Review of in use factors affecting the fuel consumption and CO2 emissions of passenger cars

This report primarily investigates the factors that affect fuel consumption and CO2 emissions which are not accounted for in the current type approval test and result in a shortfall between type approval and real-world fuel consumption or the corresponding CO2 emission values. A comprehensive literature review is carried out, in which we examine the available information and aim to provide qualitative and quantitative data. Where information is e insufficient, we point out the gap in knowledge. In addition, we have examined by means of simulation the significance of several factors that may change during every-day operation and may depend either on the driver or on external conditions. Several factors were identified affecting the in-use fuel consumption and CO2 emissions resulting in a shortfall between the type approval and real-world values. These include the increased electrical power load (e.g. A/C, steering assist), aerodynamic alterations (roof box, aerofoils), ambient conditions (temperature, wind, rain and altitude), driving behavior (aggressive driving, driver training), vehicle condition (lubrication, tyre condition), increased vehicle mass (passengers, additional equipment), road conditions (road surface, traffic conditions). They are complemented by so-called "flexibilities" associated with the existing NEDC-based type approval procedure. The combined effect of the different factors affecting CO2 emissions,, although not fully cumulative, can result in shortfall values ranging between 25% and 35%, based on information collected, the calculations run and the assumptions adopted in this study. These figures are in line with other literature sources where shortfall ranges from 20% up to 50% compared to the official certification value are reported. The per-passenger CO2 performance significantly improves when the occupancy rate is considered, hence a separate analysis was performed to this end. It can be concluded that due to the increase complexity of modern vehicles, the increasing number of passenger comfort systems and the great variety of possible operating conditions, it is difficult to capture the real-world fuel consumption with an exhaustive accuracy. It is expected that the introduction of the new test protocol (WLTP) will be a step forward in closing this shortfall. A separate analysis on the expected WLTP impact on CO2 is presented. It cannot be overlooked that driver behavior is an important element and therefore additional measures, in particular proper driver training and information, can help to reduce the discrepancy observed by drivers between their own in-use CO2 emissions from passenger cars compared to the test results.JRC.C.4-Sustainable Transpor

fUel-SAVing trip plannEr (U-SAVE): a product of the JRC PoC Instrument: Final report

Available tools for trip planning mostly rely on travel time and travel distance. Fuel costs, when taken into account, are based on simplified fuel consumption models and are usually independent from vehicle type and technology. Building on the work carried out by the Sustainable Transport Unit of the Joint Research Centre, European Commission, in developing (a.) CO2MPAS, the official tool supporting the WLTP/NEDC Correlation Exercise and allowing the back-translation of a WLTP test to the equivalent NEDC CO2 emission value during the type approval, and (b.) Green Driving, an interactive web-based tool allowing the estimation of fuel costs and CO2 emissions of individual car journeys on the basis of variables such as car segment, engine power, fuel type and driving style, the present project aimed at developing and proving the concept of a routing machine to be used when fuel consumption minimization is considered. Throughout the project a stand-alone off-board trip planner has been developed, the U-SAVE Desktop Version, while a smartphone application, the U-SAVE Navigation Application, is currently under the last development phase, and shall be used once completed as a low cost in-board navigation system. The tool has been extensively validated internally demonstrating both its capability to accurately estimate fuel and energy consumption via alternative trip options, and its capacity to provide a more efficient route when different from the shortest and/or fastest options. An open-access version of the tool is expected to become a reference instrument for private citizens who are concerned about their fuel consumption and a more efficient use of their vehicles, while a premium API-based commercial version of the tool can operate as a viable and scalable business model targeting, among others, established navigation software providers who want to extend their offering by providing an alternative route option to their clients, mainly private companies managing fleets of light-duty vehicles, for whom saving fuel from the daily vehicle operations is of crucial financial importance.JRC.C.4-Sustainable Transpor

From NEDC to WLTP: effect on the type-approval CO2 emissions of light-duty vehicles

The present report summarises the work carried out by the European Commission's Joint Research Centre to estimate the impact of the introduction of the new type approval procedure, the Worldwide Light duty vehicle Test Procedure (WLTP), on the European car fleet CO2 emissions. To this aim, a new method for the calculation of the European light duty vehicle fleet CO2 emissions, combining simulation at individual vehicle level with fleet composition data is adopted. The method builds on the work carried out in the development of CO2MPAS, the tool developed by the Joint Research Centre to allow the implementation of European Regulations 1152 and 1153/2017 (which set the conditions to amend the European CO2 targets for passenger cars and light commercial vehicles due to the introduction of the WLTP in the European vehicle type-approval process). Results show an average WLTP to NEDC CO2 emissions ratio in the range 1.1-1.4 depending on the powertrain and on the NEDC CO2 emissions. In particular the ratio tends to be higher for vehicles with lower NEDC CO2 emissions in all powertrains, the only exception being with the plug-in hybrid electric vehicles (PHEVs). In this case, indeed, the WLTP to NEDC CO2 emissions ratio quickly decreases to values that can be also lower than 1 as the electric range of the vehicle increases.JRC.C.4-Sustainable Transpor

