An octo-generator for energy harvesting based on the piezoelectric effect

N. V. Viet, M. Al-Qutayri, K. M. Liew, Q. Wang

Research output: Contribution to journalArticlepeer-review

24 Scopus citations


A renewable energy harvester using the piezoelectric effect is developed for the ocean tidal and wind flow. The harvester is made of connected driving blades to an octo-generator, which has a rotator with n blades and a stator attached by eight mass-spring-piston-cylinder-piezoelectricity devices. The resonance and force magnification are utilized to increase the power output of the harvester. A corresponding mathematical model is developed to calculate the root mean square of the generated electric power. The simulation results indicate that the generated power is largely enhanced when the near-resonant condition is established. The power increases with increases in the magnetic flux density, the large-to-small diameter ratio of the cylinder, the size of magnetic bar face, and decreases in the gap between two magnetic faces and the size of the piezoelectric bar face. A generated power of 5 kW is realized by the harvester working under an ocean tidal speed, V = 1.75 m/s, and its geometric and material properties of driving length L = 7.5 m, spring constant kv = 65000 N/m, gap between the two magnets s = 0.0015 m, large to small diameter ratio of the cylinder z = 6, and magnetic flux density Br = 1.45 T.

Original languageBritish English
Pages (from-to)128-134
Number of pages7
JournalApplied Ocean Research
StatePublished - 1 Mar 2017


  • Energy harvesting
  • Magnet
  • Piezoelectricity
  • Renewable energy
  • Tidal current
  • Wind flow


Dive into the research topics of 'An octo-generator for energy harvesting based on the piezoelectric effect'. Together they form a unique fingerprint.

Cite this