Overview report on vehicle fuel consumption and CO 2 emissions

Transcription

1 Overview report on vehicle fuel consumption and CO 2 emissions Prepared by the International Council on Clean Transportation (ICCT) as part of the Cleaner Car Contracts initiative OVERVIEW REPORT March 216

2 Introduction Cleaner Car Contracts (CCC) is a collaboration of European fleet owning and leasing companies aiming to introduce more fuel-efficient cars into the European vehicle fleet. Together we improve employee mobility and reduce corporate emissions. The initiative was established in 21 by Natuur & Milieu. It now brings together many companies in The Netherlands and Belgium working on a more fuel-efficient car fleet and calling upon the EU to set ambitious CO 2 targets for cars also in real-world conditions. The ICCT is an independent nonprofit organization founded to provide firstrate, unbiased research and technical and scientific analysis to environmental regulators. Fuel consumption data from the Cleaner Car Contracts initiative was analyzed in the From Laboratory to Road study, which investigates the gap between on-road and official CO 2 emissions of European passenger cars. This report provides an overview of the fleets benchmarked in the Cleaner Car Contracts initiative. Since the official and on-road performance can differ dramatically, the benchmark uses both official and on-road fuel consumption figures. Benchmark The Cleaner Car Contracts benchmark study covered a large number of vehicles from diverse company fleets. Fifteen companies provided data for approximately 4, vehicles with model years ranging form 199 to 216. The data included valid official and on-road fuel consumption values for roughly 3, passenger cars and delivery vans. The fleets were investigated by segment, fuel type, and finally by carbon dioxide (CO 2 ) emissions. Figure 1 plots the share of different vehicle segments in the Cleaner Car Contracts fleets over model years. In total, the majority (6%) of vehicles were medium-sized passenger cars, followed by small cars (16%), vans (14%), and large cars (1%). The share of medium-sized cars is particularly high for more recent model years. Large variances were observed in vehicle sizes across

3 different fleets; for instance, some fleets primarily consisting of vans while others included no or few vans. 6% Fleet share 4% 2% % Small Medium Large Van Figure 1: Shares of vehicle segments by model year 1. Figure 2 shows the development of powertrain shares in the Cleaner Car Contracts fleets. In total, roughly two thirds of vehicles were diesel powered, while roughly one fourth were petrol powered. The share of plug-in hybrid electric vehicles increased significantly in newer model years, reaching approximately 2 percent in 216. In total, hybrid electric vehicles and plug-in hybrid electric vehicles accounted for three and four percent of the fleet respectively. Other powertrains, including battery electric vehicles as well as natural gas and liquefied petroleum gas powered vehicles, made up roughly one percent of the fleets. 1 Vehicle segments were defined as: small (A- and B-segment), medium (C- and D-segment), large (E-, F-, J-, and M- segment), and vans (delivery vans).

4 6% Fleet share 4% 2% % Diesel Petrol Hybrid Plug in hybrid Other Figure 2: Shares of fuel types by model year. The benchmark analysis investigates official and reported on-road CO 2 values. Since virtually all of the carbon in the fuel is converted to CO 2 during combustion, these values also reflect the vehicles fuel consumption 2. Figure 3 shows the development of official and real-world CO 2 emission values over vehicle model years. On paper, newer vehicles included in the Cleaner Car Contracts benchmark are more fuel-efficient than older ones: while average official CO 2 emissions of the entire fleet are 118 g/km, new vehicles (model year 216) have considerably lower official CO 2 values, on average 97 g/km. However, this downward trend in official values does not necessarily translate into on-road fuel savings due to the increasing gap between official and on-road performance. 2 The following factors were used to convert from fuel consumption to CO 2 emissions: 23.4 g CO 2/km per liter petrol/ km and 26.5 g CO 2/km per liter diesel/ km.

