Cascaded pyroelectric energy converter

Harvesting Nanoscale Thermal Radiation Using Pyroelectric Materials

“…Moreover, performance of pyroelectric energy converter can be significantly improved by using heat regeneration and multistages along with the Olsen cycle [2][3][4][5]. To date, only five prototypes of pyroelectric converters have been built.…”

“…They used lead zirconate titanate (PZT) as pyroelectric materials and silicone oil as the working fluid while they operated between 145 • C and 178 • C [4]. Later, Olsen et al [3] assembled the only multistage device built to date using different grades of lead zirconate stannate titanate (PZST), in which Ti 4+ was substituted by Sn 4+ , for a maximum output of 33 W/L of pyroelectric materials at 0.26 Hz and featuring a maximum thermodynamic efficiency of 1.05% at 0.14 Hz or 12% of the Carnot efficiency. Moreover, due to the cost of PZT ($10,000/Watt), Olsen et al [6] proposed to use inexpensive single stage 73/27 P(VDF-TrFE) films of 30-70 µm thick sandwiched between electrodes and rolled in a spiral stack placed into a cylindrical chamber containing silicon oil.…”

“…Ceramic stacks were used to reduce axial heat conduction and ensure laminar flow of the working fluid over the pyroelectric elements as turbulence would results in mixing of the cold and hot fluid and disrupt the oscillating temperature gradient. Theoretically, pyroelectric conversion based on heat regeneration and the Olsen cycle can reach the Carnot efficiency between a hot and a cold thermal reservoir [3,24]. Limitations in reaching the Carnot efficiency include (i) hysteretic and resistive losses, (ii) heat losses to the surrounding, and (iii) sensible (thermal) energy.…”

“…In fact, in 2002 more than 50% of the net primary energy resource consumption in the U.S. was lost mainly in the form of waste heat [1]. Pyroelectric energy converter offers a novel direct energy conversion technology by directly transforming waste heat into electricity [2][3][4][5][6][7][8][9][10][11][12]. It makes use of the pyroelectric effect to create a flow of charge to or from the surface of a material as a result of successive heating or cooling cycles [13].…”

Reversible Switching of Icing Properties on Pyroelectric Polyvenylidene Fluoride Thin Film Coatings

“…Certain polymers have been suggested by others to be economically priced ice repellent coatings, which can be used in large-scale-production. With regard to renewable energy pyroelectrics, polymers in general as well as the investigations the polyvenylidene fluoride/trifluorethylene copolymer (P(VDF-TrFE)) have been suggested in particular to be a good material for energy harvesting from waste heat [28,29] by means of the Olsen cycle [30].…”