Carbon Dioxide Emissions Reduction Estimates: Potential Use of Biofuels in Mauritian Transport Sector for Cars and Dual Cars

Abstract

One of the major areas of research in clean energy technology for transportation
sector is the use of biofuels, and the Government of Mauritius has adopted a
strategy of Building a Green future for Mauritius through the Maurice Ile Durable
(MID) concept through a shift to renewable sources of energy from imported fossil
fuels. The present study estimates the respective amounts of carbon dioxide
emitted from the transport sector in Mauritius. A predetermined portion of the
present engine fuel(s) being used have been replaced by a renewable biofuel (which
are gasoline−ethanol fuel blends E10, E15, E20 and E25) to estimate the reductions
in the carbon dioxide emissions. The specific objectives of the study were to
perform an inventory of the types of vehicles circulating on the roads of Mauritius,
estimate the types, and average and maximum quantities of motor fuel consumed,
substituting a fraction of the currently used petroleum fuels in cars and dual cars
with ethanol to determine CO₂ emissions reduction for 1998−2007, and thereafter
making emissions projections for 2008−2017 using a regression technique. Results
show that the CO₂ emission kept on increasing each year for Mauritius from the transportation sector. Out of the 1,249,170 tCO_2e emitted in 2007, the emissions of CO₂ from gasoline and diesel were 25 % and 39 %, respectively. 151,950 vehicles using gasoline were circulating on the road in 1998 and in 2007 the amount has increased to 222,344. The emission from cars and dual cars using gasoline was 79,305 tCO_2e in 1998 and in 2007 this had increased to 112,746 tCO_2e. From the fuel switch the estimated avoided gasoline from E10, E15, E20 and E25 for the year 1998 were 2,900, 4,069, 5,377 and 6,650 tones. These have increased to approximately 4,123, 5,865, 7,607 and 9,349 tones the different gasoline−ethanol blending in 2007. The avoided CO₂ emission from E10 was 9,216 tones CO₂ in 1998 and increased to 13,102 tons in 2007.Thus, the percentage reduction of CO₂emission using E10 was found to be 3.2% in 1998 and this increased to 4.1% reduction of CO₂ in 2007. Using E25, a drastic reduction of the emission in 1998 where approximately 21,131 tCO_2e was avoided using E25 and in 2007 the amount avoided was 29,709 tCO_2e. This represents a reduction in CO₂ emissions of 7.5% in 1998 compared to 9.4% in 2007 using E25. Projections were made for 2008−2017 and it was found that using E10 as a biofuel fuel in the transportation sector will save about 80,755 tones of gasoline and the resulting total avoided CO₂ emission for the year 2008−2017 will reduce to approximately 188,604 tCO_2e. E25 showed a more positive effect as the total avoided gasoline for the projected year 2008−2017 was found to be 184,943 tones and avoided CO₂ was 411,946 tCO_2e.

Keywords: Carbon dioxide; Transport; Biofuel; Gasoline−ethanol blends;

Emissions reductions.