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: 
Financing Status: 

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. The EvaKuula is benefiting smallholder dairy farmers by decreasing milk spoilage and increasing production and profits. 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 deployed the first two units with two female dairy farmers last March. Income for both these farmers has increased as a result of EvaKuula adoption. When asked about impact, one of the farmers said “I have been sending my granddaughter to sell our evening milk, door-to-door, after she comes back from school. Most of the time she would manage to sell one to two liters per day, out of the 10 or so liters we harvest in the evening. We consume some of the unsold milk and the rest given freely to the neighbors and/or workers on the farm. Sometimes all the milk just gets spoilt when my granddaughter gets home late and I can’t send her out in the dark. Where has this technology been all these years!!!?” Seven contracts are in hand to supply EvaKuula units in October 2016. UGARF has participated in a trade show in Kampala and a training of over 70 farmers. Based on demand generated by these activities, UGARF anticipates deploying approximately 10 units per month.

[See EvaKuula Facebook page.]

Project News: 
4th Microgrid Global Innovation Forum

Andrew Varrow of Development Ventures—a University of Georgia Research Foundation project partner—will discuss how microgrids can help eliminate energy poverty in the developing world, and outline strategies for encouraging private-sector investment in community-level microgrids. 

Aug. 5, 2015

The University of Georgia’s William Kisaalita discussed the challenges of developing a reliable cold chain in Uganda in a recent article on NPR’s The Salt, “Why You Shouldn’t Take Your Milk’s 3-Week Shelf Life for Granted”

William Kisaalita on Winning a 2013 Powering Agriculture Award
Jun. 26, 2014

William Kisaalita of the University of Georgia Research Foundation discusses their refrigeration unit powered on biogas extracted from cow manure. Reusable zeolite plates capture water vapor from the evaporative milk chilling process.