Biogas-Powered Evaporative Cooling for the Dairy Industry

Innovator (Country of Incorporation): 
United States
Smallholder Fortunes (Uganda)
Location Applied: 
Clean Energy Source: 
Agricultural Focus: 
Product Segment: 
Year of Award: 

The University of Georgia Research Foundation (UGARF) is a nonprofit entity housed within the University of Georgia in the United States that enhances UGA’s excellence as a research and higher education institution. Smallholder Fortunes is a small scale demonstration dairy farm located in Wakiso District, Uganda.


Throughout sub-Saharan Africa, the dairy industry suffers from lack of proper refrigeration options. Large dairies cannot export milk to neighboring markets due to international standards requiring milk be cooled within four hours of production. Small farmers may lose 20–50 percent of milk to spoilage due to lack of cold-chain facilities. There is limited access to electricity for refrigeration units, and kerosene and solar-powered options have proved too expensive and difficult to operate.

Clean Energy Solution: 

UGARF has developed a two-component device (branded as “EvaKuula”) powered by biogas—which is extracted from cow manure. The device delivers a mild heat treatment followed by gentle evaporative cooling process that keeps the milk fresh overnight. Partnered with Smallholder Fortunes, UGARF is refining the design of the refrigeration device, and testing it with farmers in Uganda. UGARF is working with local manufacturers to field-test the device and will secure financing and bring production of the units to commercial scale.


This project has numerous social, economic, and environmental benefits. It is an alternative to cold-chain facilities, as there is limited access to electricity, and kerosene and solar-powered options thus far have proved too expensive and difficult to operate in the local context. The EvaKuula is benefiting smallholder dairy farmers by decreasing milk spoilage and increasing production and profits and biogas for lighting and cooking. A fraction of the captured biogas is being used for lighting and cooking – saving income that would otherwise be spent on kerosene, and replacing the use of wood and charcoal for cooking. Also, by extracting biogas from cow manure, greenhouse gas emissions from fermenting cow manure is mitigated.

Progress Update: 

UGARF completed their project in March 2018. By the end of their Powering Agriculture participation, UGARF had deployed 43 EvaKuula units in Uganda: 42 benefitting farmers and one installed for research purposes at the Smallholder Fortunes farm. Half of the project beneficiaries are women, who have been successful users and provided important word-of-mouth marketing for the technology. User input was invaluable in the product design process, with input from women ensuring that the product incorporates factors that are female-friendly. UGARF hopes to expand into Rwanda in the future, and the group worked to transition from a project into a business by developing a business plan and pitching to investors. Next steps include continuing with value engineering to lower the manufacturing cost well below the price point for the units and scaling up as a formal business.

Project News: 
Final Innovator Reflections: University of Georgia Research Foundation (UGARF)
Mar. 12, 2020

Follow the story of EvaKuula and the innovator behind the technology, Dr. William Kisaalita, a professor at the University of Georgia whose nonprofit entity, the University of Georgia Research Foundation, developed a biogas-powered milk chiller benefits smallholder dairy farmers by decreasing milk spoilage and increasing production and profits and biogas for lighting and cooking.

Nov. 21, 2018

UGARF is being honored for the EvaKuula, their biogas-powered evaporative milk cooler. AE50 awards have been encouraging and applauding engineering achievements since 1984. Entries are evaluated by a blue-ribbon, international panel of industry experts in technology, design, and product development.