Feasibility study and prototyping of a blockchain-based transport-service pricing and allocation platform

This report summarizes the activity and findings of the JRC Proof of Concept Project Ridechain. The project investigated the applicability and market potential of blockchain technology for asset sharing in the road transport sector. The project comprised two principal activities. The first activity was market research and analysis to support the development of a new service concept and business model for blockchain-powered shared mobility. Specifically, the research resulted in the definition of a novel technology platform that leverages blockchain, cloud services, and in-car technology to enhance trust, streamline coordination and improve information exchange in P2P car sharing ecosystems. The second activity was technology prototyping to demonstrate the technical feasibility of the novel service concept using state of the art blockchain and IoT frameworks. These two activities provided answers to two respective research questions. First, what would be a high-value transport sector market to which a blockchain-powered technology product could offer a high-value solution? Second, how could this technology product be realized?JRC.C.4-Sustainable Transpor

Ανάπτυξη ενός εργαλείου ποσοτικοποίησης των εκπομπών CO2 από την οδική κυκλοφορία με σύνδεση λεπτομερούς προσομοίωσης οχήματος και μακροεργαλείων εκπομπών

CO2 emissions from road transport have an increasing importance on the discussion about climate change. Today several models exist potentially capable of evaluating the effect of technology and policy on the energy performance of a transportation system, though they either lack the accuracy required, or they require a level of detail on their inputs, which is prohibiting for large-scale simulations and/or integration with other models or software, e.g. traffic simulation models, cost calculation components, etc. In this light, the objective of the present thesis is the combination of standard vehicle emission simulation approaches, used in vehicle simulation models, with limited statistical/empirical relationships provided by measurement data, and advanced data analysis and machine learning technics, to provide a robust and reliable, yet flexible and quick, integrated framework for analyzing and evaluating the influence of technology and policy on passenger cars’ fuel consumption and CO2 emissions. The integrated simulation-based framework is used mainly to support and assess the effects of the transition from the, up-to-recently used, NEDC-based type approval process, to the newly-defined WLTP, which has taken effect in September 2017. Moreover, the tool is used to evaluate the effect of the newly introduced amendments in the type-approval legislation concerning hybrids and other low emission vehicle segments, and, lastly, to replicate real driving emissions gathered through a Portable Emissions Measurement Systems (PEMS) tests campaign.Οι εκπομπές CO2 από την οδική κυκλοφορία έχουν ολοένα μεγαλύτερη σημασία στη συζήτηση για την κλιματική αλλαγή. Διάφορα μοντέλα και πρακτικές εφαρμόζονται σήμερα για την εκτίμηση της επίδρασης τεχνολογικών και πολιτικών επιλογών στην κατανάλωση καυσίμου επιβατικών οχημάτων και στην ενεργειακή αξιολόγηση συστημάτων μεταφοράς, ωστόσο, αυτά, είτε δεν διαθέτουν την απαιτούμενη ακρίβεια στο τελικό αποτέλεσμα, είτε χρειάζονται ένα επίπεδο λεπτομέρειας στις παραμέτρους εισόδου που απαγορεύει τις προσομοιώσεις σε μεγάλη κλίμακα ή/και τον συνδυασμό με άλλα μοντέλα ή λογισμικά, όπως μοντέλα προσομοίωσης κυκλοφορίας, μοντέλα υπολογισμού κόστους κ.α.. Υπό αυτό το πρίσμα, η παρούσα διδακτορική διατριβή στοχεύει στο συνδυασμό προσεγγίσεων προσομοίωσης κατανάλωσης καυσίμου οχημάτων, όπως αυτά χρησιμοποιούνται σε αναλυτικά μοντέλα προσομοίωσης, με εμπειρικές σχέσεις που προκύπτουν από τον συνδυασμό και την ανάλυση δεδομένων μετρήσεων και άλλων διαθέσιμων δεδομένων, σε ένα ολοκληρωμένο, ευέλικτο και ακριβές εργαλείο, το οποίο επιτρέπει την αξιολόγηση της επίπτωσης σύγχρονων τεχνολογιών και πολιτικών επιλογών στην κατανάλωση καυσίμου επιβατικών οχημάτων. Το συγκεκριμένο εργαλείο χρησιμοποιείται κυρίως για την υποστήριξη και την εκτίμηση της επίπτωσης της μετάβασης από το μέχρι πρότινος ισχύον πρωτόκολλο μέτρησης το οποίο εφαρμόζεται στην έγκριση τύπου κατανάλωσης καυσίμου και εκπομπών CO2 επιβατικών οχημάτων στην Ευρώπη, το NEDC, στο νέο, το οποίο αναπτύχθηκε από τα Ηνωμένα Έθνη και ξεκίνησε να εφαρμόζεται στην ευρωπαϊκή νομοθεσία από το Σεπτέμβριο του 2017, το WLTP. Επιπλέον, το εργαλείο εφαρμόζεται για την εκτίμηση της επίπτωσης των αλλαγών της σχετικής νομοθεσίας οι οποίες αφορούν οχήματα χαμηλών εκπομπών (ηλεκτρικά, κ.α.), και, τέλος, για την αναπαραγωγή δεδομένων εκπομπών υπό πραγματικές συνθήκες οδήγησης, τα οποία συλλέχθησαν μέσω φορητών συστημάτων μέτρησης εκπομπών (PEMS)

