This work aims to experiment with logical gates-based low-power voltage measurement circuits as a feasible alternative for Energy Harvesting applications. The motivation for doing so is to evaluate this energy measurement method in low-energy scenarios, in order to observe its accuracy and power consumption. In this kind of application, the stored energy level is relevant because it is not abundant, so energy efficiency is essential in every step. Our conclusion is that the use of discrete circuits for the VCO model presented by the Failure Sentinels work is unlikely to be fully implemented using the currently available discrete components in the market, especially for lower voltage values.