Recently, the buses in London are now powered by coffee, instead of fossil fuel.

Of course, we will not burn the coffee beans as fuel, but the coffee grounds instead, which is known as the leftover after brewing the coffee. It is the first time that coffee was tested to fuel the buses after cooking oil and tallow oil. This project aims to be an important step to reduce the toxic air pollution of London.

The company behind this revolution — bio-bean, is the first company in the world to industrialise the process of recycling wast coffee grounds into biofuels as well as biochemicals. According to the research, waste coffee grounds disposed via landfill emit methane, which is a greenhouse gas that is 28 times more potent than carbon dioxide. Of course, the habit of having a cup of coffee is not blamed, but we should notice that it has an impressive carbon footprint.

Recycle and reuse the coffee grounds is beneficial both economically and efficiently. First of all, the coffee grounds is always considered useless after the coffee is done and the grounds would be tossed into the trash bin and emit methane spontaneously during the landfill. This action of reusing the coffee ground would reduce the green gas emission as well as reduce the amount of waste. On the other hand, it is found that the coffee grounds have considerable high caloric output, it burns hotter and longer than wood and have 100% carbon-neutral environmental impact. After the coffee grounds is dried, the extracting coffee oil is mixed with solvent and then the solution is combined with other fuels into a hybrid B20 fuel, which could be used in diesel buses directly.

I am really impressed by this innovation as previously, no matter the hydrogen energy or electricity, people uses complicated process as well as additional energy consumption to produce these purified fuel, while the reuse of the coffee grounds would be much easier and require less useful resources. So next time, when you are having a cup of coffee, the journey of the coffee beans has not end yet.