrook is collaborating with Eminox, a UK based leader in
aftertreatment technology, to deliver the Green Rail?Exhaust After Treatment System
(GR-EATS) project. This project seeks to transfer proven on-road aftertreatment
technology to a railway operating environment, with the first being installed on a
South Western Railway Class 159. The project will:
? ensure the system conforms with applicable rail standards
? ascertain ongoing maintenance requirements
? establish emissions performance and durability.

[TaplowGreen]

At what point in its lifespan will HS2^▸ (The next High Speed line(s)) be carbon neutral?

Presumably as it's all brand new kit, pretty early?

[stuving]

At what point in its lifespan will HS2^▸ (The next High Speed line(s)) be carbon neutral?

Presumably as it's all brand new kit, pretty early?

For fuel use, that must depend on the national electricity supply's carbon status. Otherwise the boundary you draw can include more or less extra stuff if you want, like building the trains or indeed feeding the staff! But why would new electric trains be very different from old ones? Faster ones use more juice, of course, which must be more relevant.

[TaplowGreen]

At what point in its lifespan will HS2^▸ (The next High Speed line(s)) be carbon neutral?

Presumably as it's all brand new kit, pretty early?

For fuel use, that must depend on the national electricity supply's carbon status. Otherwise the boundary you draw can include more or less extra stuff if you want, like building the trains or indeed feeding the staff! But why would new electric trains be very different from old ones? Faster ones use more juice, of course, which must be more relevant.

Yes this picks up on your point re: faster trains amongst others - seems like it'll never be carbon neutral.

https://iea.org.uk/hs2-wont-help-the-government-meet-its-climate-change-goals/

[stuving]

At what point in its lifespan will HS2^▸ (The next High Speed line(s)) be carbon neutral?

Presumably as it's all brand new kit, pretty early?

For fuel use, that must depend on the national electricity supply's carbon status. Otherwise the boundary you draw can include more or less extra stuff if you want, like building the trains or indeed feeding the staff! But why would new electric trains be very different from old ones? Faster ones use more juice, of course, which must be more relevant.

Yes this picks up on your point re: faster trains amongst others - seems like it'll never be carbon neutral.

https://iea.org.uk/hs2-wont-help-the-government-meet-its-climate-change-goals/

Yes ... but ... it is from the IEA, after all. The underlying point is that, once electricity is decarbonised - and that is at least doable with known technology - you can't offset anything by switching how or how much you use it. So offsetting any construction (all that cement), which is already hard to do (and arguably impossible for true carbon neutrality), becomes impossible.

[ellendune]

There are big issues out there with embedded carbon.

You can reduce the carbon footprint of a building by making it out of wood.  That can be made to keep the heat in in Winter, but it then overheats in summer. The lowest energy use of a building is therefore projected to be one that has concrete floors to give a thermal inertia.  Its no coincidence that timber buildings are only traditional in cold countries!

Of course the energy for cooling can come from solar power, but the cooling system also has its embedded carbon. And the more electricity we need the more embedded carbon is in our energy networks, so saying it doesn't matter how much electricity we use because it is renewable may not stack up. It just goes to further show that all this is not a simple as it seems. 

Net zero carbon will need us to find carbon sinks like this

[broadgage]

One must be careful to differentiate between the carbon emissions produced by USE of a railway or other infrastructure, and those produced by BUILDING the infrastructure.

The emissions produced by USE of HS2^▸ (The next High Speed line(s)) are unknown, since they will largely depend on the future carbon intensity of yet to be produced electricity. Some repairs and replacements of infrastructure will be needed, but the future carbon intensity of concrete, steel, copper, and other materials is unknown.

The missions produced by BUILDING HS2 could be estimated from amounts of different materials used in construction and the carbon intensity thereof. Figures would only be estimates.

Anti HST^▸ (High Speed Train) groups have claimed that flying or driving or driving would be greener than HS2, but they tend to cheat by including the carbon emissions from building HS2, but for air or road transport including only the fuel burnt by the vehicles.
If the carbon cost building HS2 is to be counted, then they should also include the carbon costs of building roads and airports.

[TaplowGreen]

One must be careful to differentiate between the carbon emissions produced by USE of a railway or other infrastructure, and those produced by BUILDING the infrastructure.

The emissions produced by USE of HS2^▸ (The next High Speed line(s)) are unknown, since they will largely depend on the future carbon intensity of yet to be produced electricity. Some repairs and replacements of infrastructure will be needed, but the future carbon intensity of concrete, steel, copper, and other materials is unknown.

The missions produced by BUILDING HS2 could be estimated from amounts of different materials used in construction and the carbon intensity thereof. Figures would only be estimates.

Anti HST^▸ (High Speed Train) groups have claimed that flying or driving or driving would be greener than HS2, but they tend to cheat by including the carbon emissions from building HS2, but for air or road transport including only the fuel burnt by the vehicles.
If the carbon cost building HS2 is to be counted, then they should also include the carbon costs of building roads and airports.

HS2 Ltd themselves include construction and operation in their claims re: their carbon footprint (although I understand that they have now backtracked from some of these) , and make similar claims and comparisons about the road network - are these a level playing field/comparing apples with apples?

https://www.hs2.org.uk/why/carbon/