Technical University of Crete (TUC), School of Production Engineering and Management (SPEM), Chania, Greece. a

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1 Development and implementation of Life Cycle Assessment (LCA) for the supply and transportation of widely used liquid fuels in different geographical boundaries G. Papadakis a, S. Papaioannou, E. Vangeloglou, P. Machaira Technical University of Crete (TUC), School of Production Engineering and Management (SPEM), Chania, Greece. a TUC, SPEM, University Campus, Chania, Crete, Greece Tel: , gpap@dpem.tuc.gr Key words: Life Cycle Analysis, fuels supply, Life Cycle stages, environmental impacts, emissions ABSTRACT Emissions of fuels in their supply chain may have significant impact to man and the environment. The present study focuses on the life cycle of Gasoline and Diesel as examples of commonly consumed fuels in fixed geographical boundaries, considering actual demand scenarios and transportation modes. The emissions of products when evaluated during their Life Cycle stages, predict the expected environmental impact from different transportation modes. Six Life Cycle (LC) stages of fuels are identified using one metric tonne as their common functional unit: Loading, Unloading, Transportation, Temporary Storage, Distribution and delivery to End Users. For the development of the LCA models, the supply characteristics (participation rates) of fuels in the Greek geographical boundaries are considered as case studies. The overall environmental impact and impact category indicators are calculated for the normal emissions, examined as product releases (excluding accidental releases), in comparison with the emissions from fuel combustion and energy consumption. When the product releases are only considered, Gasoline and Diesel emissions of Sea Transportation show increased environmental impact underlining the respiration of organics. When combustion engines are encountered, greenhouse gas emissions caused during Road Transportation exhibit even higher impact with adverse effects from respiration of inorganics. The Sensitivity Analysis performed under large variations in participation rates of LC stages, shows that Sea and Road Transportation remain the main contributors to the overall impact of life cycles. The results of the present LCA case studies can be applied to a wide range of regional, national or even international areas with different geographical characteristics and product supply chains for the modes examined. The outcomes of the present study can support improvements in the relevant regulatory frameworks and can facilitate recommendations in guidelines, good industrial practices and procedures, in an effort to reduce the impact of fuel releases to vulnerable receptors. 1. INTRODUCTION As environmental awareness increases, the environmental performance of products and processes has become a key issue. Every product has a life which starts with its design/development phase and finishes with end-of-life activities. Throughout product s life the

2 following phases could be identified: Raw Material Acquisition, Processing and Manufacturing, Distribution and Transportation, Use, Reuse, and Maintenance, Recycle and Waste Management. During the lifetime of a product, all activities and processes have environmental impacts due to consumption of resources, emissions of substances in the natural environment, and other environmental exchanges. The methodological framework for estimating and assessing the environmental aspects/impacts associated with a product over its life cycle is Life Cycle Assessment (LCA) (ISO 14040, 2006a). A detailed review of ~ past accidents (PROTEAS LIFE+ Project, ) involving dangerous substances concluded that road transport and loading/unloading of flammable liquids (hazard class 3) and flammable toxic gases (hazard class 2) have a substantial contribution to accidents with high-impact casualties. Among all dangerous products, gasoline and diesel exhibited the highest risk related to human casualties. Concerning environmental effects, it was reported that relatively small spills of chemicals could have considerable environmental impact but this could not be historically related to petrochemical products. In addition, the analysis showed that large volume spills of environmentally dangerous substances to the aquatic environment occurred at relatively lower frequency than that of incidents with human casualties. Risk indices applied to those cases should rather pay attention to the extent and type of consequences than to the frequency of the spills. Due to the high production and consumption of fuels and petrochemical products, there are studies examining and assessing their impact to health and the environment. Some of these studies used LCA tools in order to assess fuels environmental profile giving emphasis to greenhouse gas (GHG) emissions of fuel production (Spartali et al., 2010; Singh et al., 2010), while some others performed a well-to-wheel (WTW) life cycle analysis including fuel production and use (Morales et al., 2015; Rahman et al., 2015; Restianti and Gheewala, 2012). Rahman et al. (2015) quantified the WTW life cycle GHG emissions for transportation fuels derived from five North American crude oils considering the following life cycle stages: recovery of crude, crude transportation, refining of crude, finished fuel transportation, combustion of transportation fuels in vehicle engines. They concluded that gasoline had higher GHG emissions than both diesel and jet fuel, mainly due to the stage of combustion but also due to the resulting GHG emissions from gasoline production in the refinery. Apart from the quantification of GHG emissions of Gasoline WTW life cycle, which includes the five subsystems of crude oil extraction, gasoline importation, refinery, gasoline storage and distribution/use, Morales et al. (2015) studied the environmental impact indicators such as acidification, eutrophication and ecotoxicity showing that the stages of refinery and distribution/use played the major role to the impact categories showing mainly contribution to climate change (due to CO 2 emissions) as well as ozone depletion. Based on the authors, climate change impact could be attributed to the use of gasoline in cars as well as the refining activities related to the use of fuel oil and natural gas in the stream production process. Similarly, Restianti and Gheewala (2012) analyzed gasoline WTW life cycle in Indonesia and showed that end-use combustion was the main contributor to global warming. However, although the majority of fuel life cycle studies deal with GHG emissions related to fuel combustion and other processes, there are no studies on Supply and Transportation fuel chain focusing on the environmental impact of product s emissions and releases when transported or stored without giving emphasis on vehicle engines process, as

