Life cycle assessment of instant coffee production considering different energy sources

Abstract

Nowadays, coffee is a popular beverage globally and one of the largest traded commodities. Conventional instant coffee production requires energy and water, producing coffee bagasse (biomass) as an agro-industrial residue. This residue, spent coffee grounds (SCGs), in Ecuador is currently disposed of in the municipal landfills, losing the opportunity to recover energy and minerals. This paper studies the life cycle environmental impacts of instant coffee production using data from a coffee plant in Guayaquil, Ecuador. The study analyzes the impact of generating the required electricity by an internal combustion engine powered by fossil fuel, using the Ecuadorian power grid, or using a combined cooling, heat, and power (CCHP) trigeneration system powered by dried SCGs and natural gas. The results indicate that when SCGs is used to power auxiliary processes, the CO2 emissions greatly decrease, helping to reduce fossil fuel dependence. The study also reveals that scenarios using electricity from the Ecuadorian power grid exhibit lower environmental indicators than those using internal combustion engines. The scenario that includes the CCHP records the lowest indicator in each category, reducing the GWP by 45.2 % compared to the base scenario, pointing out that using energy-efficient technologies lowers the carbon footprint, contributing to decarbonisation simultaneously.

Keywords

• Coffee
• Spent coffee grounds
• Bioenergy
• Trigeneration
• LCA
• Carbon footprint