We live in a world with scarce resources, one of which is fossil fuel. If there is one thing that everyone has come to understand over the past several years is that we need to make amends to give a chance to our environment that we have severely damaged a chance to recover. Nearly all developed countries are laying the groundwork for a clean mobility revolution, and India has also started to implement the necessary adjustments.
Introducing electric cars has sparked a change that will encourage environmental responsibility among people while providing benefits like cleaner air and financial stability by shielding them from the shocks of gasoline costs. However, the question remains whether that is sufficient and environmentally friendly and whether any other sources that the world could look upon are available.
Biodiesel is one such alternative. It is a second-generation biofuel and is a form of diesel produced by vegetable oils and fats such as palm oil, jatropha, etc., by adding methanol through the transesterification process, which is why it is also called methyl esters.  It can be used in diesel motor vehicles, making it an ideal replacement fuel for non-sustainable diesel. 
The rising prices of petroleum products, greenhouse gas emissions, and reducing the crude import bill bring in the shift to biodiesels.  The main reasons that gave biodiesels an easy acceptance are the characteristics which make them environmentally, socially, and economically viable and sustainable fuels
It is also bio-degradable and renewable in nature. 
Process of Formation
Biodiesels can either be produced through natural phenomena or controlled mechanisms. Natural wonders like Krebs Cyclers and Diacylglyceride can be used, whereas transesterification and esterification are some of the controlled methods.  sup>Biodiesel is a substitute fuel which is a blend of biofuel and diesel. Biofuel blends are a combination of biofuels and fossil fuels like gasoline or diesel. B2 (2% biofuel and 98% fossil fuel), B5 (5% biofuel and 95% fossil fuel), and B20 (20% biofuel and 80% fossil fuel) are three prevalent biofuel mixes. Ethanol and biodiesel are the most often utilised biofuels in mixing. The blending of biodiesel requires moderate or high temperatures; it cannot be carried out at cold temperatures, which makes most Asian and Gulf countries suitable as a location for it. 
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One of the major concerns for biodiesel is its storage issues. Esters with long oleic, linoleic, or linolenic acid chains are found in biodiesel.  These fatty acids are prone to oxidation and forming lengthy polymer chains when stored in a metal container; hence, there is a need to add antioxidants. Adding antioxidants such as pyrogallol, propyl gallate, and butyl hydroxy anisole in biodiesel can increase the shelf life of biodiesel. Biodiesel can deteriorate its quality without an antioxidant within a week or so, and studies suggest that with the use of antioxidants, it can be stored for as long as one month.  Antioxidants play a vital role in the stability of biodiesel, leaving no harmful impact on its properties. The effect of the antioxidant is proportional to its concentration.
As the world’s largest biodiesel producer, Indonesia serves as the epicentre of the biodiesel market. It demonstrates their dedication to lowering greenhouse gas emissions and considerably boosting their country’s economy.  Not only Indonesia’s biodiesel production is the largest in the globe (combined with its’s significant palm oil industrial setup), but also the country has an excellent agricultural setup for the raw ingredients of biofuel linked to its topography. To reduce energy imports and promote palm oil consumption, Indonesia’s Energy ministry aims to test two types of B40 blending – one using 30% Fatty Acid Methyl Ester (FAME) and 10% distilled Palm Methyl Ester (DPME) and another using 30% FAME and 10% green diesel made from palm oil. 
Despite unfavourable climatic conditions, the USA is the world’s second-largest biodiesel producer. The USA has long had a dominant position in the energy industry, and any changes they make tend to impact the global energy market. Fuel Bio has built the largest biodiesel-producing facility on the east coast of the United States, with an average capacity of 300 million gallons. REG and Marathon Petroleum are two of the biggest producers of biodiesel in the USA. As a result, the USA becomes less reliant on foreign fuel imports and gains energy independence.
India has huge untapped potential when it comes to biodiesel and its production, although with a rising population, India faces enormous challenges related to using land to grow food as against growing for fuel. However, due to climatic conditions, geography, and recent technological advancements, India could become the global leader in biodiesel production. This will also help the country to curb its carbon emission and will work as a stepping stone in its commitment to India to become carbon neutral. 
In 2006, the Ministry of Petroleum and Natural Gas announced the biodiesel purchase policy to advocate the blending of biodiesel in diesel and for marketing and retail sale of biodiesel in retail outlets.  The policy also ensures the strengthening of India’s bio-future platform with an agenda to promote a sustainable future. The increasing demand for sustainable fuels in the automotive industry and growth in the number of vehicles driven by biodiesel is disrupting the demand-supply chain, eventually drawing the government’s attention to the matter and resulting in various policies and schemes. In India, the market for the biodiesel industry is growing at a rate of 8%, with a market volume of 0.17 million tonnes as of 2021.
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The exponential demand growth for biodiesel is evident in most developing countries and worldwide. Given its versatility for use in existing engine modules, biodiesel is an exceptionally promising fuel that might be the solution to the now well-recognised threat of environmental damage caused by automobile emissions.