3 well as on the relation of its environmental profile with the different modes of each life cycle stage. The present study aims at performing an environmental analysis of the main Supply and Transportation cycle of Gasoline and Diesel, fuels which are widely used in Greece and most other countries. The Life Cycle Assessment (LCA) methodology adopted supports the implementation of Health, Safety and Environment (HSE) regulations on Hazardous Chemicals (HazChem) to reduce health and environmental consequences from emissions and releases of such hazardous substances to vulnerable receptors. Analysis was based on two distinct approaches: in the first approach, emphasis was given to the emissions and releases of the product transported and supplied under normal conditions without considering the fuel and energy consumption involved, while in the other, the combustion of transportation fuels in vehicle engines along with the energy consumption were examined. Based on the performed case studies, certain coefficients, characteristic to each Life Cycle (LC) stage in Greece, were deduced and the effects to the environment and the public health and safety were delineated. A comprehensive and transparent environmental profile of the targeted fuels, on the basis of the environmental impact assessment of the emissions and spills during LC Stages, will set the springboard so as specifications to be developed and recommended actions to be identified as guidelines for the improvement of the existing practices and procedures. 2. MATERIAL AND METHODS 2.1 Methodology The basic principle behind LCA is the modelling process by which the practitioner tries to describe as realistically as possible a system. Typically, a system is a static simulation model, consisting of unit processes, each representing one or several activities e.g. production, transportation, etc. For each unit process, there are inputs (resources, emissions, and environmental exchanges) and intermediate product flows that link the several unit processes (reference flows: the amounts of specific product flows for each of the compared systems required to produce one unit of the function). The reference flow then becomes the starting point for building the necessary models of the product systems. According to ISO (2006), a product system is a collection of unit processes, each representing one or several activities, linked to one another by flows of intermediate products and/or waste for treatment. The product system can also be connected to other product systems via product flows across the system boundaries (either into the system or out of the system). The unit processes are linked to the environment by elementary flows, which are any material or energy entering the system being studied. The system has been drawn from the environment without previous transformation or leaving the system being studied and discarded into the environment without subsequent transformation. The main objective of this study was to assess the environmental impact of Gasoline and Diesel life cycle in Greece applying the LCA methodology and focusing on the Supply and Transportation product chain; from the product loading bay to a mode of transport in the refinery unit until delivery to end user. Following the ISO (2006) methodology, the

4 functional unit shall be defined based on the relevant function of the product. The functional unit is a measure of the function of the studied system and it provides a reference to which the inputs and outputs can be related. This allows normalisation, in a mathematical sense, of all extractions and emissions for a single product or between products and enables comparison of two essential different systems. Therefore, an appropriate functional unit for this study would be fuels to fulfil the needs of one intermediate or end user for a specific amount of time. For practicality reasons, in the current LCA study the use of a reference flow of One Metric Tonne (1 MT) of HazChem, which is equal to 1,000 kg of a specific substance or product, was used. The SimaPro 8 (Prè-Consultants, 2013) software and the Ecoinvent database version 3.0 (Prè- Consultants, 2013; Spielman et al., 2007; Frischknecht et al., 2005) were used in the present LCA study. SimaPro is a widely applied and validated LCA tool while Ecoinvent database (v3.0) includes over 10,000 up-to-date processes, covering a broad range of processes, such as electricity production, transport, and materials, such as fuels and chemicals. Finally, the calculation of environmental impacts was performed using the EcoIndicator 99 Methodology (Prè-Consultants, 2001). 2.2 System Boundaries and Case Studies Description of System Boundaries and Assumptions System boundaries determine which unit processes shall be included in the LCA study and therefore separate the system from the rest of the world. Defining system boundaries is partly based on a subjective choice, made during the scope phase when the boundaries are initially set. The System Boundaries of the models include the Life Cycle (LC) stages of Loading [Load.], Unloading [Unload.], Transportation [Trans.], Temporary Storage [T.Storage], Distribution [Distr.] and End Users [E.User] (Figure 1). For each model, the participation rates of LC stages were defined based on data gathered from various industries and national statistical documents Figure 1: Supply and Transportation Life Cycles of widely used fuels in Greece.

