Energy harvesting as been an exciting area people have tried to venture into mostly because of the possible applications that can arise from it. Newly invented energy-harvesting technologies accompanying with low-power computing system have pushed the boundaries of where embedded systems can be deployed.
The demand for an increase in connected applications which requires an underlying embedded system, and as we know, all electronic devices require a power of some sort. This power needs, which mostly comes from DC batteries in most cases, comes with an accompanying buck regulator of some sort that will tend to increase the BOM.