The Horn of Africa Regional Environment Center and Network (HoA-REC&N) is an autonomous institution under Addis Ababa University. HoA-REC&N focuses on environmental concerns and sustainable development options within the Horn of Africa. Partner institutions include University of Hohenheim; University of Massachusetts–Boston; and the Oromia Coffee Farmers Cooperative Union.
Coffee accounts for 60 percent of the export earnings in Ethiopia, and is processed by dry and wet processing. Wet processed is preferred in the global market. Unfortunately, farmers do not see the full benefit of their coffee production. A significant portion of coffee harvested is of inferior quality due to the traditional sun drying process. This process can take up to twelve days and increases exposure of coffee to fungi and other undesirable elements. Thermal drying is energy intensive and takes up a large amount of space.
The proposed solution uses state of the art infrared technology to reduce coffee pulp drying time from several days to hours. Reduced drying time minimizes the post-harvest loss that occurs when using the conventional sun drying process. Biogas generated from coffee pulp and coffee husk will be used to power the bioreactors used for infrared drying.
The success of this project will lead to new opportunities that can transform the current traditional coffee production system while improving the quality and quantity of coffee. By reducing the time farmers spend in coffee processing, the time saved can be used for other productive uses which will help them generate additional income. The project will also improve work conditions for women and children, who are primarily responsible for the sun drying process which requires all-day exposure to the sun.
HoA-REC&N has been working on developing a biogas digester and an Infrared (IR) Dryer to dry coffee beans. Over the past few months HoA-REC&N constructed and commissioned four bio digesters which were tested with two different coffee feedstocks–husk and pulp. The tests showed that the coffee pulp resulted in higher yields of bio-methane. Additional experiments were conducted to analyze the effectiveness of coffee drying at different temperatures and power. In collaboration with one of their partners, University of Massachusetts-Boston, HoA-REC&N has finished putting together technical specifications for the IR Dryer. Finally, HoA-REC&N has selected the Kenterie coffee cooperative, comprised of 1520 members, as the site to pilot their technology.