Powering the IoT: Storage-less and converter-less energy harvesting

Wide spread of Internet of Things (IoTs) still have huddles in cost and maintenance. Energy harvesting is a promising option to mitigate battery replacement, but the current energy harvesting methods still rely on batteries or equivalent and power converters for the maximum power point tracking (MPPT). Unfortunately, batteries are subject to wear and tear, which is a primary factor to prevent from being maintenance free. Power converters are expensive, heavy and lossy as well. In this paper, we introduce a novel energy harvesting and management technique to power the IoT, which does not require any long-term energy storages nor voltage converters unlike traditional energy harvesting systems. Extensive simulations and measurements from our prototype demonstrate that the proposed method harvests 8% more energy and extends the operation time of the device 60% more during a day. This paper also demonstrates a UV (ultraviolet) level meter for skin protect, named SmartPatch, using the proposed energy harvesting method. The proposed method is not limited to photovoltaic energy harvesting but applicable to most energy harvesting IoT power supplies that require impedance tracking.