5 Gasoline Life Cycle was considered to start from the gate of the tank that Gasoline is stored in the refinery (Gasoline Life Cycle system is depicted in Fig. 2 and 3). Since Greece consists of mainland and many islands, Gasoline is assumed to be transported from the refinery to a temporary storage or the end user primarily by trucks and ships and secondary by rail and pipelines. System boundaries include truck, ship, rail truck and pipeline loading from the refinery tank to the corresponding mode of transport and then the transportation by truck, ship, rail truck and pipe and unloading to a temporary storage tank. Another LC stage considered was the Gasoline distribution from the temporary storage to the service station and finally the vehicle refueling to end users. Moreover, Gasoline direct distribution from the refinery to service station was also taken into account. In a next step, a thorough review of national specific data, provided evidence for the following assumptions: In all types of Loading between the storage tank and the mode of transport, a Vapor Recovery Unit (VRU) is included; About half of the total Gasoline production in Greece is exported by Ships, whose capacities are > DWT, while for ship distribution within Greece smaller capacity vessels could be used; Road transportation and distribution take place with 32-tonne and 16-tonne road trucks; Temporary storage tanks of Gasoline have normally permanent fixed roof with an internal floating roof (Internal floating roof tanks - IFR Tanks); and In Service Stations, Gasoline is normally stored in underground tanks. Referring to Diesel, its Life Cycle system, depicted in Fig. 4 and 5, includes loading from the refinery s tank to truck, ship, rail truck or/and pipe transportation to the temporary storage tanks and distribution to service stations. Delivery to end users takes place by refueling the vehicle with diesel automotive or delivering/unloading diesel heating. Vapor Recovery Unit (VRU) is assumed to be included in all types of Loading / Unloading apart from the unloading to Service Station. Diesel temporary storage tanks are assumed to have fixed roof whereas in Service Stations the storage of Diesel to take place in underground tanks. The modes of transport and distribution in Diesel LC system are expected to have relevant capacity with those of Gasoline LC system. For both Gasoline and Diesel, an analysis was performed using available national (Greek) specific data in order to quantify the individual stages and their contribution to the overall life cycle in geographical boundaries of Greece. Fig. 3 and 5 present the contribution (participation rate) of each LC stage to the overall Life Cycle of Gasoline and Diesel, respectively. Since some LC stages exhibit multiple appearances in the defined life cycle, their participation rate to the overall life cycle surpass the value 1.

6 Figure 2: Supply and Transportation Life Cycle of Gasoline in Greece including the LC stages of Loading, Unloading, Transportation, Distribution, Temporary Storage and End Users Figure 3: Participation rate of each LC stage to the overall Gasoline Life Cycle for 1 Mt supply.

7 Figure 4: Supply and Transportation Life Cycle of Diesel in Greece including the LC stages of Loading, Unloading, Transportation, Distribution, Temporary Storage and End Users Figure 5: Participation rate of each LC stage to the overall Diesel Life Cycle for 1 Mt supply. According to the typical breakdowns of Gasoline and Diesel, truck usage is dominant (rate = 0.9 to 1) in loading and unloading operations but also in the distribution of those fuels (see Fig. 3 and 5). Ship is highlighted as the most widely used mode of transportation in Greece (0.55) in comparison of other modes. Temporary storage exhibits high contribution (0.79 to 0.95) for both fuels. Gasoline, as expected, shows high participation (0.95) in vehicle refueling. At the bottom end, pipelines and rail as scarcely used modes of conveying Gasoline and Diesel in Greece, show very low contribution (0.05 to 0.1). The above overall picture reflects the particularities of morphology and of fuels supply chain characteristics in Greece.

