1.A.3.c Railways

Last updated on 04 Dec 2014 08:38 (cf. Authors)

Short description

In category 1.A.3.c - Railways the emissions from German railways are reported.

NFR-Code Name of Category Method AD EF Key Source for (by)
1.A.3.c Railways T1, T2 NS CS no key source

Germany's railway sector is undergoing a long-term modernisation process, aimed at making electricity the main energy source for rail transports. Use of electricity, instead of diesel fuel, to power locomotives has been continually increased, and electricity now provides 80% of all railway traction power. Railways' power stations for generation of traction current are allocated to the stationary component of the energy sector (1.A.1.a) and are not included in the further description that follows here. In energy input for trains of German Railways (Deutsche Bahn AG), diesel fuel is the only energy source that plays a significant role apart from electric power.

Method

Activity Data

The total consumptions of both diesel oil and biodiesel have been taken from the German Energy Balances (AGEB, 2012) [1] and - for comparison (especially recent years) - from sales data of the Association of the German Petroleum Industry (MWV) [2].

Data on the consumption of biodiesel in railways is provided in the German Energy Balances from 2004 onward. As the Energy Balances do not provide a solid time series regarding most recent years, AD is estimated based on the prescribed shares of biodiesel to be added to diesel oil.

Small quantities of solid fuels are used for historic rail vehicles – in the main, steam locomotives that are operated for demonstration and exhibition purposes. Analysable data on consumption and the relevant emissions are available for lignite, through 2002, and for hard coal, through 2000. Outside of the scope of such data, it is not possible to calculate emissions from consumption of solid fuels. Use of other fuels – such as vegetable oils or gas – in private narrow-gauge railway vehicles has not been included to date and may still be considered negligible.

Table 1: Sources for 1.A.3.c activity data

through 1994 AGEB - National Energy Balance, line 74: 'Schienenverkehr'
from 1995 AGEB - National Energy Balance, line 61: 'Schienenverkehr'
recent years / comparison MWV - Annual report, table: 'Sektoraler Verbrauch von Dieselkraftstoff'

Table 2: Annual fuel consumption in German railways, [TJ]

1990 1991 1992 1993 1994 1995 1996 1997 1998 1999
Diesel Oil 38,458 34,121 33,822 34,197 31,919 31,054 29,548 27,806 26,541 25,016
Lignite Briquettes NO NO NO NO NO NO 1,171 798 549 541
Raw Lignite NE NE NE NE NE 61 NE NE 11 NE
Hard Coke NE NE NE NE NE 86 57 14 NE NE
Hard Coal 576 675 540 298 234 29 29 72 54 60
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
Diesel Oil 25,410 23,530 22,041 21,611 20,372 18,142 17,101 16,730 16,389 14,336
Biodiesel NO NO NO NO 176 397 498 747 810 987
Lignite Briquettes 431 216 19 0 NE NE NE NE NE NE
Raw Lignite NE NE NE NE NE NE NE NE NE NE
Hard Coke NE NE NE NE NE NE NE NE NE NE
Hard Coal 29 NE NE NE NE NE NE NE NE NE
2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
Diesel Oil 14,626 14,730 14,117
Biodiesel 949 966 922
Lignite Briquettes NE NE NE
Raw Lignite NE NE NE
Hard Coke NE NE NE
Hard Coal NE NE NE

italic: recalculated against submission 2013

Emission factors

The EF used for emission estimations in sector 1.A.3.c - Railways are of very different quality: For NOx, NMVOC, CO, SO2, and PM annually changing tier2 values computed within the TREMOD model are used, representing the development of German railway fleet, fuel quality and mitigation technologies. On the other hand, constant tier1 EF are used for NH3, all reported POPs and heavy metals.

Table 3: EF values used for 2012 estimates

Main Pollutants Particulate Matter Heavy Metals Persistent Organis Pollutants
NEC Other PM2.5 ≤ PM10 ≤ TSP Main HM5 Other HM5 Polycyclic Aromatic Hydrocarbons PCDD/F
NH3 NMVOC NOx SO2 CO PM2.5 PM10 TSP Pb Cd Hg As Cr Cu Ni Se Zn B[a]P B[b]F, B[k]F, I[1,2,3-cd]P ∑PAH Dioxins & Furans
kg/TJ kg/TJ g/TJ mg/TJ g I-Teq
(I)EF1 0.402 593 9983 0.373 1263 203 204 204 NE 0.23 NE NE 1.16 40 1.63 0.23 23 6985 IE in ∑PAH 9306 2.096

1 due to lack of better information: similar EF are applied for fossil diesel oil and biodiesel
2 country-specific tier1 value from TREMOD [3]
3 country-specific, annual tier2 value from TREMOD [3]
4 EF(PM2.5) also applied for PM10 and TSP (assumption: > 99% of TSP from diesel oil combustion consists of PM2.5)
5 tier1 defaults from EMEP/EEA GB 2013 [5]
6 tier1 values derived from (Rentz et al., 2008) [4]

Trend discussion for Key Sources

NFR 1.A.3.c - Railways is no key source.

Recalculations

Compared to submission 2013, emission estimates had to be recalculated due to corrected 2011 activity data as well as revised or newly implemented emission factors.

Given the changes in NEB activity data for diesel oil, the annual amounts of blended biodiesel were revised accordingly within TREMOD.

