Electricity and Hydrogen Generation from Food and Vegetable Wastes – Technical and Economic Analysis

The city of Guaratinguetá, Brazil, produces 104 tons of MSW daily, 45.3% of which is its organic fraction, and the rest is divided between recyclable material and waste without use. This study proposes the calculation of the biogas production potential from the anaerobic digestion of the Organic Fraction of Municipal Solid Waste (OFMSW). This fraction is mainly composed of food residues, such as fruits and vegetables, as well as paper and cardboard, among others, being a compound able to be processed in a biodigester. A production potential of 3,1 Nm3 of biogas per day, or 3,6 kg/day, was calculated. An electricity generation potential of 6.3 MWh/day was calculated. Considering the use of all this electrical potential in a water electrolysis process, a production potential of 107 kg/day of electrolytic hydrogen was calculated. An economic analysis of electricity generation is carried out, resulting in a cost of electricity between 34.7 and 41.2 USD/MWh, depending on the interest rate applied. The payback of the investment in electricity generation was calculated between 3 and 4 years, considering the local electricity tariff of 74 USD/MWh.