Recently [G. D’Abramo, Phys. Lett. A 374 (2010) 1801] the concept of vacuum capacitor spontaneously charged harnessing the heat from a single thermal reservoir at room temperature has been introduced, along with a mathematical description of its functioning and a discussion on the main paradoxical feature that seems to violate the Second Law of Thermodynamics. In the present paper we investigate the theoretical and practical possibility of exploiting such a thermo-charged capacitor as voltage/current generator: we show that if very weak provisos on the physical characteristics of the capacitor are fulfilled, then a non-zero current should flow across the device, allowing the generation of potentially usable voltage, current and electric power out of a single thermal source at room temperature. Preliminary results show that the power output is tiny but non-zero.