ABSTRACT:
Climate change is considered by the World Health Organization as the greatest public health threat of the the 21st century. Paradoxically, healthcare sector exacerbates this, accounting for approximately 5% of global greenhouse gas (GHG) emissions. This highlights the need to implement sustainable and low-carbon solutions in hospitals. This descriptive study presents a documentary and institutional analysis of climate mitigation and adaptation actions implemented over a ten-year period in a large Brazilian public hospital. Since 2015, the Hospital das Clínicas da Faculdade de Medicina de Botucatu (HCFMB - countryside of the state of São Paulo, Brazil) has been monitoring its GHG emissions using GHG Protocol. In 2018, emissions increased by 22% compared to the previous year due to nitrous oxide (N₂O) leak in the operating rooms, representing 55% of total GHG emissions. An interdisciplinary committee was established and corrective measures reduced N₂O emissions to 29% in 2019 and 8% in 2024, with savings of $70,000. In 2024, the use of N₂O was completely discontinued in partnership with the anesthesiology department. Between 2015 and 2020, total hospital emissions were reduced by 33.4%. In 2021, HCFMB joined the Race to Zero initiative. In the same year, Scope 2 (energy) increased, representing 39% of GHG emissions. An energy efficiency project was developed and awarded approximately $2,000,000 by the Brazilian National Energy Company. The project focused on main actions: modernization of air conditioning systems, more efficient conservation chambers, LED lighting retrofit, and and installation of the largest rooftop photovoltaic power plant in Brazilian hospitals. These actions resulted in annual savings of 2,642.68 MWh, avoidance of 886 tCO₂/year, and a 19.2% reduction in total emissions by 2024. The HCFMB experience demonstrates that hospitals can and should act as strategic agents of climate action, promoting planetary health by integrating healthcare delivery with climate mitigation and adaptation.