5 18 CO 2 emissions (g km) Official On road Figure 3: Development of official and on-road CO 2 emissions. Figure 4 displays the development of average official and on-road CO 2 emission values by powertrain. On-road CO 2 emissions were significantly higher than official values for all powertrains, and the gap between official and on-road values has been widening. The gap is particularly notable for plug-in hybrid electric vehicles. Figure 5 shows the development of average official and on-road CO 2 emission values by vehicle segment. Official CO 2 values decreased for newer model years in all vehicle segments, although on-road CO 2 did not decrease to the same extent. Excluding plug-in hybrid electric vehicles from the segment averages has a notable effect on official CO 2 values in the large segment.

6 CO 2 emissions (g km) Diesel Hybrid Petrol Plug in hybrid Official On road Figure 4: Development of official and on-road CO 2 emissions by powertrain. Small Medium CO 2 emissions (g km) Large Van Official On road All vehicles Excluding plug in hybrids Figure 5: Development of official and on-road CO 2 emissions by vehicle segment, including and excluding plug-in hybrid electric vehicles.

7 Figure 6 compares the gap observed in the entire CCC fleet with data from Travelcard, a popular fuel card 3. In total, the CCC fleet has a lower gap between on-road and official CO 2 emissions than was observed in Travelcard data. For both datasets, the gap is considerably higher including plug-in hybrid electric vehicles than excluding them, indicating that plug-in hybrid electric vehicles have a significantly higher gap than conventional powertrains. In total, the gap between on-road and official CO 2 values translates into additional annual fuel expenses of around 62 per vehicle or approximately 25 million for all fleets contributing data to the Cleaner Car Contract initiative 4. Gap between on road and official CO 2 emissions 6% 5% 4% 3% 2% 1% % CCC average Travelcard Excluding plug in hybrid electric vehicles All vehicles Figure 6: Gap between on-road and official CO 2 emission values compared to the Travelcard fleet, including and excluding plug-in hybrid electric vehicles. Figure 7 shows official and on-road CO 2 emission values by vehicle segment for all companies participating in the CCC initiative. The figure includes the Cleaner Car Contracts average and a best in class metric, which was defined as the most efficient company fleet in each vehicle segment. The figure shows that CO 2 emissions typically increase with vehicle size and that on-road CO 2 3 See the From Laboratory to Road study for details on the analysis of Travelcard data. 4 Simplified calculation using the median annual mileage for the CCC fleet and a fuel cost of 1.3/l.

8 emissions are consistently higher than official figures, on average by roughly 4 percent. The difference between the average and best in class official CO 2 values also increases with vehicle size, which is primarily due to the inclusion of plug-in hybrid electric vehicles, which have particularly low official CO 2 values and are most common in the medium and large segments. 25 CO 2 emissions (g km) Small Medium Large Van All Vehicle segment Official On road CCC best in class Figure 7: Average and best in class official and on-road CO 2 emissions by vehicle segment in the Cleaner Car Contracts fleets 5. On the whole, the benchmark of Cleaner Car Contracts data shows that the participating companies are investing in fuel-efficient vehicles, as indicated by decreasing official CO 2 values and the considerable share of hybrid and plugin hybrid electric vehicles. Nevertheless, these efficiency improvements on paper do not necessarily yield on-road fuel savings, in part due to the increasing gap between official and real-world fuel consumption values. The increasing gap primarily is a result of increasing exploitation of tolerances and flexibilities during vehicle testing 6. 5 The best in class values for the large segment include a high share (38%) of plug-in hybrid electric vehicles and are thus comparatively low. 6 See Tietge et al., From laboratory to road: A 215 update of official and real-world fuel consumption and CO 2 values for passenger cars in Europe, and Stewart et al., Impact of real-world driving on emissions from UK cars and vans,

9 Fleet managers can curb the growing gap between official and on-road fuel consumption values, for example by: selecting vehicle models and manufacturers that have a comparatively low gap (see the From Laboratory to Road study) encouraging drivers of plug-in hybrid electric vehicles to regularly charge the battery conducting trainings on eco-driving optimizing routes for fuel efficiency supporting policies for more rigorous vehicle testing