8 Case Studies (Only-Product and Energy-Operation models) In order to provide an environmental profile of the selected fuels in Greece, two different Case Studies for each product were developed, all referring to normal operations: the first investigates the effects of product emissions or releases (for each LC stage) to human health and the environment ( O.P. Only Product model), while the second ( E-O Energy- Operation model) examines the aggregated effects of Only Product emissions or releases together with those arising from fossil-based energy generation, the use (electricity / energy generation) and the releases due to the combustion engines in the whole supply chain. In E-O Energy-Operation models energy consumption is assumed in loading, unloading and end users operations. Energy consumption in transportation, temporary storage and distribution is assumed negligible for all modes. Fuel consumption is assumed in transportation and distribution. Emissions and releases due to the combustion engines include direct airborne emissions of gaseous substances, particulate matters and heavy metals emissions to soil and water. Gasoline LC models can be assumed as representative for all Naphtha LC models, due to their similar physicochemical properties (e.g. volatility), while Diesel LC models as representative for models of Kerosene, Aviation Fuel and Fuel Oil No.3, for the same reasons. 2.3 Life Cycle Inventories Qualitative and quantitative data on inputs and outputs were collected for each unit process within the defined system boundaries. Case-specific primary data define the foreground processes while more general information the background processes. Foreground processes data were collected through surveys with questionnaires, technical registration sheets, sitevisits in installations, on-site measurements and laboratory analyses of aquatic, solid and air samples. For the Background processes data, available literature and industrial sources were used: on estimation techniques for emissions and releases i.e. EPA, 1995, 1999, 2006, 2008; CONCAWE, 2006, 2009; Denmark National Environmental Research Institute, 2009; Texas Natural Resource Conservation Commission Memorandum, 1997; Lewis, 1997, literature published sources, such as industry data reports, laboratory test results, governmental documents and reports, reference books, previous life cycle inventory studies, equipment and process specifications, as well as the Ecoinvent database version 3.0 of SimaPro 8 software which was used for the LCA development. Relevant inputs and outputs of the fuels were based on their properties and their typical compositions in Greece. Gasoline, as a product with high volatility, was assumed that in case of product release from a critical equipment, it would evaporate as Volatile Organic Compounds (VOCs) and specifically as Aliphatic Alkanes, Aliphatic Unsaturated Hydrocarbons, Benzene, Toluene, Xylenes, other Aromatic Hydrocarbons and MTBE. In case of Diesel, release from a critical equipment to the environment, different pathways of releases can be assumed due to its moderate volatility. If Diesel is released to air, the airborne product is regarded as VOCs (CONCAWE 1996, 2001; Ministry of Land, Water, Air Protection, British Columbia, 2001). If the release is on water, the thin layer that will be formed on water surface, due to generally low solubility, will evaporate, while a part will remain in water and

9 most of the components will partition to sediment. In case of Diesel release on land, the whole quantity of release is assumed to remain on soil due to its low evaporation rates. According to the typical composition of Diesel produced in Greece, chemical compounds such as Aliphatic Alkanes, Benzene, Toluene, Xylenes, other Aromatic Hydrocarbons and PAHs, are assumed to be released. The combustion of fuels in vehicle engines in the supply chain was examined by using the Ecoinvent database and analyzing CO 2, CO, NO x, SO 2, CH 4 and Hydrocarbon gases. For all model flows, One Metric Tonne (1 MT) was used as the reference amount of inventory mass. For inventories processes related to transportation and distribution, One Metric Tonne x Kilometer (1 MT km) was the used as the reference measure estimated on the average distances covered by the relevant means in Greece, e.g. 200km for truck, 600 km for ship etc. (see Tables 1 and 2). Typical inventories data for 1 MT of Gasoline and Diesel conveyed in Greece are presented in Tables 1 and 2 respectively. The participation of each LC stage mode to the overall product Life Cycle is presented as rate of 1 MT of product. In cases, participation rate exceeds the value 1 since the particular mode is met several times in the whole Life Cycle. Under the above configuration, remarkable high emissions to air are deduced for Gasoline only at vehicle refueling, at temporary storage of service stations and ship loading / unloading stages (see Table 1). Energy consumption in transportation, temporary storage and distribution is assumed negligible for all modes. Life Cycle Inventory data including the rates, the emissions and typical characteristics of each LC stage in Gasoline Life Cycle LC stage GASOLINE LIFE CYCLE TRANSPORTATION LOADING UNLOADING TEMPORARY STORAGE DISTRIBUTION END USER LC stage mode Participation rate of mode in the total GASOLINE Life Cycle Emissions to air (g VOCs / MT Gasoline) Typical Distance (Km) Energy generation (KWh) Pipeline Rail Ship Truck Rail Ship Truck Rail Ship Truck Apart from Service Stations Service Stations Ship Truck Vehicle Refueling Table 1: Life Cycle Inventory data for 1 MT of Gasoline for each LC stage and LC stage mode.

