Fuel System and Fuel Measurement - Decreasing Fuel Consumption and Exhaust Gas Emissions in Transportation - page 61

by 93/116/EC and ECE-R101 [ 7 , 8 ]. Fuel consumption is determined by a cycle
simulating urban driving as described in 70/220/EEC, Annex II in:
• Constant speed test at 90 km h -1 ; and
• Constant speed test at 120 km h -1 [ 9 ].
The results of the test are expressed in l (100 km) -1 . The fuel must be supplied
to the engine through a device capable of measuring the quantity consumed to
within ±2%. This device should not interfere with normal supply. There must be a
valve to permit rapid changeover from the general fuel supply system to the
measurement system.

4.1.1.1 Car and Light Duty Vehicle Technology

93/116/EC applies to the carbon dioxide emission and the fuel consumption of all
motor vehicles of the category M1. The weight of fuel consumed is calculated
according to the carbon balance method using the measured emissions of CO 2 and
other carbon-related emissions (CO and HC):

M gasoline ¼ fCO 2 ; CO ; HC ð Þ ð 4 : 1 Þ

The CO 2 emissions are measured during the test cycle simulating both urban and
highway driving patterns as described in 91/441/EEC (1), Appendix 1 of Annex
III. Test results are averaged and expressed in Europe in g km -1 or g mi -1 [ 10 ].
Similar to the EU method, in the USA the measured fuel is based on the
regulation 40 CFR Part 600-113 [ 11 ]. Fuel consumption is determined on test
benches according to the carbon balance method from the CO 2 , CO, and HC
emissions analyzed in miles gal -1 (US) in US EPA II and in Highway Fuel
Economy Cycle (HWFET) [ 12 , 13 ]. In Europe, the fuel consumption is expressed
in l km -1 or l (100 km) -1 , in the USA in gal mi -1 or in the most cases, in mpg.
Japan uses synthetic cycles, such as the 11 Mode cold and 10 ? 15 Mode hot
cycle, respectively, New Driving Cycle JC 08, which is similar to the NEDC;
however, they apply different speeds and gears [ 14 ].
The relation between the fuel consumption and the speed of an average mid-
sized car in the NEDC is presented in Fig. 4.3 [ 15 ].
According to the statistics, the average fuel consumption of a European mid-class
car is 6.2 l (100 km) -1 , i.e., 47.6 mpg (US) and 45.5 mpg (UK). The cold start phase
in the first 120-180 s demands an extraordinary large amount of fuel, above 30 l
(100 km) -1 i.e., 105 mpg (US) and 126 mpg (UK). The urban fuel consumption in the
second phase is 8.2 l (100 km) -1 , i.e., 28.7 mpg (US) and 34.4 mpg (UK) and the
highway fuel consumption in the last phase is 5.1 l (100 km) -1 , i.e., 46.1 mpg (US)
and 55.3 mpg (UK).