ICCT commissioned this study by Dr. Christopher Teh Boon Sung, a professor at the University Putra Malaysia, to review and assess the environmental implications of removing palm residues from plantations for use as a biofuel feedstock in Indonesia. Indonesia has been producing biofuel mostly from palm oil, and advanced biofuel from palm residues could offer a more sustainable, low carbon alternative.
In this study, Dr. Teh reviews different types of palm residues, including palm fronds, trunks, and empty fruit bunches, and the value they have as a soil amendment when left in the field. Palm fronds are trimmed from the trees every year, as well as when the trees are felled at the end of their lifecycle, and the fronds and trunks are left in the field. Fruit bunches are sent to the palm oil mill where the oil is extracted, and the empty bunches are typically returned to the field as mulch. All types of palm residues act as fertilizer, releasing nutrients when they decompose and reducing the amount of inorganic fertilizer that must be applied for healthy palm growth and oil yields. The residues also improve soil moisture retention and soil pH, and build soil organic carbon.
This study concludes that empty fruit bunches, as well as a small amount of palm fronds and trunks, can be removed from the plantations and used for biofuel without significant negative effects on plantation soil and future palm oil yields, as long as robust soil conservation methods are practiced. Exactly how much residues can be removed depends on local conditions, and that the sustainably available amount will vary among plantations.