A recent study discovers the potential and reality of transforming waste fruits and vegetables into usable electricity for citizens in Indonesia. In an effort to reduce the dependence on fossil fuels for energy and make best use of the waste generated by a population, researchers have created a system that takes in leftover food, creates biogas, and produces electricity as a final product. This system is much more sustainable than processing food waste in a landfill and releases roughly half of the emissions. In addition, the creation of biogas for electricity has a smaller processing cost than that of a landfill and the owner of the biogas system can earn a profit by selling the electricity made.
Biogas is a form of biofuel that is created via anaerobic digestion when bacteria breaks down organic matter and releases gases such as methane and carbon dioxide. The methane produced can then be turned into gas for your home or electricity.
Researchers used organic waste from one of Indonesia’s largest markets, evaluated it, and conducted an experiment to determine how they would create a pilot biogas system for the local government and its partners. During the experimental period, mango was used in conjunction with cattle dung and water to determine the correct amount of solids and liquids in the biogas digester. The amount of waste produced by the market was analyzed to find an appropriate amount that the biogas plant should be built for. The market varied from producing 4 tons to 20 tons of food waste per day depending on seasonal factors. Therefore, researchers decided to build the system to digest 4 tons per day.
The plant generated 733 kWh of electricity per day, which is slightly smaller than the amount a typical U.S. home uses per month. Once the gas is produced and electricity made, some residue remains in the digester. This residue can be used as a fertilizer or as a form of irrigation, such as in the study where the leftover liquid was used on nearby farms to irrigate fields.
Making the most of what we have is one way that society can curb the effects of climate change and limit our use of raw natural resources.
Source: Ariyanto T., et al. 2017. UTILIZATION OF FRUIT WASTE AS BIOGAS PLANT FEED AND ITS SUPERIORITY COMPARED TO LANDFILL. International Journal Of Technology 8: 1385-1392