The increasing global warming temperature has caused pressure on all manufacturing companies to reduce their production emissions. Carbon dioxide (CO₂) remains the highest greenhouse gas that is emitted daily. The beer industry is among companies that utilise fossil fuels to generate energy for production. This study explores the energy efficiency improvement opportunities that exist in African breweries to reduce CO₂ emissions caused by beer production processes. To be able to identify improvement opportunities, the research determined the causes of high heat energy usage in the beer manufacturing process. Quantitative and qualitative secondary data and records from 10 African breweries of Company X were used to analyse the relationship that exists between heat energy utilisation and CO₂ emissions from breweries. High heat energy utilisation is caused by poor practices that exist in the breweries. The findings showed that when steam production has high boiler efficiency the total heat energy used will be reduced. The total steam usage by brewery processes and heat energy utilisation had a positive relationship. Statistical analysis showed a strong correlation between both boiler efficiency and steam usage with CO₂ emissions for most of the breweries. The findings highlighted the importance of breweries being able to identify sources of heat energy inefficiencies. For sustainable improvements, capital investment into energy-saving technologies can be explored when energy wasters are eliminated.