10 Life Cycle Inventory data including the rates, the emissions and typical characteristics of each LC stage in Diesel Life Cycle Releases Releases DIESEL Participation Emissions to water to soil to air Typical Energy LIFE CYCLE rate in total (g Diesel (g Diesel (g VOCs / Distance generation released / released / LC stage DIESEL MT (Km) (KWh) LC stage MT MT Diesel) mode Life Cycle Diesel) Diesel) TRANSPORTA TION LOADING UNLOADING TEMPORARY STORAGE Pipeline Rail 1.4* Ship , Truck * Rail Ship Truck *10-2 g * Rail 1.1* Ship Truck Apart from Serv. Station Service Station DISTRIBUTIO Ship N Truck * Vehicle Refueling *10-2 g ** END USER Delivery to End Users ,8*10-1 g ** * standard release at service station ** standard release during unloading Table 2: Life Cycle Inventory data for 1 MT of Diesel for each LC stage and LC stage mode. 3. RESULTS AND DISCUSSION 3.1 Life Cycle Assessment The results concern the Life Cycle Assessment which was performed for each product under examination, the particular system boundaries, the product supply chain within a specific geographical area and the individual case-study models (assumptions). All case studies were considered under the same system boundaries, the supply chain characteristics of the same geographical area and for the same set of models (OP: Only Product and EO: Energy

11 Operation). This way, different products were compared with respect to their overall environmental impact but also to the type of impact posed by different transport mode, LC stage along the whole supply chain. Table 3 shows the contribution of each LC stage to the overall environmental impact assessment which has been calculated for the individual product systems and separately for the O.P. (Only Product) and E-O (Energy Operation) models. For both products and models examined in different LC stages, it is shown that transportation overall (by any mode, i.e. pipeline, rail, ship, road) as compared with other LC stages (e.g. loading, unloading, temporary storage, distribution, end users), exhibited the highest environmental impact, 58.9 % to 89.6 %. Table 4 exhibits the contribution of fuel combustion and energy consumption to the overall environmental impact assessment, underling fuel combustion during road transportation as the main contributor to the overall impact (61.4 to 68.1 %). Contribution (%) of each LC stage (and mode) to the OVERALL IMPACT for 1 MT of product LC stages and modes O.P. Only-Product model E-O Energy-Operation model Gasoline Diesel Gasoline Diesel LOADING < Truck Loading < 1 < 1 < 1 2,5 Ship Loading < < 1 < 1 Rail Loading < 1 < 1 < 1 < 1 TRANSPORTATION Road Transportation 2.8 < Sea Transportation Pipeline Transportation < 1 < 1 < 1 < 1 Rail Transportation 1.2 < UNLOADING < Truck Unloading < 1 < 1 < Ship Unloading < < 1 < 1 Rail Unloading < 1 < 1 < 1 < 1 TEMPORARY STORAGE < 1 < 1 < 1 < 1 Storage in Service Station < 1 < 1 < 1 < 1 Storage apart from Service < 1 < 1 < 1 < 1 Station DISTRIBUTION Road Distribution 1.8 < Sea Distribution < END USERS 5.9 < < 1 Vehicle Refuelling 5.9 < < 1 Delivery to End Users - < 1 - < 1 Table 3: Contribution of each LC stage to the overall environmental impact assessment of Gasoline and Diesel life cycle systems

12 Contribution (%) energy consumption and fuel combustion to the OVERALL IMPACT for 1 MT of product Energy / Fuel O.P. Only-Product model E-O Energy-Operation model Consumption Gasoline Diesel Gasoline Diesel Energy Consumption Electricity Fuel Combustion 32 tonne Truck tonne Truck < DWT Tanker > DWT Tanker Train Truck Table 4: Contribution of energy consumption and fuel combustion to the overall environmental impact assessment of Gasoline and Diesel life cycle systems For the different type of impact to Human Health, Ecosystem Quality and Resources different impact categories indicators were selected that fit to the particular impact characteristics per impact type. The impact categories indicators considered are: Carcinogens [C] Respiration of Organics [RO] Respiration of Inorganics [RI] Climate Change [CC] Radiation [R] Ozone Layer [OL] Ecotoxicity [E] Accidification/Eutrophication [AE] Land Use [LU] Minerals [M], and Fossil Fuels [FF] The contribution of each LC stage to the individual impact categories has been estimated for Gasoline and Diesel. The results are presented in Figure 6 per LC stage and mode for the two models (PO: Only-Product and EO: Energy-Operation). It is thus possible to extract conclusions on relevant impact of individual LC stage or mode by comparing the level of individual impact categories indicators (expressed in Pt: Eco-indicator points, dimensionless measure indicative for one thousandth of the yearly environmental load of one average European inhabitant). The Eco-indicator value of 1 Pt was calculated as the ratio of the total European environmental load to the number of inhabitants, multiplied by 1000 (scale factor).

