Eur. Transp. Res. Rev. (2012) 4:91–106 DOI 10.1007/s12544-012-0073-x ORIGINAL PAPER A heuristic method for determining CO2 efficiency in transportation planning Silvio Nocera & Federica Maino & Federico Cavallaro Received: 15 April 2011 /Accepted: 11 January 2012 /Published online: 8 February 2012 # The Author(s) 2012. This article is published with open access at SpringerLink.com Abstract 1 Introduction Background CO2 emissions are generally considered the most important indicator to determine the global warming The extent and nature of the growing traffic demand in effects. Their evaluation in the case of a transportation Europe pose several challenges for sustainable transporta- infrastructure is generally not easy and could be achieved tion, putting pressure on the decision-makers to provide new through a separate balance. facilities for both passenger and freight transportation, and Method This paper introduces a new heuristic method for hence an ever increasing strain on infrastructure planning identifying the modifications in the CO2 emission balance, policy. deriving from a variation in transportation supply. The focus The decline in railway use favours the expansion of road is predominantly on the construction and on the operational mobility and its infrastructures. In this framework the over- phases, which are listed in all their main elements. The method dependence on a limited number of routes has severe compares the maintenance of the “do-nothing” option with a impacts on certain areas, generally without adequate com- number of traffic scenarios resulting from the introduction of a pensation for the local communities, which call for meas- new infrastructure and deriving from different policy measures. ures to mitigate the negative impacts of traffic (congestion, Case-study The construction of the Brenner Base Tunnel is severe crash incidents, large amounts of land wasted and used as a case-study for the model, highlighting the role of pollution from all motorized traffic modes). an enlightened transport policy in the reduction of the CO2 Among the polluting substances, greenhouse gases emissions. (GHGs) have steadily assumed a main role. Carbon dioxide (CO2), methane (CH4), nitrogen oxides (NOx), hydrofluor- Keywords CO2 Emissions . Transportation . Heuristic . ocarbons (HFC), perfluorinated compounds (PFC), sulphur Brenner railway tunnel hexafluoride (SF6) are the most important among them [39, 51]. However, as CO2 accounts for about 90% of global S. Nocera (*) GHG emissions [12], it is often used as an overall indicator IUAV University of Venice – Research Unit “Traffic, in heuristic methods. ” Territory and Logistics , The CO2 impacts concern the three environmental, social Dorsoduro 2206, and economic dimensions of sustainability [11, 41, 50]. 30123 Venice, Italy e-mail: [email protected] Referring to the first one, CO2 becomes one of the main : : causes of the global warming [14, 39] as soon as its level S. Nocera F. Maino F. Cavallaro exceeds the threshold level of 350 parts per million by – EURAC European Academy of Bozen/Bolzano Institute volume (ppmv) [18]. The linked environmental consequen- for Regional Development and Location Management, Viale Druso 1, ces are well known: weather changes, temperature increase, 39100 Bolzano, Italy sea-level rise, harmful freeze–thaw cycles, precipitation … F. Maino changes, landslides, erosions in coastal areas etc. e-mail: [email protected] Social sustainability of CO2 impacts is normally referred F. Cavallaro to the remarkable influence of these consequences on hu- e-mail: [email protected] man life. Among them, a reduction in the agricultural 92 Eur. Transp. Res. Rev. (2012) 4:91–106 productivity and in the gross domestic product as well as a effects is hard to estimate and quantify. This is obviously a migration towards more productive areas are included, key-step, which may yield flawed results if emissions are mostly in the development countries, thus confirming that assessed using MCE. the unmitigated climate change is incompatible with sus- In order to determine the CO2 contribute to the overall tainable development [53]. Other consequences are visible impacts, a separate balance analysis is required. This meth- in the life style and in the health of humans, including heat od has already been applied in many fields, namely the strokes, cardiovascular and respiratory problems [6, 22]. industrial [13, 19, 54] as well as the biological [25], agri- Finally, the economic aspect has been treated in a vast cultural [9] and renewable energy [26] ones. amount of studies [34, 53], including some radical theories CO2 balances kindle considerable interest also within that consider the global warming as the most important transportation engineering. Von Rozycki [52] considers the market failure ever seen [42]. Hence it derives that the variation in CO2 emissions related to the introduction of the determination of the future CO2 emissions is very relevant high-speed railway line between Hanover and Würzburg. if related to the concept of sustainability