Biodiesel utilization has been rapidly growing worldwide as the prime alternative to petrodiesel due to a global rise in diesel fuel demand along with hazardous emissions during its thermochemical conversion. Although

several debatable issues including feedstock availability and price

fuel and food competition

changes in land use and greenhouse gas emission have been raised by using edible as well as inedible feedstocks for the production of biodiesel. However

non-crop feedstocks could be a promising alternative. In this article

waste cooking oils have been recommended as a suitable option for biodiesel production bearing in mind the current national situation. The important factors such as the quantity of waste cooking oil produced

crude oil and vegetable oil import expenses

high-speed diesel imports

waste management issues and environmental hazards are considered. Moreover

process simulation and operating cost evaluation of an acid catalyzed biodiesel production unit are also conducted. The simulation results show that the production cost of waste cooking oil-based biodiesel is about 0.66USD·L

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. We believe that the present overview would open new pathways and ideas for the development of biofuels from waste to energy

approach in Pakistan.