It is estimated that there will be 75 Billion IoT sensors in the world by 2020 [source Morgan Stanley] all needing a power source (e.g., temperature, light, humidity being low power, gas and occupancy sensing being high power). This brings to the fore the critical issue of limited battery life. In many cases it will not be feasible to access and service such parts due to quantity, location, cost, logistics, etc.
An additional attraction of autonomous powering is the ability to have independent wireless sensors that can be placed on, in or near equipment or infrastructure to monitor behaviour and report anomalies, thereby enabling predictive and preventative maintenance. This enables manufacturers and service providers of power electronic systems to enhance reliability of such equipment and the applications they serve, opening up additional revenue streams.