Alternative Heating, Ventilation, and Air Conditioning (HVAC) System Considerations for Reducing Energy Use and Emissions in Egg Industries in Temperate and Continental Climates: A Systematic Review of Current Systems, Insights, and Future Directions

Abstract

Egg production is amongst the most rapidly expanding livestock sectors worldwide. A large share of non-renewable energy use in egg production is due to the operation of heating, ventilation, and air conditioning (HVAC) systems. Reducing energy use, therefore, is essential to decreasing the environmental impacts of intensive egg production. This review identifies market-ready alternatives (such as heat pumps and earth–air heat exchangers) to traditional HVAC systems that could be applied in the industrial egg sector, specifically focusing on their use in temperate and continental climates. For this analysis, energy simulations were run to estimate the typical thermal loads of caged and free-run poultry housing systems in various Canadian locations, which were used as examples of temperate and continental climates. These estimations were then used to evaluate alternative HVAC systems for (1) their capability to meet the energy demands of egg production facilities, (2) their environmental impact mitigation potential, and (3) their relative affordability by considering the insights from a systematic review of 225 relevant papers. The results highlighted that future research should prioritize earth–air heat exchangers as a complementary system and ground source heat pumps as a stand-alone system to reduce the impacts associated with conventional HVAC system operation in egg production.