Based on the final NREL report, the DOE said "using coconut methyl ester (CME) or coco-biodiesel is just like using diesel fuel – only better."
The NREL report also stated that CME consistently yielded the same results as diesel fuel, but with more positive results.
The report was based on the analyses made on local CME, conventional diesel fuels and CME-diesel blends.
According to DOE, tests showed that both diesel and CME fuels met existing Philippine National Standards (PNS) for diesel fuel quality. CME, however, scored better in terms of cetane number, flash point, and sulfur content compared to diesel.
Citing the final report, the DOE said CME has a cetane number of 70, while diesel only has 56. The higher cetane number of CME means it burns more completely, resulting in more power, better engine performance, longer mileage and lower emission for vehicles.
"A higher flash point means CME is safer to handle and store than diesel, because it will take a higher temperature to ignite it. NREL results show that CME’s flash point is 107 degrees Celsius, compared to diesel fuel’s flash point of 79 degrees Celsius," the report said.
The final result of the tests also showed that in terms of sulfur content, CME is nearly sulfur-free, unlike diesel fuel. "Sulfur content in fuel releases sulfur dioxide, a known air pollutant that can cause a number of respiratory illnesses such as breathing difficulties, as well as aggravate existing heart disease. Sulfur dioxide also poses environmental problems such as haze and acid rain," it said.
The NREL tests also showed that CME-blended diesel does not take up significant amounts of water, which means the local oil companies’ practice of pushing diesel fuels through the pipeline with the use of sea water will have no significant effect on the quality of the CME-diesel blend.
Under different storage conditions, CME and CME-blended diesel showed similar levels of stability as diesel, meaning they will not clog fuel filters and injectors and are just as safe for the engine as diesel. Tests also showed that both diesel and CME-diesel blends had comparable results in terms of their corrosive effects on the engine’s metal, proving that one fuel type is not better than the other.
The DOE is the lead agency promoting the government’s biodiesel program, which aims to mandate the use of CME-based biodiesel blends as motor fuel. Currently, the DOE is working closely with Congress for the passage of the Bio-Fuels Bill, which seeks to mandate the use of biodiesel and bioethanol as fuel additives to diesel and gasoline, respectively.
Oil companies and car manufacturers have been raising technical concerns regarding the mandatory blending of CME into diesel fuel, including such issues as engine compatibility and the effects of CME on the storage, handling and distribution systems and facilities of the oil companies. However, in a recent forum entitled "Are we ready for clean fuels?", the Chamber of Automotive Manufacturers of the Philippines, Inc. (CAMPI) said that a one percent blend is acceptable, as long as it conforms to Philippine National Standards.