| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 300201 | Renewable Energy | 2014 | 9 Pages |
•Assessment of tidal current potential was carried out at a location in Fiji.•A horizontal axis tidal current turbine is designed for a current speed of 1.5 m/s.•Five hydrofoils with different thicknesses were chosen for the blade from hub to tip.•A 3-bladed 5 m diameter rotor was designed for this location.•The turbine has a maximum efficiency of 47% at the rated velocity.
Pacific Island Countries (PICs) have a huge potential for renewable energy to cater for their energy needs. Marine current energy is a reliable and clean energy source. Many marine current streams are available in Fiji's waters and large amount of marine current energy can be extracted using turbines. Horizontal axis marine current turbine (HAMCT) can be used to extract marine current energy to electrical energy for commercial use. For designing a HAMCT, marine current resource assessment needs to done. A potential site was identified and resource assessment was done for 3 months. The coordinates for the location are 18°12′1.78″S and 177°38′58.21″E; this location is called Gun-barrel passage. The average depth is 17.5 m and the width is nearly 20 m – the distance from land to the location is about 500 m. A multi cell aquadopp current profiler (ADCP) was deployed at the site to record marine currents. Strong marine currents are recorded at this location, as a combination of both tidal and rip currents. The maximum current velocity exceeds 2.5 m/s, for days with large waves. The average velocity was 0.85 m/s and power density for the site was 525 W/m2. This site has good potential for marine current and HAMCT can be installed to extract power. A turbine with diameter between 5 and 8 m would be suitable for this site. Therefore, a 5 m HAMCT is designed for this location. The HF10XX hydrofoils were used from blade root (r/R = 0.2) to tip (r/R = 1.0). HF10XX series hydrofoil sections were designed to operate at varying turbine operating conditions; these hydrofoils have good hydrodynamic characteristics at the operating Reynolds number. The turbine is designed to operate at rated marine current speed of 1.5 m/s, cut in speed of 0.5 m/s and cut off speed of 3 m/s at a tip speed ratio (TSR) of 4.2.
