Biomass is an important source of energy for the rising energy demand in the Philippines, however it is still a huge untapped resource considering that the Philippines, being an agricultural country generates a huge amount of agricultural by-products and residues. In order to simultaneously reduce the amount of agricultural wastes and improve the quality of indigenous coal reserves in the country to support increasing electricity demand, the present study blends Semirara coal, a sub-bituminuous type of coal with torrefied coconut (Cocos nucifera) husk for establishment of recommended blending ratios. Proximate analysis, ultimate analysis, and calorific value were determined to characterize and understand the physical conditions and coal properties during combustion. Test results showed that blending Semirara coal with torrefied coconut (C. nucifera) husk by not less than 50% by weight would generally improve its quality in terms of its combustion properties thereby making these combinations of coal and biomass advantageous.

Utilizing and improving the quality of Philippine indigenous coal is getting more important in order to sustain the country’s high dependence on coal over the next 10 years and to keep up with the country’s growing energy demands. Also, environmental problems and negative impacts of agricultural wastes are drawing more and more attention since the quantity of agricultural wastes has been rising rapidly all over the world. In the Philippines, sugarcane (Saccharum officinarum) bagasse has been identified as one of the significant contributor to the country’s biomass energy resource. Hence, in this study, coal blending technique has adopted as a proper approach to improve the quality of indigenous coal reserves while concurrently reducing and reusing agricultural wastes. This paper aimed to establish recommended blending ratios for Semirara coal, a sub-bituminous type of coal from Semirara Island in the province of Antique, Philippines and sugarcane (S. officinarum) bagasse. Proximate analysis, ultimate analysis, and calorific value were determined to characterize and understand the physical conditions and coal properties during combustion. Results showed that blending torrefied sugarcane (S. officinarum) bagasse with Semirara coal would generally improve its quality in terms of its combustion properties thereby making these combinations of coal and biomass advantageous.

Looking at the feasibility of using rice (Oryza sativa) straw locally known as “dayami”, which the Philippines is quantitatively abundant, for power generation could help farmers reduce production cost and minimize the postharvest waste. Hence, this study’s objective is to provide a detailed knowledge of the physical and chemical properties of Philippine coal blended with torrefied rice (O. sativa) straw to efficiently use biomass for energy production. Proximate, ultimate, and calorific value analyses showed that rice (O. sativa) straw like other biomass resources are appropriate to meet the requirement of thermochemical process. When compared to pure coal, agricultural residues biomass like rice (O. sativa) straw has lower moisture and ash content, likewise nitrogen and sulfur are very low as well. Generally, blending Philippine coal with torrefied rice (O. sativa) straw would improve its quality in terms of its combustion properties thereby making these combinations of coal and biomass advantageous.