2.1.3. Our emergy synthesis In this study, emergy accounting is performed following the usual procedure of first diagramming the infrastructure system, then creating a comprehensive inventory of the resources involved in the system operation, and finally determining a set of indicators representing the actual investment efficiency, where the investement accounts for what provided by human economy as well as by the geobiosphere. The evaluation of the investigated civil infrastructure works is led through the comparison of the road sub-system before and after its deviation and expansion. Costs and expected benefits are assessed in terms of materials, energy, and labor respectively needed or saved, so as to provide detailed information for the evaluation of the choice already made and – above all – for responsible future policy-making. Novel indicators have been more specifically designed and calculated for transportation studies (Federici et al ., 2008, 2009), namely, the emergy per passenger-kilometer (expressed in sej/p-km) and the emergy per ton-kilometer (expressed in sej/t-km). This allows to make the emergy synthesis more suitable for decision-making recommendations, in as much the integrated sustainability of a system must be also expressed in terms of output performaces. 2.2. Case study and analyzed scenarios Our study addresses the existing case of the Italian A1 highway, linking Milan to Naples. In particular, its Apennines mountainous passage (“ Variante di valico ”) between Bologna and Florence is analyzed before and after the quite recent completion of major deviation and expansion works, namely, the “ A1 var” section, opened in December 2015 (see Figure 1). Its managing authority – the Italian leading company (Bruno, 2016) in the group of the concessionaires for public highways – has claimed that such works would let their customers save up to 100 millions liters of fuel every year (Autostrade per l’Italia, 2015), even though – to the best knowledge of the authors – details have not been published to retrace the calculations that led to such value. No consideration has been made, so far, on the social and environmental costs of the expansion works, that lasted over 10 years and costed 7 billion euros (data from Italy’s national public broadcasting company Rai -
Radiotelevisione italiana, 2015). Previous independent studies by one of the Authors (Cristiano, 2012; 2016) provide data to estimate the expected benefits and detriments of the expansion of a consecutive section of the one at issue, in terms of polluting emissions, calculated after a testing campaign in virtual reality (drive simulation) and elaborated through a dynamic model continuously computing the driving behavior of the vehicle. No significant savings in terms of pollution per unit of service (i.e., g/km per vehicle) were observed, while official EU prediction models have been found to averagely underestimate pollutant emissions. At the same time, no hint of significant savings in fuel consumption was evidenced when analyzing the differences
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- Summer '20
- Dr joseph
- Energy, Automobile, World energy resources and consumption, Highway