THE GREEN TAX, AN ANALYSIS OF ITS IMPLEMENTATION IN
SPANISH SHORT SEA TRAFFICS.
Authors: Dr. F.Xavier Martínez de Osés & Marcel·la Castells Sanabra
Nautical Engineering and Sciences Department – TRANSMAR Research Group
Universitat Politècnica de Catalunya – UPC
Pla de Palau, 18
08003 - BARCELONA
ABSTRACT
The European transport policy aims to achieve a sustainable communication system. A
reduction in pollutant emissions, accident rate and traffic congestion is central to reaching this
goal. These factors are encouraging the public and private stakeholders to use more extensively
the freight rail mode and of course the maritime alternative, in a constant search for the best
solution. Most of the developed countries use a national net of roads to move freight, despite it
being the most expensive, pollutant transport mode, maintaining the highest rate of fuel
consumption per cargo unit.
The maritime sector is one of the less pollutant ways in addition to the capacity of contributing
to reduce the road congestion in Europe. Particularly, the short sea shipping is thought to be the
quickest way to reach the sustainability goal. However, this opportunity could pose some other
inconveniences such as a superior traffic growth and a subsequent increase of the pollutant
emissions in the port areas. One of the cost advantages of ships over trucks and trains is lower
fuel consumption, which depends on the relatively low speed.
On the other hand, the massive use of every day fastest ships allows them to compete with the
truck, removing the ecological ticket from the marine sector to other means, due to its greater
needs in terms of power and consumption, and thus emissions. This question is going to be
analysed in this paper for further evaluate the possibility of an ecological bonus for the trucks
using the maritime transport.
KEYWORDS
1. Short Sea Shipping 2. External costs 3. Ecological bonus
INTRODUCTION
The European transport policy aims to achieve a sustainable communication system. A
reduction in pollutant emissions, accident rate and traffic congestion is central to
reaching this goal.
In many countries a shift from congested highways to other alternatives for freight
transport has been observed. Apart from railway transport, the maritime option is often
preferred to relieve road traffic congestion and its negative environmental effects.
After Spain joined the European Union at the end of 1985, the traffic volume increase
had grown from 2.8% to 8.4% per year, accounting for a movement of 70 million
tonnes in both directions. This means a daily average of 3,500 trucks travelling through
La Jonquera and Irún passes. At this rate, by the year 2020, freight transport could
increase to a total of 250 million tonnes, with over 30,000 trucks crossing the Pyrenees.i
In view of this and the consequences of traffic congestion, a change from traditional
unimodal to multimodal transport chains involving the sea and road modes is desirable.
Freight transport is currently shared by both chains, with a slight advantage of road
over maritime transport, particularly in short distances like trips between France and
Spain while the sea option logically becomes more common as distances increase.
According to the review of the EU White Paper on Transport Policy, a 59% increase in
tonnes carried by Short Sea Shipping is expected between 2000 and 2020.
The main benefit of Short Sea Shipping lies in the possibility of combining the inherent
advantages provided by the involved modes, thus reducing costs and increasing freight
transport capacity over long distances. However, for multimodal transport to become a
real alternative to the road-only mode, the feasibility of routes must be explored with
several variables related to freight transport. Moreover, friction costs derived from the
mode shift must be quantified and reduced.
Conventional ships are typically regarded as the most viable solution since they can
penetrate the road market, sometimes leading to a decline in internal and especially
external costs. While this opinion is based on the fact that sea transport should compete
price-wise with other modes, it must be born in mind that high-speed vessels offer
greater speeds, which may be perceived as quality of service by some shippers. In some
routes, high-speed vessels can become serious competitors to road transport although
these ships pose operational problems in bad weather.
Through the Strategy for Sustainable Development of the EU White Paper on Transport
Policy,ii the European Union has expressed concern about transport-related impacts. For
this reason, appropriate policies to balance transport growth and its environmental
effects are being made.
In general, road transport accounts for over 80% of CO2 emissions. It is, therefore, the
most polluting mode of transportation whereas sea transport remains the least polluting.
The same applies to NOx emissions.
Road transport is responsible for 51% of these pollutant emissions in the European
Union, as opposed to 12% for the other modes.
Nevertheless, the highest SO2 emissions into the atmosphere are attributable to
maritime transport. Emitting the same levels as road transport modes could only be
achieved by reducing sulphur content of marine fuels or installing exhaust gas cleaning
systems in ships.
Picture 1: Berthed ships in Palamós port (NE of Spain). The drop in cargo movements
has brought some owners to park some ships in cheaper ports. Source the authors, 2008.