A simulation-based methodology for quantifying European passenger car fleet CO2 emissions

Common approaches to assess the evolution of CO2 emissions from road vehicles are usually based on (a) estimates of future fleet composition, where most approaches consider vehicles at a rather aggregated level, and (b) emission factors, which are either based on CO2 certification data or statistically-provided functional relationships obtained from real world test data, or a combination of the two. This approach has certain limitations in capturing the effect of new technologies on CO2 emission related policy initiatives. The present study proposes a new method for the detailed calculation of the European light duty vehicle fleet CO2 emissions, which could help to overcome such limitations, achieve better results when making CO2 emissions projections and better support future policies. Simulation at individual vehicle level is combined with fleet composition data, retrieved from the official European CO2 emissions monitoring database, and publicly available data regarding individual vehicle characteristics in order to calculate vehicle CO2 emissions and fuel consumption over different conditions and vehicle configurations. The methodology is applied to analyse and assess the impact of the introduction of the new certification procedure, the Worldwide Light duty vehicle Test Procedure (WLTP), on the European car fleet CO2 emissions. Results show an average WLTP to NEDC CO2 emissions ratio of approximately 1.2. The increases in CO2 emissions are higher for cars exhibiting lower NEDC emission values (additional 29 and 25 gCO2/km for vehicles emitting 100 and 119 gCO2/km, respectively). At higher emission levels (about 250 CO2 g/km) WLTP and NEDC present comparable results. Three possible scenarios for the translation of projected NEDC CO2 emissions to WLTP-based ones are quantified.JRC.C.4 - Sustainable Transpor

Analysing the real-world fuel and energy consumption of conventional and electric cars in Europe

The transport sector constitutes one of the main sources of greenhouse gas emissions in the European Union. Although the literature is rich in studies assessing the factors influencing energy consumption in real world driving, few analyse the divergence between certified and real-world consumption on a fleet level and annual temporal resolution. The present work builds on the findings of previous studies to provide a complete simulation-based approach for fleet-level projections in real-world scenarios. A tailored simulation framework for fleet-wide analysis has been updated and validated extensively for current vehicle configurations. In addition to modelling, the analysis used data describing real-world conditions and vehicle characteristics representative of the European passenger car fleet and operation profile. Validation demonstrates good accuracy in simulating the vehicle measured consumption values with a near-zero mean error when simulating laboratory and on-road measurements. The impact of the certification procedure was quantified at 6% for both the combustion engine and battery electric vehicles. The influence of real-world factors such as traffic, ambient temperature and cabin air conditioning was quantified, and the results show a greater energy impact in the cold than in warm conditions.JRC.C.4 - Sustainable Transpor

Development of a Low-Cost Measurement System for Soil Electrical Conductivity and Water Content

Soil electrical conductivity (EC) and water content are key indicators of soil health, influencing nutrient availability, salinity stress, and crop productivity. Monitoring these parameters is critical for precision agriculture. However, most existing measurement systems are costly, which restricts their use in practical field conditions. The aim of this study was to develop and validate a low-cost, portable system for simultaneous measurement of soil EC, water content, and temperature, while maintaining accuracy comparable to laboratory-grade instruments. The system was designed with four electrodes arranged in two pairs and employed an AC bipolar pulse method with a constant-current circuit, precision rectifier, and peak detector to minimize electrode polarization. Experiments were carried out in sandy loam soil at water contents of 13%, 18%, and 22% and KNO3 concentrations of 0, 0.1, 0.2, and 0.4 M. Measurements from the developed system were benchmarked against a professional impedance analyzer (E4990A). The findings demonstrated that EC increased with both frequency and water content. At 100 Hz, the mean error compared with the analyzer was 8.95%, rising slightly to 9.98% at 10 kHz. A strong linear relationship was observed between EC and KNO3 concentration at 100 Hz (R2 = 0.9898), and for the same salt concentration (0.1 M KNO3) at 100 Hz, EC increased from ~0.26 mS/cm at 13% water content to ~0.43 mS/cm at 22%. In conclusion, the developed system consistently achieved <10% error while maintaining a cost of ~€55, significantly lower than commercial devices. These results confirm its potential as an affordable and reliable tool for soil salinity and water content monitoring in precision agriculture