Renewable Energy-Powered Bulk Milk Cooling for Smallholder Dairy Farmers

EPA Grant Number: SU836006
Title: Renewable Energy-Powered Bulk Milk Cooling for Smallholder Dairy Farmers
Investigators: Kisaalita, William S.
Institution: University of Georgia
EPA Project Officer: Nolt-Helms, Cynthia
Phase: II
Project Period: August 15, 2011 through August 14, 2012
Project Amount: $75,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet - Phase 2 (2011) Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Agriculture , P3 Challenge Area - Energy , P3 Awards , Sustainability


In Phase I, we constructed and tested the first generation (proof-of-concept) cooler, as well as established the optimal temperature at which the zeolite is completely regenerated. Successful completion is expected and the follow-up specific objectives for Phase II are as follows:

  1. Construct and start-up a cow-dung anaerobic digester to produce biogas and demonstrate that the regeneration of zeolite can be accomplished under this field condition.
  2. Install a second generation renewable-energy (biogas) powered milk cooler on a small-scale dairy farm and show that the cooling achieved in the laboratory (to 4°C within 4 hours) can be replicated under field conditions and establish the cooling cost per liter of milk.
  3. Establish the greenhouse gas (methane) production from smallholder farm cow dung open pits.


We will used the knowledge gained from the performance of the first prototype and the electric regeneration of zeolite in Phase II to design a second generation cooler that will be coupled to an oven for zeolite regeneration with biogas. We have established a partnership with Smallholder Fortunes, a small-scale dairy farm, located in Wakiso District. The farm operates six milking cows and houses a small milk quality assessment laboratory. We will first construct a 24 m3 digester and will use the available cow-dung to start and run the digester to produce biogas. We will then install the second generation large capacity cooler on the farm. The biogas from the digester will be used to regenerate the zeolite and the balance will be available for cooking and lighting on the farm. For the methane release studies, three open pits close to Smallholder Fortunes will be identified and a gas collection apparatus will be installed and used by the students. The Smallholders Fortunes technician will continue to analyze the quantity of methane produced once the students leave.

Expected Results:

We will show that the cooler can successfully add the evening milk to the cold chain and that it’s wide spread use has potential to reduce the amount of methane released into the atmospheres from smallholder dairy farms.

Supplemental Keywords:

Service-learning, STEM (science, technology, engineering, and mathematics), Social entrepreneurship, Food security, Sub-Saharan Africa, Sustainable development Environmental sustainability, Smallholder or small-scale or small-acreage farmers, Diffusion of technological innovations;

Progress and Final Reports:

  • Final

  • P3 Phase I:

    Renewable Energy-Powered Bulk Milk Cooling for Smallholder Dairy Farmers  | Final Report