This paper analyzes selected intermodal transport chains and pollutant emissions from
different power output ships, and compares them with those generated by road
transport. These emissions are then translated into environmental costs, based on
existing quantification databases. In some cases, maritime transport proves to be a better
alternative, justifying the granting of some kind of environmental bonus by the
administration to promote the sea option. The paper concludes with a brief discussion
on how to best implement this bonus to achieve a real balance between transport modes.
THE SCENARIO
In 1998, the European Union published the White Paper on Fair Payment for
Infrastructure Use: A Phased Approach to a Common Transport Infrastructure Charging
Framework in the EU COM (1998) 466, where “the user pays” and “the polluter pays”
principles were established. It was initially suggested that dues charged on vehicles
having a maximum payload of over 12 metric tonnes should be based on marginal
infrastructure costs per kilometre and marginal urban congestion costs. The first tariff
scheme for infrastructure use proposed in studies conducted in Europe like DESIRE
(2001) and INFRAS (2004) was meant to be implemented in Germany in 2003 with an
initial tariff of 0.17 €/km on all vehicle and truck units with a maximum loading
capacity exceeding 12 metric tonnes passing through or delivering goods in Germany.
However, after repeated delays, it was in 2005 that the scheme was launched with a
tariff of 0.124 €/km. In 2007 the average rate increased to 0.135 €/km and tariffs were
reviewed again in October 2008. As far as waste gas emissions are concerned, charges
depend on the exact number of kilometres travelled on paid motorway sections, number
of vehicle axes and engine class. Regarding pollutant emissions, in 1988 the European
Parliament adopted the first Euro regulation, followed by Euro II, III and IV. Euro V
and VI are increasingly stricter regulations on vehicle pollutant emissions, in particular
particle emissions and nitrogen oxides (NOx) limits. Coming into force on 1st
September 2009, Euro V establishes an 80% decrease in particle emission limits, which
implies the need for future fitting of particle filters in vehicles. Euro VI will come into
force in 2014 and impose limits of up to 68% of current levels on oxides. Maritime
transport emissions are mainly regulated by the MARPOL Conventioniii and some
specific European regulations. The new directives concerning SO2 and NOx maximum
emission levels aim to reduce these chemical compounds, which will be the weak point
of maritime transport in the future. Of all modes of transport, the maritime one is
responsible for the largest amount of SO2 emitted into the atmosphere, only to be
compensated by the use of low sulphur content fuels or exhaust gas cleaning systems.
However, sulphur emissions from maritime transport account for 6% to 12% of total
anthropogenic emissions onlyiv. Despite this scenario, in 2000 about 44% of total NOx
emissions into the atmosphere in Europe were attributable to road transport and 36% to
maritime transport (TERM 2002). Road transport is the main source of CO2 emissions,
contributing 91.7% of total EU transport greenhouse gas emissions. When including sea
shipping in a breakdown of transport-related CO2 emissions, it appears that in Europe
maritime transport accounts for only about 6% of total greenhouse gas emissions, which
explains the interest in reducing the share of road transport. Annex VI to the MARPOL
Convention and the NOx technical code amendments were approved at the Maritime
and Environment Protection Committee (MEPC) 58th session (October 2008),
following the draft amendments on prevention of air pollution from ships agreed by the
IMO Sub-Committee on Bulk and Liquid Gases (BLG) at its 12th session, held in
February 2008, and further agreed at the MEPC 57th session (April 2008).
STUDY METHODOLOGY
This section explains the methodology used to calculate the environmental impact and
the external costs, using data from REALISEv, a thematic network on short sea shipping
which provides prices of external costs from both sea and road transport.
The following criteria are considered:
a) The cost categories are divided into two:
- Environmental external costs: local air pollution, global warming and noise pollution.
- Non-environmental external costs: accidents and traffic congestion.
b) To evaluate the impact of the evolution of transport emissions, the scenario
considered is a future hypothetical improved condition where future stricter regulations
are applied, like the Euro V, to road (in force for new trucks as of September 2009) and
maritime transport, resulting in a 10% decrease in all current emissions, except for S,
SO2 and NOx.
Emissions factors
ROAD Euro V
SSS
SO2 (g/kg fuel)
0,114
30
NOx (g/kg fuel)
18,75
19,36
CO (g/kg fuel)
5,75
8,1
Nm-VOC (g/kg fuel)
2,316
2,466
PM (g/kg fuel)
0,45
6,84
CH4 (g/kg fuel)
0,095
0,099
CO2 (g/kg fuel)
3323
2853
S (g/kg fuel)
0,05
15
Table 1. Emission rates for the diesel EURO V road and sea, transport (Source: Own
based on ICF model from REALISE).
c) The cargo capacities of the selected Ro/Pax ships are considered, keeping in mind
that they are real ships serving short sea shipping traffic, as the conventional one in
Figure 1. Cargo capacity was calculated dividing the ship’s total linear capacity by 19.5
meters,vi including the number of trucks (assumed FEUs) that the ship is able to carry.
