OBJECTIVES::  Recently, Brazil experienced the worst drought of its history. In addition, hydropower management issues have contributed to a price increase of electricity - an average increase of 83.23% in two years. As a consequence, sustainable alternatives for reducing the waste of natural and financial resources are needed. Within the hospital environment, there is a discussion about the sterilization with hydrogen peroxide technology as a sustainable alternative. In order to evaluate the potential benefits of this technology a simulation of the economy generated with the replacement of Ethylene Oxide for Hydrogen Peroxide in midsize hospitals (approximately 80 sterilization cycles per month) in the state of São Paulo was conducted. METHODS::  The analysis was divided in four phases: (i) Understand the water and energy resources used in each of the technologies; (ii) Evaluate the composition of costs of water and energy; (iii) Estimate the total costs per sterilization cycle for each technology; (iv) Compare the monthly and annual total costs of each technology. RESULTS:: From the perspective of water consumption, at the end of a year, the total cost of the Hydrogen Peroxide was R$0.00 while the total cost of the Ethylene Oxide was R$6,633.72 (US$1,895.34 – USD3,50). From the perspective of energy consumption, at the end of a year, the total cost of the Hydrogen Peroxide was R$444.14 (US$126.90 – UDS3,50) while the total cost of the Ethylene Oxide was R$38,626.79 (US$11,036.25 – USD3,50). In terms of kilowatt consumption, Hydrogen Peroxide used only 1.1% of the kilowatts consumed with EtO. CONCLUSIONS:: The sterilization with Hydrogen Peroxide is a sustainable alternative, reducing natural and financial resources and then, contributing to hospitals’ concerns related to sustainability.