13 Pt 2 1,5 1 0,5 0 Pt 2 1,5 1 0,5 0 C RO RI CC E AE C RO RI CC E AE 348 A. GASOLINE (O.P.) B. GASOLINE (E-O) Pt 0,04 0,03 0,02 0,01 0,00 Pt 1,5 1 0,5 0 C RO RI CC E AE C RO RI CC E AE C. DIESEL (O.P.) D. DIESEL (E-O) Figure 6: Product LC Stages contribution (x-axis) to impact categories (z-axis) for LC models: A. Gasoline (O.P.), B. Gasoline (E-O), C. Diesel (O.P.), D. Diesel (E-O) Concerning Gasoline and O-P model Only-Product, the LC stage with the highest contribution (85.5 %) to the overall impact was Sea Transportation (see Table 3 and Figure 6.A : Gasoline O.P. model). This may be due to the high participation of tankers transportation, the long distances covered by tankers and the high VOCs emissions realised in ship transportation (see Tables 1 and 2, transportation ship). In contrast, Road, Rail and Pipeline Transportation exhibited much lower contribution (2.83 %, 1.23 % and <1 % respectively) to the overall impact. Vehicle refuelling with Gasoline at service stations showed a contribution of 5.9 % while road and sea distribution only 2.9 %. For Gasoline and O-P model, the most significant environmental impact category was Respiration of Organics (see Fig. 6.A) mainly originated in Transportation (1 Pt) and partially in End users activities (0.1 Pt). The second most important impact category was Carcinogens originated in Transportation (0.1 Pt) and slightly in Loading and Unloading (1*10-2 Pt). Concerning Gasoline and E-O Energy-Operation model, the contribution of LC stages to the overall impact of Gasoline life cycle was different compared to the O.P. model due to energy consumption and fuel combustion by the vehicle engines. As a result, Road Transportation

14 contributed to the overall impact by 46.2 % while the total contribution of Transportation LC stage, considering all modes, was 72 %. In this case, Sea Transportation contributed to the overall impact by only 24.2 %. By comparing E-O with O.P. model in Gasoline, the Distribution LC stage showed an increase of 24.2 % caused mainly by Road Distribution (23.4 %). The main activity responsible for the increased contribution of Road (Transportation and Distribution) was the fuel consumption by Road Trucks (32-t & 16-t) considered in these LC stages, whose contributions surpass 61 % and 7 % of the total impact (Table 3, Figure 6.B). It should be highlighted that the impact category mostly affected when energy is considered (Gasoline E-O model) was the Human Health, and specifically the Respiration (of Inorganics & Organics), mainly attributed to the Transportation (2 and 1 Pt for RI and RO respectively) as well as, the Distribution (0.9 and 3*10-2 Pt for RI and RO respectively) operations. Combustion engines were the reason why Respiration of Inorganics was present in high levels. The most severe environmental impact category indicators, of which Ecosystem quality is affected, were Climate Change, Acidification/Eutrophication and Ecotoxicity caused mainly by Transportation LC stage ( Pt). Concerning the Diesel O.P. model (Table 3, Fig. 6.C), the allocation of LC stages contribution to the overall impact of Diesel life cycle was similar to those of Gasoline O.P. model. Sea Transportation was the main contributor (71.7 %), followed by Ship Distribution (8.8 %) and Ship Loading & Unloading (10.3 & 8.1 % respectively). The higher contribution value of Ship Loading compared to that of Ship Unloading can be attributed to the different participation rates of theses LC stages. Diesel O.P. model produces Respiration of Organics and Carcinogenicity however, the impact was insignificant (< 10-2 Pt) compared to impacts of Gasoline Life Cycle in both O.P and E-O models. Concerning Respiration of Organics, the LC stage with the main contribution was Transportation while Loading / Unloading were responsible for Carcinogenicity. The emissions due to fuel combustion of Road Trucks and Ship Tankers were the dominant reason why Transportation (58.9 %) and Distribution (36.9 %) were the main contributors to the overall impact of Diesel E-O model. The fuel consumption of 32-t Road Truck played the major role (68.1 %) followed by 16-t Road Truck Fuel Consumption (14.8 %) and Tankers Fuel Consumption (8.3 %). Loading and Unloading operations had a low contribution probably attributed to electricity / energy consumption (4.27 %). The contribution of truck engines fuel consumption appears clearly in Figure 6.D where the impact categories indicators with the highest values were related to GHG emissions (Respiration of Inorganics, Climate Change, etc.). In particular, Respiration of Inorganics value originated by Transportation (1.4 Pt) and Distribution (0.9 Pt) LC stages was extremely high compared to Respiration of Organics (< 0.01 Pt). Unlike Respiration of Inorganics, Respiration of Organics could not be related to fuel combustions and could possibly be attributed to Diesel emissions and leakage. Apart from Respiration of Inorganics, GHG emissions during Transportation and Distribution were responsible for Climate Change ( Pt), Ecotoxicity (< 0.08 Pt), Acidification/Eutrophication (< 0.13 Pt) and Carcinogens. In conclusion, comparing O.P. and E-O models, the present study showed that even if the main contributor to the environmental impacts came from the product emissions during Sea Transportation (O.P. models), the GHG emissions during Road Transportation played finally, the

