Palm oil is being criticized as an unsustainable product by the EU due to its association with deforestation and high carbon emissions. However, the producers in Indonesia do not acknowledge the criticisms. Therefore, this study aimed to compare the carbon footprint of a representative EU-produced vegetable oil, rapeseed oil, with Indonesian palm oil. The analysis is divided into two stages, namely (a) land use conversion (LUC) as well as (b) plantation and oil processing. LUC entailed the conversion of native vegetation, such as forest areas and grassland, to vegetable oil crops. The carbon opportunity cost was used to account for the LUC contribution to the carbon footprint. For plantation and oil processing stages, the LCA SIMAPRO was adopted. The results showed that when vegetable oil replaced high-carbon-storage vegetation such as forests, the LUC carbon footprint of rapeseed oil and palm oil production were 2.09 and 1.49 t CO₂eq t⁻¹ oil, respectively. Replacing low-carbon-storage vegetation, namely shrub/grassland, led to 0.05 and −0.43 t CO₂eq t⁻¹ of repressed and palm oils, respectively. Based on the LCA SIMAPRO, the carbon footprints of plantation and oil processing stages were 1.05 and 0.88 t CO₂eq t⁻¹ oil for rapeseed and palm oils, respectively. The cultivation of oil palm in peatland generated a higher total carbon footprint (i.e., combined LUC and plantation and oil processing stages) than rapeseed oil (13.8 to 3.14 t CO₂eq t⁻¹ oil). However, in non-peatland areas, the total carbon footprint of palm oil was lower than rapeseed oil (2.37 to 3.14 t CO₂eq t⁻¹ oil) when replacing tropical forest and temperate forest vegetation, respectively. The total footprint was 1.2 to 0.45 t CO₂eq t⁻¹ oil when both replaced shrub/grassland. The higher productivity of oil palm and lower fertilizer requirement contributed primarily to the lower carbon footprint in non-peatland areas.

The yield of oil palm is heavily influenced by various climatic conditions, including rainfall (RF), radiation (Qs), temperature, and humidity. To quantify the impact of these factors, a study was conducted on a 15-year-old palm located in an oil palm estate in Pangkalan Lima Puluh Kota, West Sumatra, Indonesia. The study used climate data from 2011-2019 and yield data from 2015 and 2019. To determine the contribution of RF, Qs, and VPD / vapour pressure deficit, which was estimated from temperature and humidity, a computer-intensive importance metric developed by Lindemann, Merenda, and Gold (LMG metric) was utilized. The results showed that RF, Qs, and VPD collectively accounted for 50.16% of yield fluctuations at the study site. Furthermore, the contribution of climate factors on yield followed the order of VPD > Qs > RF.

The water requirement of oil palm depends on the growth phase (e.g., higher demand during vegetative expansion), environmental conditions (e.g., increased under high vapour pressure deficit), and agricultural practices (e.g., reduced demand through effective water management). Therefore, the water used for oil palm nurseries should be used efficiently to preserve environmental sustainability. The main objective of this research was to determine the water use efficiency (WUE) of oil palm during the main nursery phase. The study evaluated several irrigation strategies inside and outside the greenhouse, including fixed daily watering (two liters per seedling), irrigation based on actual evapotranspiration (ETa), rainfall-dependent watering, and no irrigation. In the outdoor treatments, one group of seedlings was irrigated according to ETa, but watering was withheld when daily rainfall exceeded five mm, while another group received two liters per day only when rainfall was below five mm. These two treatments showed the highest daily evapotranspiration rates, greater vegetative growth, and higher biomass accumulation compared to the other treatments. Notably, the ETa-based treatment was recorded as having the highest water use efficiency (WUE). This study concludes that water loss during evapotranspiration is the main determining factor for irrigation volume. Therefore, irrigation in oil palm nurseries should be based on ETa to improve efficiency and lower costs. These findings offer practical guidance for farmers or plantation management to support more sustainable and cost-effective irrigation practices.