Route For Energy Harvesting Research Articles

A breathable and woven hybrid energy harvester with optimized power management for sustainably powering electronics

Wearable hybrid energy harvesters show enormous potential for supplying power to wearable electronics since they circumvent the issue of discontinuous source energy of single energy harvesters and thereby supply more available energy. The hybridization of triboelectric nanogenerators (TENGs) and biofuel cells (BFCs) is promising; however, there are two major challenges. First, the two energy harvesters’ outputs are severely mismatched, but optimized power management and design principles have not yet been demonstrated. Second, previously reported devices are based on planar structures and lack breathability. Here, we develop a breathable and woven hybrid energy harvester (BWHEH) that is knitted with a textile TENG and fiber BFCs. A power management circuit is specially designed to match and optimize the output direct current power supply, which can enlarge the output power by ∼46.1 times, significantly lowering the effective internal impedance of the power source and improving the power delivery for common wearable loading conditions. The design principles of the power management for the TENG–BFC hybrid are thoroughly revealed. The wearable BWHEH self-charging power system can sustainably power various portable electronics by harvesting biomechanical and biochemical energy. This work provides a new route for energy harvesting and offers fundamental guidance for high-power hybrid energy harvesters.

Unusual impact of electron-phonon scattering in Si nanowire field-effect-transistors: A possible route for energy harvesting

In the current work, the impact of electron-phonon scattering phenomena on the transport behaviour of silicon nanowire field-effect-transistors with sub-mean free path channel length has been investigated by developing a theoretical model that incorporates the responses of carrier effective mass mismatch between the channel and source/drain. For this purpose, a set of relevant quantum field equations has been solved by non-equilibrium Green's function formalism. The obtained device current for a particular set of biases is found to decrease due to phonon scattering below a certain doping level of source/drain, above which it is observed to enhance anomalously. Analyses of the quantified scattering lifetime and power dissipation at various confinement modes of the device indicates that such unusual enhancement of current is originated from the power served by phonons instead of associated decay processes. The power generation has been observed to improve by using high-k materials as gate insulator. Such results may contribute significantly to the future nano-electronic applications for energy harvesting.

A Routing Protocol for Solar Energy Harvesting Wireless Sensor Networks

Energy and lifetime issues are crucial to the wide applications of wireless sensor networks. This paper proposes a routing protocol, SEHRP (Solar Energy Harvesting Routing Protocol), for solar energy harvesting wireless sensor networks. This protocol classifies all the sensor nodes into various regions for which each region has been assigned its transmission priority, and the data can only be delivered from lower priority regions to higher priority region. SEHRP can also detect the sensor nodes which are under the charging state, then avoid choosing those charging nodes to ensure the successful data delivery. Simulation results show that, compared to the baseline protocol, SEHRP can achieve significant performance improvements in terms of average energy consumption and average data delivery rate.