The remaining capacity of a power source, such as a battery, may be monitored with a microprocessor by integrating data received from a current sensor. The microprocessor may measure electrons passing through the battery by sampling the integrator and summing the values recorded from the integrator. Each time the integrator is sampled, the microprocessor may reset the integrator to prevent the integrator from saturating. The microprocessor may sample the integrator when the integrator approaches a predetermined value. The remaining capacity of the battery may be calculated based on calibration values and the sum of electrons measured by the integrator. The remaining capacity may be communicated to remote users through a network and displayed in an executive dashboard.