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This study presents an experimental comparison of on-road fuel economy estimates of driving cycles generated by a locally-developed road load energy (RLE)-based method developed by Gerald Jo Denoga and the micro-trip approach. A Philippine public utility jeepney (PUJ) plying a selected local franchised route was fitted with on-board instrumentation to gather on-road speed-time data and fuel economy measurements for a total of 18 round-trips. These speed-time data were processed using computer codes written for both methods of generating drive cycles for chassis dynamometer testing. Candidate drive cycles developed by the RLE-based method were selected based on the calculated energy errors and residue errors of developed drive cycles. The candidate drive cycles developed by the micro trip method were selected by the absolute value difference of probability distribution of normalized frequencies.

The urban drive cycles for five different light duty vehicles (LDV) are developed in this study. The study presents the methodology in the development of the drive cycles in which the speed profile of the specific type of vehicle is surveyed with an on-board instrument. The speed data is processed using a program to execute the methodology in generating candidate drive cycles. The selected drive cycles are then used in the chassis dynamometer laboratory to estimate the fuel economies of each type of light duty vehicle considered. The developed drive cycles for the different types of light duty vehicles, namely (1) private cars, (2) taxis, (3) public utility jeepneys, (4) UV express, and (5) light duty trucks have average speeds of 17.97 kph, 13.57 kph, 10.87 kph, 14.69 kph and 8.43 kph respectively. The measured fuel economies for all the light duty vehicles tested ranges from 3 to 12 km/liter.

This paper presents the results of a two-phase Philippine study to determine the actual mileage (km/liter) of in-use diesel and LPG (liquefied petroleum gas or Auto-LPG) public utility jeepneys plying two separate Metro Manila urban routes using both on-road and chassis dynamometer tests. Measured average load factor in on-road tests was 60-70%. Dynamometer tests at 100% load factor utilized drive cycles derived from on-road speed data. A “diesel equivalent mileage” of actual LPG mileage, deemed indicative of LPG “fuel energy conversion efficiency” relative to diesel, was calculated (based solely on fuel heating values and densities) for comparing actual mileage from both fuels. The LPG actual mileage in both on-road and laboratory tests was lower than diesel mileage. In on-road tests, the LPG actual mileage was lower than diesel actual mileage by about the same percentage LPG heating value was lower than diesel’s per liter of fuel.

The instantaneous fuel consumption measurements obtained from the chassis dynamometer tests using the drive cycles for light duty vehicles in Metro Manila was used in the development of speed-acceleration-fuel consumption models. The Shepard’s interpolation method was used in the development of the models. A program C# language was used to execute the interpolation method.The resulting models are represented by speed-acceleration-fuel consumption surface graphs. The surface graph of each test vehicle represents its estimated fuel consumption variation according to its combined instantaneous speed and acceleration. Actual instantaneous speeds from speed data of surveyed vehicles, defining different traffic conditions by average speed, are used to interpolate instantaneous fuel consumption. Fuel economy, in terms of distance travelled (km) per volume of fuel consumed (liter), is computed from the totaled fuel consumption and total distance traversed.

The Philippine Biofuels Act of 2006 (RA 9367) requires commercial diesel fuel to be mixed with Coconut Methyl Ester (CME) in accordance with the Philippine Clean Air Act of 1999 (RA 8749). As of 2015, the blend percentage is at 2% CME v/v, contrary to the scheduled 5% as stipulated in the biofuels act. Researches done locally showing the performance and emissions of CME-fueled engines are few and thus the basis for the CME percentage increase is still questionable and hampers the drive for the further implementation of the policy. The study investigates the influence of varying percentages of CME blends (2%, 5%, 10%, 15%, 20% v/v) to the performance and emissions of a heavy-duty turbocharged common rail direct injection (CRDI) engine. The engine is run at steady state at partial load (50Nm and 250 Nm) and at near full load (500Nm). Each run is set at three pedal positions, α (25%, 50% and 60%), controlled directly from the engine control unit.

This paper presents a preliminary study to estimate, using on-road and laboratory tests, the mileage range of liquefied petroleum gas (LPG) as an alternative fuel for diesel-fed public utility jeepneys in the Philippines. Data from the study would be used by the Philippine Department of Energy to formulate and implement alternative fuel programs for public transport. On-road fuel consumption, load factor, and GPS speed data from selected in-use LPG and diesel jeepneys plying a chosen urban route were gathered to develop corresponding drive cycles for chassis dynamometer testing at 100% load factor were conducted to estimate an upper limit for fuel consumption. Measured on-road diesel jeepney mileage was about 6.7 km/liter at 63.5% load factor while that for LPG jeepney was 3.8-4.2 km/liter at 59.8% load factor. Drive cycle tests yielded 5.2 km/liter for diesel and 2.6-3.1 km/liter for LPG.