United States: MetalCraft Marine has delivered 'Patrol Boat-1' the first, the first ever electric powered patrol boat, designed and built for the City of Annapolis's harbourmaster.
The boat utilizes a Steyr hybrid diesel/electric engine that permits either electric power or for higher speeds, diesel power. The propulsion is a Hamilton 274 waterjet. The jet can propel the boat in electric patrol mode at 4.5 knots. To get to other areas of the expansive harbour, the diesel propels the boat to 30 knots and recharges the batteries. The design challenge was how to provide enough battery power to meet the boat's operational profile in a boat so small – 7.0 metres in length by 2.4 metres across the beam. The boat can perform its daily routine of approximately five hours on battery and two hours on diesel.
MetalCraft designed the 48-volt battery pack, with a high-output solar-assist panel array, around batteries that were commercial off-the-shelf batteries. This would allow Annapolis to easily change out the batteries as they aged. The batteries have a 4-6-year life expectancy. The total cost of the eight batteries was US$2,600.00, while the estimated fuel savings are US$550.00 per month. The reduction in overall engine maintenance is also significant, including a major reduction in oil changes from 24 to 7.2 changes per year. The speed penalty for the added weight of the batteries and electric power system is approximately four knots in high speed diesel mode.