and its three The study is detailed but it refers only to the environmental dimensions. footprint of the railway without considering the concurrent Even though our understanding of the physical mecha- trend in road traffic. Tuchschmid [49] proposes a method to nisms of the climate system has progressed rapidly, the use quantify the emissions of several pollutant gases (including of this knowledge to support transportation decision mak- CO2) from the construction of high-speed lines in Europe. ing, manage risks, and engage stakeholders is still inade- Being based on macro-scenarios at European level, the quate [45, 48]. Indeed, expressing global warming in study assumes appropriate simplifications at such a scale, monetary terms requires providing a consistent estimation which however make the method inapplicable at infrastruc- of the effects of higher temperatures within the well-known ture level. An interesting study is carried out to compare the uncertainty of linking CO2 and environmental damage. emissions of CO2eq of the high-speed and traditional railway This is the biggest issue in dealing with global warming lines connecting London to locations in the North and West and the very aspect that sets it apart from other external of the United Kingdom [31]. Results are based on scenarios costs (such as air and noise pollution). As known, the latter for 2070. Also in this case the study dwells on the railway are generally converted into monetary units which are alone without considering the consequences that the new purported to express health expenses, property value re- line could have on the road traffic. duction and other possible costs. Due to this, traditional Booz Allen Hamilton Ltd. [8] introduces a balance which techniques for monetization hardly apply to the context of compares the CO2 emissions deriving from the London- CO2. Edinburgh and the London-Manchester high speed lines Quantifying CO2 impacts through the Net Present Value with their corresponding air lines over a period of 60 years. (NPV) is challenging, since impacts are difficult to estimate The forecast of the CO2 emissions is provided by the calcu- and their apportionment on an annual basis is problematical lation deriving from the construction and the operation to apply. Moreover, no distinction between who receives phases, the latter being based on the emissions module benefits and to whom costs incur can normally be made, (i.e. the forecast of future specific emissions) and the thus potentially waiving the principle of social equity (some demand module (i.e. the forecast of future demand). segments of the community might receive all benefits at the Finally, the engineering company of the Italian State expense of others). A successful attempt of estimating the Railways [23] proposes a method to forecast the CO2 emis- impacts of greenhouse gas reduction policies through sions that would be generated by a new railway line between the use of the Benefit-Cost Analysis (BCA) is the use of Rho and Gallarate. This study is based on well-defined the MERGE model [7]: the determination of the overall technical and regulatory assumptions and takes into account national production of GHGs and other polluting gases in various stages of the project (preliminary, final, execution, different scenarios with this method showing the effective- “as built” phases). However, since it lacks a clear descrip- ness of a policy that internalizes the costs of the global tion of the methodology, it can hardly be applied elsewhere. climate change and the local air pollution. All the afore-mentioned studies being recent, the current The Multi-Criteria Evaluation (MCE) is a promising ap- interest in the issue among infrastructural planners is con- proach when there are significant non-monetary and non- firmed. Nonetheless, most of the methods quoted do not monetisable benefit-and-cost components to a proposed pol- seem flexible enough to be used for assessing the carbon icy or project [11, 27, 28, 36]. This is also the case with footprint of different transportation systems. GHGs and in particular with CO2. However, the assessment This paper presents a new heuristic method to that end of the relative level of importance (usually referred to as (thoroughly described in section 2), which will be tested on “weight”) of GHGs with respect to other criteria is normally the Brenner Base Tunnel (BBT) currently under construction an issue, because the link between emissions and global (section 3). Eur. Transp. Res. Rev. (2012) 4:91–106 93 2CO2 balance: description of the method emissions. The balance presented should however be ap- plied to a larger amount of cases to make this conclusion ACO2 balance is an analysis intended to assess the impact of a generalizable. For this reason, the impacts of the construc- given project or activity over time, for the purpose of climate tion phase are examined in short in section 2.2 of this paper. protection and the prevention of detrimental effects on human In this framework, since construction is not to be consid- health.