Table 4: Revised consumption data 2011 from final NEB 2011, in [TJ]

Diesel oil Biodiesel
Submission 2014 12,050 790
Submission 2013 10,379 684
absolute change 1,671 106
relative change 16.10% 15.45%

In addition, due to the routine revision of the TREMOD model [3], tier2 emission factors for 2011 changed due to a revised composition of this year's haul engine fleet.

Table 5: Revised EFs 2011, in [kg/TJ]

NMVOC NOx CO PM
Submission 2014 57.3 1,001 126.5 19.38
Submission 2013 57.5 1,002 126.7 19.40
absolute change -0.2 1 -0.2 -0.02
relative change -0.24% -0.09% -0.17% -0.11%

Furthermore, similar tier1 default emission factors for heavy-metal exhaust emissions have been applied for biodiesel for the first time. Here, in former submissions, no such emissions were estimated, assuming that biofuels do not contain any heavy metals. But following information regarding the corresponding EF for road transport provided in (EMEP/EEA 2013) [6], these EF represent summatory values for (i) the fuel's and (ii) the lubricant's heavy-metal content as well as (iii) engine wear.

"…With regard to the emission of all other heavy metal species, as well as trace lead content of unleaded gasoline, the fuel metal content factors provided (µg/kg) are assumed to include fuel and lubricant content and engine wear…"

Of course, there still should be no heavy metal contained the biofuels. But since the specific shares of (i), (ii) and (iii) cannot be separated, and since the contributions of lubricant and engine wear might be dominant, the same emission factors are applied now to biodiesel and bioethanol here, resulting in increased HM emissions from biodiesel.

For information on the impacts on 1990 and 2011 emission estimates, please see the pollutant specific recalculation tables following chapter 11.1 - Recalculations.

Uncertainties

Uncertainty estimates for activity data of mobile sources derive from research project FKZ 360 16 023: "Ermittlung der Unsicherheiten der mit den Modellen TREMOD und TREMOD-MM berechneten Luftschadstoffemissionen des landgebundenen Verkehrs in Deutschland" by (ifeu & INFRAS 2009) [6]. - For detailled information, please refer to the project's final report here (German version only!)

Uncertainty estimates for emission factors for all 1.A.3.b sub-categories were compiled during the PAREST research project. Here, the final report has not yet been published.

Planned improvements

Besides the routine revision of the TREMOD model used, a broad revision of the reporting of B[a]P and PAH 1-4 emissions is planned for all off-road mobile sources in order to consolidate the applied emission factors.

FAQs

Why does the party report the consumption of solid fuels in railways as 'NE'?

The party is aware, that small quantities of solid fuels are used for historic rail vehicles – in the main, steam locomotives that are operated for demonstration and exhibition purposes. But analysable data on consumption and the relevant emissions are available for lignite, through 2002, and for hard coal, through 2000. Outside of the scope of such data, it is not possible to calculate emissions from consumption of solid fuels.

Why are similar EF applied for estimating exhaust heavy metal emissions from both fossil and biofuels?

The EF provided in (EMEP/EEA 2013) [5] represent summatory values for (i) the fuel's and (ii) the lubricant's heavy-metal content as well as (iii) engine wear. Here, there might be no heavy metal contained the biofuels. But since the specific shares of (i), (ii) and (iii) cannot be separated, and since the contributions of lubricant and engine wear might be dominant, the same emission factors are applied to biodiesel and bioethanol.


Bibliography
1. AGEB, 2013: Arbeitsgemeinschaft Energiebilanzen (Hrsg.): Energiebilanz für die Bundesrepublik Deutschland; URL: http://www.ag-energiebilanzen.de/DE/daten-und-fakten/bilanzen-1990-2011/bilanzen-1990-2011.html, (Aufruf: 21.02.2014), Köln, Berlin.
2. MWV, 2013: Mineralölwirtschaftsverband (MWV, Association of the German Petroleum Industry): MWV Jahresbericht Mineralöl-Zahlen 2012 - URL: http://www.mwv.de/upload/Publikationen/dateien/MWV_Jahresbericht_2012_2YL0kh2z76m5tPF.pdf, (Aufruf: 22.02.2014), Berlin.
3. ifeu, 2013: Knörr, W. et al., IFEU - Institut für Energie- und Umweltforschung Heidelberg gGmbH: Fortschreibung des Daten- und Rechenmodells: Energieverbrauch und Schadstoffemissionen des motorisierten Verkehrs in Deutschland 1960-2030, sowie TREMOD 5.4, im Auftrag des Umweltbundesamtes, Berlin.
4. Rentz et al., 2008: Nationaler Durchführungsplan unter dem Stockholmer Abkommen zu persistenten organischen Schadstoffen (POPs), im Auftrag des Umweltbundesamtes, FKZ 205 67 444, UBA Texte | 01/2008, January 2008 - URL: http://www.umweltbundesamt.de/en/publikationen/nationaler-durchfuehrungsplan-unter-stockholmer
5. EMEP/EEA 2013: EMEP/EEA air pollutant emission inventory guidebook – 2013
6. ifeu & INFRAS, 2009: IFEU – Institut für Energie- und Umweltforschung Heidelberg gGmbH und INFRAS Zürich: Ermittlung der Unsicherheiten der mit den Modellen TREMOD und TREMOD-MM berechneten Luftschadstoffemissionen des landgebundenen Verkehrs in Deutschland, FKZ 360 16 023, Heidelberg & Zürich.
Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License