The cargo is measured in FEU (very close to trailer length) as it is the common unit of
freight in sea and road legs, assuming the container to be filled to 75% of its full
capacity. Thus, the maximum container payload of 25 tonnes (maximum total weight
allowed is 40 tonnes) is limited to 18.5 metric tonnes on average.
d) The main engine specific fuel consumption rate is strongly affected by the installed
propulsion systems, such as engine (Table 2), gear, shaft and propulsion arrangements.
Nevertheless, modern diesel engines use half the fuel consumed daily by old inefficient
steam engines with the same power outtakevii. For instance, the largest old passenger
liners, like the Olympic and the Titanic, burned 620 tonnes of coal per day at 21.7 knots
on average.viii
The main reasons for the decrease in consumption lie in the improved energy efficiency
of the fleet (note the phasing out of steam ships) and the reduction in speed and installed
power in certain types of vessels. For our purposes, we consider the hourly consumption
of each ship on the basis of 200 g/kW per hour. Because almost all ships mentioned
here are propelled by four-stroke diesel engines, the final consumption rate depends on
the main engine output and working rate.
Engine type
Diesel
Turbine oil
Turbine coal
Steam engine oil
Steam engine coal
Reported SFC in
g/kWh
200-240
290-305
700
Table 2. Specific fuel consumption for different engine and fuel types (Source Endresen
et al. A historical reconstruction of ships’ fuel consumption and emissions 2007)
Although the total fuel consumption rate depends on the engine’s maximum output, the
average power is assumed to be 85% of MCR (Maximum Continuous Rate) of installed
power. However, the average main engine load and speed vary dramatically for
different ship types. Some authors have reported an average load of 80% MCR based on
statistical data. For example, bulk carriers tend to have slightly lower average values
(72% MCR) than tankers (84% MCR). Accordingly, load can range from about 60%
MCR up to 95% MCR for the analyzed shipsix. For our purposes, the selected engine
load was fixed to 80% of engine load when sailing and 20% for time spent at ports due
to operations.x
e) The emission factors considered are taken from the REALISE database.
The following table shows the necessary data and the initial data obtained needed for
calculate the external costs.
Origin
Destination
Route
Obligatory data
Data obtained
Road unimodal distance (km)
Maritime distance (km)
Road intermodal distance (km)
Ship's Name
Linear meters
Speed of ship (in knots and km/h)
Ship's Power (kW)
Number of FEU (theoretical)
Load Factor (SHIP)
Hours of navigation by SSS
Type of ship
Fuel consumption
(kg/h)
Fuel consumption (kg/h) SHIP
Load (truck) - maximum 25 Tm
LOAD FACTOR (TRUCK)
Table 3. Calculation of initial data and results obtained for any route and any ship
The above data allow assessment of the external costs for the entire unimodal (road) and
intermodal chains in the selected route.
The expected results will be assessed on the comparison of a carried FEU by intermodal
and unimodal, modes. Of course, the ship emissions are divided by the number of trucks
while supplying the cost per FEU of the sea leg. By adding the external costs of sea
legs, the external cost of the total intermodal chain should be obtained. This value is
then compared with that of the road-only chain and the difference provides the external
cost savings (if any) per FEU and trip. Finally, these savings are divided by road
distance and the resulting figure is the economic savings per FEU and kilometre not
travelled.
Potential savings (€) per FEU
Savings (€) per FEU and road km not traveled
Table 4. Total external costs savings obtained by comparison of the unimodal and
intermodal solutions, taking the 200 g/h kW consumption rate (Source: Own, based on
pricing costs from REALISE, 2005).
In the end a database (Figure 2) with all the above calculations would allow to the user a
rapid comparison between new or existing unimodal and multimodal routes by either
selecting a vessel currently serving a Short Sea Shipping route or introducing the
necessary values for the calculation of a new ship.
Figure 2. Initial Screen of the database for the calculation of the SSS viability analysis
(Source: Own)
Further, new routes may be analysed introducing the sea and road distances, truck and
vessel load factors can be modified and data of ships under construction can be
introduced to assess the feasibility of Short Sea Shipping.
Figure 3. General report obtained of the database for the calculation of the SSS viability
analysis (Source: Own)
The possibility to propose some kind of environmental bonus by the administration to
promote the sea option will be analysed in the project.