15 key role to the overall impacts of the life cycles when vehicle fuel combustion was considered (E-O models). In addition, E-O models showed the highest contribution to the impact categories and specifically to the Respiration of Inorganics impacts ( Pt) while O.P. models were responsible for Respiration of Organics impacts (<1.2 Pt). Most of past studies focus on quantifying GHG emissions and energetic requirements related to fuel production and use while a few studies examine further other parameters such as Toxicity, Climate Change, etc. Morales et al. (2015) studied Gasoline LCA in Chile by using 1 km driven distance by a passenger car, as functional unit. They divided the selected system boundaries into the following subsystems: crude oil extraction, gasoline importation, refinery, gasoline storage and distribution and use as vehicle fuel. The authors concluded that GHG emissions during distribution (referred to as transportation in the present study) and use were responsible for the 50 % of Climate Change impact, while the respective percentage for the refinery stage was 40 %. This is in good agreement with the results of the present study, as mentioned above, when fuel consumption is considered. Based on their findings (Morales et al. 2015), fuel combustion in vehicles during distribution and use was responsible for the presence of further impact categories indicators such as ecotoxicity and acidification / eutrophication. Such conclusion cannot clearly substantiated form the results of the present study. Other impact categories indicators, such as ozone depletion and human toxicity, were related to refining activities and transportation of crude oil. In addition, Restianti and Gheewala (2012) also studied WTW of Gasoline life cycle, using 1 m 3 of Gasoline, as a base. The outcome of their study was that production LC stage and use of gasoline as vehicle engine fuel contributed mostly to the environmental profile by affecting climate change due to GHG emissions. In fact, the results of the present study support such conclusion, since Gasoline in the E-O model exhibits distinguishable impact to the category of Climate Change. 3.2 Sensitivity analysis In order to examine the behavior of the aforementioned LCA Case Studies in boundaries of different geographical areas, a sensitivity analysis test was conducted, aiming at determining how sensitive the developed LCA models were to variations of their input parameters and their structure. The sensitivity analysis test was performed by varying input parameter values and obtaining the resulting effects under such modifications to the dynamic behavior of the stocks (Breierova and Choudhari, 2001). The selected parameters were: - the level of participation rate for LC stages with the most significant environmental impacts in the Case Studies. This way, different regional areas of a country or even different countries can be simulated represented by specific sets of geographical characteristics and product life cycle models. - the LC stages with the highest contribution to the overall impact, namely Sea and Road Transportation for Gasoline Life Cycle and Sea and Road Transportation and Sea Distribution for Diesel Life Cycle. The results of sensitivity analysis are presented in Figures 7 A to D.

16 Contribution of Gasoline LC stages with highest severity to LCA model (%) Concerning Gasoline in the O-P life cycle model (Fig. 7.A), it is noted that for a significant decrease (from 0.55 down to 0.05) in participation of the Sea Transportation and the relevant increase of Road Transportation (from 0.23 to 0.57), Sea Transportation remained the predominant contributor to the total environmental impact even if its contribution decreased significantly (from ~ 85 % to ~ 30 %). At low participation levels of Sea Transportation, the contributions of Road Transportation and Vehicle Refueling to the total environmental impact were becoming noticeable (~ 25% ). Concerning Gasoline in the E-O life cycle model (Fig. 7.B), a similar decrease (from 0.55 down to 0.05) of Sea Transportation participation rate resulted in a significant increase of the Road Transportation contribution (from 46% to 88%) remaining the predominant impact contributor. It is noted that the participation increase of Road Transportation was responsible for more GHG emissions of combustion engines of large road trucks. Concerning Diesel in the O-P life cycle model (Fig. 7.C), in any decrease in participation of Sea Transportation (from 0.55 to 0.05) and Distribution (from 0.15 to ) and relevant increase of Road Distribution (from 0.15 to 0.45), Sea Transportation remained almost unchanged in contribution to the overall impact (~70%). The same applies to Ship Loading, Sea Distribution and Ship Unloading (~10%). It can thus be concluded that Diesel emissions during Sea Transportation can be considered as the predominant contributor to overall impact for many geographical areas characteristics. Finally, concerning Diesel in the E-O life cycle model (Fig. 7.D), any increase in participation of Road Transportation (from 0.15 to 0.45) causes a significant increase (from 49% to 78%) in the contribution of Road Transportation in the overall environmental impact probably due to the extra GHG emissions created during fuel consumption of larger road trucks. The above results indicate that - under large variations in participation rates of LC stages, Sea and Road Transportation remained the main contributors to the overall impact of life cycles, and - the results of the present LCA case studies are applicable to a wide range of regional, national or even international areas with different geographical and product supply characteristics A. GASOLINE (O.P.) Sensitivity Analysis LC stage participation to the overall life cycle model Sea Transportation Road Transportation Road Distribution Vehicle Refueling Sea Transportation Road Transportation

