Investigating the Opportunities for Environmentally Benign Options in the Refrigeration Industry of Uganda
Thomas Makumbi *
Faculty of Engineering and Sustainable Development, University of Gävle, Kungsbäcksvägen 47, 801 76 Gävle, Sweden and Department of Electrical and Computer Engineering, College of Engineering, Design, Art and Technology, Makerere University, P.O.Box 7062 Kampala, Uganda
John Baptist Kirabira
Department of Mechanical Engineering, College of Engineering, Design, Art and Technology, Makerere University, P.O.Box 7062 Kampala, Uganda
Adam Sebbit
Department of Mechanical Engineering, College of Engineering, Design, Art and Technology, Makerere University, P.O.Box 7062 Kampala, Uganda
Björn Palm
Department of Energy Technology, The Royal Institute of Technology (KTH), Brinellvägen 68, SE-100 44 Stockholm, Sweden
*Author to whom correspondence should be addressed.
Abstract
Using synthetic refrigerants has led to ozone depletion, global warming and the associated climate change. This study therefore aimed at investigating the application of environmentally friendly options in the refrigeration industry of Uganda with the main emphasis on refrigerants. A field study was done to assess the current status of refrigeration in Uganda as well as to obtain relevant information for the study using questionnaires, interviews, field measurements and observations. The required data included evaporation and condensing temperatures and pressure, refrigerant mass flow rate, system type, refrigerant type, etc. Using the above data as input, models of the available systems were developed using EES and their efficiencies determined; also, models were proposed for each sector in the industry using an appropriate natural refrigerant(s) and comparison of the efficiencies obtained with those of installed systems was made. EES also assisted in the performance of a parametric study on the system operating parameters. Results from the field survey showed that synthetic refrigerants dominate the industry and the systems installed are single stage vapor compression while those from modeling and simulation reveal that natural refrigerants offer a promising solution in the refrigeration industry of Uganda and should be adopted for energy, safety and environmental reasons. Nevertheless, it is recommended that rigorous testing of the systems with alternate refrigerants proposed be conducted to verify the results of the simulations before full adoption. Furthermore, performing an economic analysis would give better justification for adoption from an industrial point of view. However, the major challenges to be encountered in case of adoption are safety, system modifications especially in systems that are to use R744, lack of technical expertise to design, install, operate and service the systems as well as lack of government policy to spearhead the transition. Therefore for the transition to be realized there is need to come up with policy concerning the use of environmentally harmful refrigerants and also create awareness in the industry.
Keywords: Environmental friendliness, refrigeration, refrigerants, greenhouse, EES, Uganda