Urban taxis and air pollution: a case study in Harbin, China

Exploring Urban Taxi Drivers’ Activity Distribution Based on GPS Data

“…The results are shown in Table 2; we can see that the lowest taxi service frequency is less than 0.4 per hour, and the highest is almost 2.7 per hour. The average number of each taxi operating per day is between 39 and 44 times, which is higher than other cities statistics, such as in Harbin where there are 32 taxi service times for each taxi operating per day in 2008 [3], as well as 31 to 33 taxi service times per day in Beijing in 2007 [34]. During 2006 to 2007, Chen [5] also calculated the average operation time for each taxi per day, which is between 35 and 40 times per taxi per day, which is also lower than that in 2011.…”

“…Due to the 24 hours operation per day, taxis account for a higher proportion in the urban traffic volume and air emission pollution [3]; more researchers attempt to analyze taxi operation status and taxi driver's routing choice based on the GPS traces data, aiming to reduce taxi driver's vacant travel distance and cruising time, and also this can save energy resource. In the taxi operation status analysis aspect, researchers analyze the taxi daily average operation distance, taxi passenger demand distribution, daily average operation frequency, and different driver's operation patterns; the reader can be referred to Hu and Feng [4], Chen [5], Jiang et al [6], Wen et al [7], Liu et al [8], Hu et al [9], and Zhang and He [10].…”

Taxi Downsizing: A New Approach to Efficiency and Sustainability in the Taxi Industry

“…As shown in Figure 4, we calculated the average daily mileage of taxis, i.e., 336 km, in Hangzhou, which was close to 320.1 km in Harbin [3], 300 km in Shanghai [36], and 360 km in Beijing [4]. For measuring the emission due to the daily vehicle kilometer travel (VKT), we chose three emissions (i.e., CO, NOx, and HC) because they are the primary pollutants from gasoline vehicles, as presented by Gwilliam et al [60].…”

“…He et al [59] illustrated that the average fuel efficiency was 11.03 km/L, based on the data of all passenger cars in China. An et al [3] showed that the fuel efficiency of taxis in Harbin was between 10.5 km/L and 11.6 km/L. Then, a reasonable assumption of the fuel efficiency for standard-car taxis in Hangzhou could be 11 km/L or 9 L/100 km.…”

“…Even in the case that some passengers carry baggage, the vehicle roof could be armed with a trunk to hold the baggage. Various studies in China have shown that the average taxi speed is usually around 30 km/h in populated urban areas [3][4][5]. According to the vehicle's speed versus drag force graph in the Automotive Aerodynamics Handbook [6], which shows that the impact of aerodynamic drag force under low speeds (below 25 km/h) is small, the use of a trunk on the vehicle roof does not have severe negative impacts on the aerodynamic drag force.…”