17 Contribution of Diesel LC stages with the highest severity to LCA model (%) Contribution of Diesel LC stages with the highest severity to LCA model (%) Contribution of Gasoline LC stages with the highest severity tolca model (%) B. GASOLINE (E-O) Sensitivity Analysis Sea Transportation Road Transportation Road Distribution Sea Transportation Road Transportation 487 LC stage participation to the overall life cycle model C. DIESEL (O.P.) Sensitivity Analysis Sea Transportation Ship Loading Sea Distribution Ship Unloading Sea Transportation Road Transportation LC stage participation to the overall life cycle model Sea Distribution D. DIESEL (E-O) Sensitivity Analysis LC stage participation to the overall life cycle model Road Transportation Road Distribution Sea Transportation Rail Transportation Sea Transportation Road Transportation Sea Distribution Figure 7: Sensitivity Analysis of LC models: A. Gasoline (O.P.), B. Gasoline (E-O), C. Diesel (O.P.), D. Diesel (E-O), by examining the contribution of LC Stages with the highest severity to LCA model according to different LC stage participation rates to the overall life cycle model.

18 CONCLUSIONS Gasoline and Diesel life cycles in Greece were assessed, investigating products emissions and releases as well as fuel combustions and energy consumption under normal conditions. Emphasis was given to Supply and Transportation procedures and specifically to the following Life Cycle stages: Loading, Transportation, Unloading, Temporary Storage, Distribution and End User. Among all life cycles examined, Transportation stage exhibited a predominant role to the overall environmental impact (ranging from 58.9 % to 89.6 %). Under the assumption that Only- Product releases are examined (O.P. models) where energy and fuel consumption are not considered, Sea Transportation appeared as the principal contributor to human health and environmental impacts with adverse effects on Respiration of Organics. The highest contribution to the environmental impact however, appeared to be the GHG emissions caused by the fuel consumption of trucks during Road Transportation and Road Distribution. The results of this study are in good agreement with relevant research concerning impact of fuels to Climate Change when consumed in engines. Combustion engines were the reason why Respiration of Inorganics was presented in high levels, as well as for the noticeable levels of environmental impact categories indicators such as the Climate Change, the Acidification/Eutrophication and the Ecotoxicity. Sensitivity analysis showed that even under large variations in participation rates of LC stages, Sea and Road Transportation remain the main contributors to the overall impact of life cycles. The results of the present LCA case studies can be applied to a wide range of regional, national or even international areas with different geographical characteristics and product supply chains for the modes examined. The outcomes of the present study can support improvements in the relevant regulatory frameworks and can facilitate recommendations in guidelines, good industrial practices and procedures, in an effort to reduce the impact of fuel releases to vulnerable receptors. ACKNOWLEDGMENTS The present study was performed as part of the PROTEAS project [LIFE09 ENV/GR/000291] REACH Protocol for Emissions and Accidental Scenarios in Supply and Distribution of Fuels and Petrochemical products, which was 50% co-funded by the European Commission under the Environment Policy and Governance component of the LIFE + Programme. REFERENCES Breierova L, Choudhari M An Introduction to Sensitivity Analysis. Massachusetts Institute of Technology (MIT). CONCAWE Extraction, First treatment emission and loading of liquid & gaseous fossil fuels, Inventory Guidebook. E.U. CONCAWE Extraction, Gasoline distribution networks, Inventory Guidebook. E.U. CONCAWE Extraction, Gasoline distribution, Inventory Guidebook. E.U. CONCAWE. 2009, updated EMEP/EEA Emission Inventory Guidebook. E.U. Dr. C.A. Lewis Fuel and Energy Production Emission Factors. MEET Project: Methodologies for Estimating Air Pollutant Emissions from Transport. EPA Protocol for equipment leak emission estimates. USA.

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