The base hypothesis has been settles as follows:
1. Define of the existing routes which are currently exploited by European and Spanish
shipping companies and with origin and destination in several European and Spanish
ports has been conducted.
2. The minimum frequency to select a sea line is to call at least once per week in a
Spanish port.
3. Two areas where the maritime lines have similar sea and road distances has been
defined, i.e. Mediterranean and Atlantic, corresponding exactly with two of the four
defined motorways of the sea, proposed in the van Miert report (April 2003) as a
priority Project in the TEN-Txi. In this sense, we see that the defined routes in the
Atlantic Arc would be covered in the Western Europe Motorway, and the ones in the
Mediterranean Arc, would be included in the West Mediterranean motorway.
It will be assessed a correlation among all the ships, carrying out the same route ,
obtaining the most favourable condition represented by a ship and also an average to
obtain all the values offered by the considered ships. This process will be repeated in
every route, getting an average external unitary cost by carried FEU, the potential
savings by each carried FEU by sea way, and the equivalent potential saving per FEU
and road kilometre not done, by each possible route in the Atlantic and Mediterranean
arcs.
EXPECTED RESULTS FROM THE ANALYSIS
Comparison of the results obtained for each maritime zone reveals that both have rather
similar mean cost values. The mean values of average routes in the Mediterranean and
Atlantic zones are:
Average external cost savings per FEU and
kilometre of road not travelled
Mediterranean route
Atlantic route
0,24
0,21
Table 5. Average external cost savings per FEU and kilometre of road not travelled of
the Mediterranean and Atlantic routes. (Own source)
A slight advantage of the Mediterranean arc can always be observed, particularly in the
annual results since, in the case of trips, weekly frequencies increase, implying more
annual trips and greater accumulated savings. A discount calculated by multiplying the
constant found by the number of kilometres of road not travelled could be offered to
carriers covering any new Short Sea Shipping route between Spain and Europe to be
implemented or on already operating susceptible of being included in one of the above
zones. Moreover, economic and environmental costs would decline and road traffic
would be alleviated.
CONCLUSIONS AND FURTHER RESEARCH
The savings in external costs, could justify some public grants as an economic incentive
to convince the user to utilize the maritime transport.
The exact quantity of the bonus would depend on the route and ship type and could be
evaluated by the above proposed method that is, obtaining a savings figure per
kilometer not travelled by road. This figure could account for 20% of ship fares.
Moreover, fuel tire wear and driver salary and driving time costs would be reduced.
Ships should improve the operational and environmental efficiency of their engines in
order to be capable to compete with road transport.
An example is the environmental bonus offered by the Italian government in several
routes to endorse trailers and trucks boarding ships instead of covering routes by road
only. This action has also been taken by the Basque autonomous government in Spain,
which assures that the sea option has been increased by 20% in the funded lines.
i
According to La Fundación Transpirenaica. El transporte a través del Pirineo. www.transpirenaica.org.
European Commission. COM (2001) 370. European Transport Policy for 2010: Time to Decide.
Brussels
iii
Annex VI of MARPOL 73/78. (1998). Regulations for the Prevention of Air Pollution from Ships and
NOx Technical Code. IMO Publication. ISBN 928060893. London, United Kingdom.
iv Chengfeng, W. et al. (2007). The costs and benefits of reducing SO2 emissions from ships in the US
West Coastal waters. Transportation Research Part D 12.
v
Lloyd, M.; Vassallo, W. (2005). Realise Project: Regional Action for Logistical Integration of Shipping
across Europe. WP 3 – Environmental Impact Analyses. Final Report. Disponible en: http://www.realisesss.org.
vi
Trailer length is considered 19.5 meters, as stated by the EC Directive 2002 of 18th February 2002 as
maximum length for an articulated trailer of 16.5m, 1.5 meters being added between trucks.
vii
Data obtained from the Emission Inventory Guidebook (EIG) on the COPERT III calculation model
(2002).
viii
Encyclopaedia Titanic, http://www.encyclopedia-titanica.org/discus/messages/5919/6509.html
ix
Floedstroem, E. Energy and emission factors for ships in operation. KFB Rep. (1997). Swedish
Transport and Commerce Res. Board. Swedish Maritime Administration and Mariterm AB. Gothenburg.
Sweden.
x
On page 15 of the above paper, Endresen, O. explains that the fuel consumed by auxiliary engines in
ports and at sea may amount to less than 10% of installed power. We adopt a 20% figure in view of the
greater amount of electric power required by a Ro/Pax ship as that considered in our study.
xi
The Trans European Transport Network (TEN-T) has as the main goal to promote the establishment of
new freight regular connections among member states, promoting the sustainability.
ii