Drive-style emissions testing on the latest two Honda hybrid technologies

Abstract

Introduction Hybrid technology is seen by many as a potential solution to reduce vehicle emissions in cities. However type approval tests of hybrid vehicles measure emission levels comparable to those of conventional cars in the same market segment. It has been argued that type approval tests do not represent the reality of emission in cities therefore, to quantify the real emission of hybrids and to compare them with those of conventional vehicles in the same conditions, an emission measurement campaign was organised. Acquisition campaign Three Honda cars, one conventional (the Civic 2.0) and two hybrids (the Civic IMA and the Civic Hybrid), equipped to collect emissions as well as the engine and vehicle working parameters were driven three times by twenty drivers on the same urban route. Drivers were asked to drive normally and not requested to do anything special but to scrupulously follow the given itinerary. Results Two main results were obtained: average and maximum emission levels for the three cars are quantified; the effects of the drivers on such levels assessed. The conventional car (with two people and 250 kg of measurement tools onboard) consumes an average of 12.6 l/100 km, its CO2 emissions range between 200 g/km and 300 g/km with an average of 260 g/km. CO emissions range between 0.25 g/km and 6.25 g/km (Euro IV limit is 1 g/km) with an average of 2 g/km. The most recent of the two tested hybrids consume in average 8.23 l/100 km and emits between 150 and 230 g/km of CO2 with an average of about 180 g/km; it emits virtually no CO in the majority of cases but can reach up to 1.8 g/km and average CO emissions are about 0.2 g/km. The hybrid performs always better than the conventional; in terms of CO2 and consumption it can have up to a 30% reduction and in terms of CO up to 90% reduction. Conclusions The wideness of the measured ranges depends mostly on the drivers. Women tend to consume and emit less than men. The reason for this is the different way they use the accelerator pedal; they push it less and keep it steadier. In other word the standard deviation of the accelerator position (or throttle) is lower. It is here shown how a correlation exist between the throttle standard deviation and the emissions which justify using such parameter as the indicator of drive-style.

Smartphones as an integrated platform for monitoring driver behaviour: The role of sensor fusion and connectivity

“…Two main aspects of tactical behaviour were reviewed: driver aggressiveness and eco-friendliness. Studies showed that aggressiveness and ecofriendliness are interrelated, though not identical (Alessandrini et al, 2009;Sivak, M. & Schoettle, 2012). Some smartphone applications were developed for improving tactical driving behaviour 8,9 .…”

Development of driving cycles for electric vehicles in the context of the city of Florence

“…However, logging of powertrain values can also be needed (e.g. rpm, speed, throttle position, engine parameters if ICE, battery/inverter/powertrain parameters if EV or HEV) especially in the case that the aim is to correlate emissions (directly measured at tailpipe) and driving style (Alessandrini et al, 2009) or to correlate traction power to probability of occurrence (Shankar et al, 2012). The availability of logging capabilities through cheap and wide diffusion devices such as car infotainment system and smartphones highlights new possibilities for the monitoring of driving attitudes (Gerardo and Lee, 2009); such data can be used for driver training through continuous learning (Beusen et al, 2009;Corcoba Magana and M unoz-Organero, 2011;Manzoni et al, 2010), thus promoting safe or fuel-saving driving styles.…”

Hybrid-Electric Passenger Car Carbon Dioxide and Fuel Consumption Benefits Based on Real-World Driving

“…The relationships between fuel use, emissions and VSP are reflected in the latest EPA regulatory model for mobile source emissions, MOVES, which uses VSP and vehicle speed to forecast emissions from the on-road vehicle fleet. 10 Laboratory measurements of fuel consumption from various model HEVs have shown a dependency on HEV technology, 40 drive cycle 11,41 and ambient temperature. 11,14,42,43 For example, HEVs showed up to three times higher fuel consumption for aggressive, stop-and-go drive cycles compared to highway driving.…”

“…44 Thus, HEVs offer up to two times the fuel consumption improvement compared to gasoline CVs, and HEV fuel consumption varies with operating mode. Four prior studies (See Supporting Information (SI) Table S-1) compared the performance of CV to HEV, 11,14,40,44 but each of these studies had shortcomings that do not enable quantification of HEV benefits that can be used for modeling any type of real-world driving. These shortcomings included: (i) the compared CV was of different make/model/model year or aerodynamics; 11,44 (ii) compared CV was manual transmission 40 and thus too dependent on driver behavior; and (iii) comparative analysis was only conducted at the trip or full drive-cycle level and therefore not amenable to quantifying HEV benefit as a function of operating modes such as those based on VSP.…”

“…Laboratory measurements of fuel consumption from various model HEVs have shown a dependency on HEV technology, drive cycle , and ambient temperature. ,,, For example, HEVs showed up to three times higher fuel consumption for aggressive, stop-and-go drive cycles compared to highway driving . Federal Test Procedure (FTP) fuel consumption rate comparisons for 7 MY 2000 vehicles showed the Toyota Prius rate (3.97 L/100km) was about half that of the 3 tested gasoline direct-injection vehicles (7.62, 8.53, and 10.4 L/100km) and comparable to that for 3 diesel direct-injection vehicles (3.38, 4.08, and 5.32 L/100km) .…”