Biodiesel is an alternative fuel derived from the fats of animals and plants. As energy demands increase and fossil fuels are limited, more research has been devoted to the use of alternative renewable fuels in recent years. As well as the fact they are renewable, biofuels have the advantage of being more environmentally friendly and producing less harmful exhaust gases when used in compression ignition engines.
Neem has been identified as one of the most promising environmentally friendly alternatives to fossil fuels. It is an evergreen tree, native to India, that is used as a natural ingredient in cosmetics, as an additive to livestock feed, as a natural pesticide and fertiliser, in pet care products, and even in healthcare treatments. Every part of the tree can be used – the leaves, the bark, the flowers, the gum, the fruit, and the seeds. The seeds are pressed to make neem oil, they contain 45% oil which makes it the perfect candidate for biological engine fuel.
Can biofuels perform in a commercially competitive world?
Biofuels contain a high amount of water and oxygen, which have a corrosive effect on engines. Hybrid car fuels such as the E10 which contain a mixture of 10 percent ethanol and 90 percent gasoline, very quickly became unpopular amongst motorists as they were suspicious it could damage their car engines. The oil industry doesn’t believe biodiesel is to blame for the problems reported with engines but not everyone agrees, and even if research does eventually prove this to be a myth, or engine modifications mitigate any risk, reputationally, biofuels like neem oil are already on the back foot.
Biofuels are less stable than petrol, and are susceptible to deterioration over time, particularly if exposed to light, humidity and temperature changes. This means that standards for storage and handling will need to be set if the fuel is used commercially in engines.
Environmental impact of growing and harvesting neem trees
There have been increasingly stringent environmental regulations for biofuels in recent years – sustainability criteria stipulate that biofuel must provide tangible reductions in CO2, not affect biodiversity or food production. Fertiliser, water and land are needed to grow neem trees and these processes make demands on the earth’s resources.
The Department of Mechanical Engineering in Abu Dhabi tested mixtures of neem biodiesel and petroleum diesel corresponding to neem additives of 5%, 10%, 15% and 25% for combustion efficiency and emitted gases using a high-performance gas analyser. The results were encouraging, particularly for the 10% blend – is 10% enough to make any difference when we are already in the midst of a climate emergency? Will the public perception of biofuels change enough for it to become a commercially viable prospect?
The fact. However, remains we don’t have an unlimited amount of fossil fuel, so alternatives need to be found, and neem is showing promise.