Energy Harvesting from Ambient Vibrations and Heat

Abstract

Increasing demand in mobile, autonomous devices has made the issue of energy harvesting a particular point of interest. Systems that can be powered up by a few hundreds of microwatts can feature their own energy extraction module, making them truly self-powered. This energy can be harvested from the close environment of the device. Particularly, piezoelectric conversion is one of the most investigated fields for ambient energy harvesting. Moreover, the extraction process can be optimized by proper treatment of the piezomaterial output voltage. This article proposes a detailed explanation of the real energy flow that lies behind several energy conversion techniques for piezoelectric energy scavenging. As well, the principles of energy harvesting using piezoelectric effect is extended to the pyroelectric effect, therefore allowing harvesting energy from temperature variation, which is one of the most common energy sources.

Recent Progress in Piezoelectric Conversion and Energy Harvesting Using Nonlinear Electronic Interfaces and Issues in Small Scale Implementation

“…Finally, it can be noted that the concept of the nonlinear operation is independent from the physical phenomenon (as long as one quantity is continuous), allowing its application to other conversion effects [28,39,40].…”

“…In this field, Guyomar et al introduced a simple, low-cost process to artificially enhance the coupling coefficient of electromechanical systems using piezomaterials [17][18][19][20][21][22]. Based on a simple nonlinear process of the output voltage of the active material, this approach, initially developed for vibration damping purposes [23][24][25][26][27], permits a gain of up to 20 in terms of energy conversion, and 10 in terms of harvested energy [28]. Several techniques derived from this original method have been proposed, each of them addressing a particular concern (broadband vibration, impedance matching, energy harvesting ability enhancement, etc.…”

Electrostrictive Polymers for Vibration Energy Harvesting

“…200 Small-Scale Energy Harvesting Because of the similarities between electrostrictive polymers operating in dynamic mode and piezoelectric element, it is also possible to apply nonlinear processing to artificially enhance the conversion abilities of the material ( [41][42][43][44][45][46][47]). The principles of this treatment consist in (imperfectly) inverting the active element voltage (with reference to the bias voltage) each time a maximum or a minimum strain value is reached (Figure 14), by briefly connecting the material to an inductance (hence shaping a resonant electrical network).…”

Load-Tolerant, High-Efficiency Self-Powered Energy Harvesting Scheme Using a Nonlinear Approach

“…Hence, in order to counteract the limitations introduced by the batteries, a lot of attention has recently been placed on systems able to provide electrical energy using ambient sources (Kahn, Katz, and Pister 1999;Krikke 2005;Yildiz 2009), such as thermal (Sodano et al 2006;Ujihara, Carman, and Lee 2007;Guyomar et al 2009;Sebald, Guyomar, and Agbossou 2009), photonics (Hamakawa 2003) or vibrations (Shearwood and Yates 1997;Stephen 2006), giving birth to the "energy harvesting" concept. Among all of the aforementioned sources, vibrations are of particular interest in the scientific community for powering small-scale devices (such as consumer electronics or sensor network nodes), as such a source is commonly available in many environments.…”