- Fishing boat "RAICHO-S" -

    The university has created new type of electric boats "RAICHO-I" and "RAICHO-S" in 2010 and 2011, respectively. These crafts have some special and unique features that set it apart from existing electric boats or battery-powered boats. First, these utilize a lithium-ion battery with plug-in system or a rapid charging system. A dockside-mounted rapid charger can bring the boat's battery up to 80% of full charge within 30 minutes, which is a much faster than conventional charging systems. The boats can operate for 45 minutes at full speed and berth for 30 minutes while recharging in a cyclic operation. "RAICHO-S" utilizes a water jet propulsion system driven by electric motor whose advantages are safety for the diver, passing floating rope on fish preserve, and environmental reservation (no-damage on fishes and aquatic plants). The disadvantage of water jet driven by combustion engine in low efficiency and low maneuverability at low speed can be overcome by use of electric motor.

June 2011

May 2011

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- Specifications -
8.04 m
2.24 m
0.85 m
Motor output:
25 kW
Light load:
14 knot
Middle load:
12 knot
Heavy load:
10 knot
Navigation service:
45 minutes
Battery capacity:
18 kWh
(SOC 80%)

- Water jet propulsion -

Water jet propulsion driven by an electric motor

Advantages: Safer for divers, and when passing floating ropes in fish farms, and safer with regard to environmental preservation (no damage to plant, fish, or the ecosystem)

Disadvantages: Low efficiency and low maneuverability at low speed -- improved by use of the electric motor

water jet propulsionphoto

- Participation enterprise consortium -

The electric boat "RAICHO-S" was built by the university, with financial and technical support from the participation enterprise consortium.

  • Tosen Marine Inc.: Joint research
  • ULVAC, Inc.: Joint research
  • Ishigaki Company, Ltd.: Joint research
  • Chugoku Marine Paints, Ltd.: Technical support