The invention relates to a gas volume converter comprising at least a temperature sensor (1) and a calculation unit (2) for delivering a value (V b ) of cumulated gas volume converted to a reference temperature condition. According to the invention, said converter comprises pulses generating means (3, 4) for delivering, without requiring electrical power, electrical pulses (S puls ) upon motion of a gas meter output element (5), each electrical pulse being representative of a unit volume of gas flowing through the gas meter; and power storage means (6) for storing voltage of said electrical pulses. The temperature sensor (1) and the calculation unit (2) are powered by the stored voltage delivered by said power storage means (6) to perform respectively a measurement (θ) of the temperature and a calculation of said value (Vb) from counting of the number of electrical pulses generated by said pulses generating means (3, 4) and from temperature (θ) measured by said temperature sensor (1).
Advantage: avoid the need of a separate power supply (battery or mains)