Nipa alcohol (Nipahol) may just be energy of the future.
“To drive cars and not just to gas up cooking stoves,” said Dr. Fiorello Abenes, a Department of Science and Technology Balik Scientist working on alternative energy at the Mariano Marcos State University (MMSU) campus in Batac, Ilocos Norte.
Abenes wants the Nipahol or nipa alcohol that he and fellow MMSU researchers have been working on to be used in gasoline-alcohol blends.
Since 2010, they have been studying hydrous ethanol containing 5 percent water in gasoline blends as high as 20 percent ethanol.
“We called it HBE-20, a blend of hydrous ethanol and E-10. We have tons of data to prove that HBE-20 is just as good, if not better than E-10.”
MMSU’s National BioEnergy Research and Innovation Center is willing to test the formulation side by side with the current E-10 mix, said Abenes.
Ethanol provides oxygen, making gasoline burn more cleanly in engines. The biofuel E10 is so named because it contains 10 percent ethanol and 90 percent gasoline. Because its use as a part of the fuel mix is mandated by the Biofuels Act of 2006, E10 is the most common biofuel used in the Philippines where it is widely accepted and available at all gas stations.
Nipahol is 95 percent ethanol with 5 percent water that is reflux distilled from the sap of the nipa palm. Reflux is a distillation technique involving the condensation of the distilled vapors and the return of a portion of the condensate to the distillation system from which it came from.
“It is the highest concentration of ethanol that can be obtained by distillation,” Abenes said.
Nipahol can be used to formulate E15, a blend of 15 percent ethanol and 85 percent gasoline. With 5 percent more ethanol than E10, E15 is typically 88 octane, higher than that in E10 which has an octane rating of 87.
“E15 with its 15 percent ethanol will be cheaper per liter than E10,” said Abenes, pointing out “it’s a discount that’s especially appealing in these times of sky-high fuel prices.”
Hydrous E-15 will be even cheaper, he said, having estimated the cost of production per liter of hydrous Nipahol to be P35.
Abenes said economists have estimated the cost of production per liter of hydrous Nipahol at P35. “The cost of removing the last 5 percent water can add 25 percent to the cost of producing fuel grade ethanol,” he added.
Based on prevailing prices in mid-2022, domestic fuel ethanol was priced at P69.79 per liter while imported fuel ethanol cost P48.66 per liter.
“Since we do not yet have a fully integrated Nipahol production system, nor the benefits of mass production and economies of scale, the cost of production of Nipahol is higher at P35 per liter,” explained Abenes.
The Implementing Rules and Regulations of the Biofuels Act require locally produced ethanol to be purchased before imported ethanol can be brought to the country. On average, local producers can supply only 50 percent of the bioethanol requirement for gasoline blending. The remaining 50 percent, roughly 300 million liters, comes from imported fuel ethanol, primarily from the US.
However, because the Philippine National Standard for fuel ethanol is pegged at 96.9 percent purity, “hydrous Nipahol falls a bit short of the standard by 1.9 percentage points,” Abenes said.
“That could be remedied by blending hydrous Nipahol with absolute, 100 percent ethanol at the rate of 2:1 which can then be used to formulate E-15. The resulting ethanol concentration of the mixture will be 96.7 percent,” Abenes added.
Nipahol comes from nipa palms that produce large quantities of a sugar-rich sap that can be used for ethanol production.
Nipa palm has been reported to have ethanol yields ranging from 6,480 liters per hectare to 20,000 l/ha, which makes it several times more productive than sugarcane.
Nipa palms grow along coastlines and is adapted to mangrove ecosystems. The Philippines, having the fifth longest coastline in the world, is said to have the third largest hectarage of nipa forests, estimated at 38,000 hectares. It is surpassed only by Indonesia and Papua New Guinea.
MMSU economists estimate that nipa forests can supply all of the 300 million liters of ethanol currently imported by the Philippines.
“For the P3 billion to P5 billion cost of building one industrial distillery, we can deploy thousands of our village-scale Nipahol distilleries and create income opportunities to coastal area residents,” Abenes said.
