Life Cycle Assessment of Greenhouse Gas Emissions: Comparison Between a Cooling Tower and a Geothermal Heat Exchanger for Air Conditioning Applications in Ecuador

Cooling towers are widely used to remove heat in buildings with chilled water air conditioning systems. Moreira et al. [1] performed an experimental comparison between a cooling tower (CT) and a geothermal heat exchanger (GHE) in Guayaquil-Ecuador (hot/humid climate) and the results show an advantage of 39% of GHE systems regarding energy efficiency. This study compares the emissions of greenhouse gases (GHG), considering the results of the research mentioned above and comparing both systems. A life cycle assessment (LCA) approach was used to estimate the GHG emissions, assuming three scenarios for the electricity supply: the electricity generation mix in 2016, the planned electricity generation mix in 2025, and the profile for marginal electricity generation (peak demand). The estimated reduction of GHG emissions due to the use of GHE systems could be up to 50%. GHEs for building air conditioning applications is a technological option with potential to reduce energy consumption and GHG emissions. However, additional work is necessary to evaluate the complete environmental profile and its cost-effectiveness.