Here is the list of environmental disadvantages of biodiesel:

• The cost of biodiesel is one and a half times expensive than the existing petroleum diesel.
• It requires a lot of energy to produce biodiesel from soybeans. It includes the power of sowing, fertilizing, and harvesting.
• In some cases, it can damage the rubber hoses in the engines, especially in the cars that were built before 1994.
• Biodiesel can clean the dirt from the filter, but these can get clogged in the fuel filter. Usually happens when biodiesel is used in the engine that has been using petroleum diesel for a long time.

(edited 2-Dec-2019)