Capt. Ray Parker signaled to the deck hand to lift the vehicle ramp. With that, and a toot on the horn, the nation’s first all-electric passenger/vehicle ferry slipped its mooring in Camden, Ala., and entered the Alabama River.
The 95-by-42-foot Gee’s Bend Ferry was built in 2004 with John Deere diesel propulsion. Since 2006, the ferry has been managed and operated by Hornblower Marine Services (HMS). It can accommodate 15 vehicles and up to 132 passengers.
In 2015, HMS, Glosten naval architects and the Alabama Department of Transportation, partially funded by a grant from the U.S. Environmental Protection Agency, studied the feasibility of converting the vessel to electric propulsion. Glosten then developed the detailed design for the conversion that was undertaken by Master Marine Inc. of Bayou La Batre, Ala.
Sean Caughlan, a senior marine engineer with Glosten, said there are currently no federal regulations for vessels powered by lithium-ion batteries, which meant that designers and the Coast Guard had to establish a regulatory framework.
Capt. Ray Parker mans the helm of the ferry on an afternoon run. Recharging stations at the vessel’s two destinations provide electrical power.
“The Coast Guard was very good to work with and provided a guidance letter back in early 2016, which we used as a basis throughout the design and certification process,” he said. The collaboration continued right up until the time the converted ferry entered service in early 2019.
The ferry was gutted and all of the machinery removed to make way for the electric system supplied by American Traction Systems (ATS) of Fort Myers, Fla. The integration of all of the elements was conducted by Marine Interface of East Northport, N.Y.
“Determining the size and capacity of the batteries was a challenge that needed to balance cost, size and recharge frequency without compromising safety or straining operations,” Caughlan said. The numbers added up, and the battery banks — supplied by Spear Power Systems of Grandview, Mo. — have proven to work well with the operating and recharging schedule of the ferry.
The four Baldor electric motors with Walter gearboxes have plenty of space, compared to their two diesel predecessors, in the low engine room. Each electric motor produces 150 horsepower at 1,800 rpm. Service speed is 8 knots.
Deck hand Vondale McGraw directs commuters bound for Camden, Ala., at the Gee’s Bend dock.
The ATS propulsion rack converts AC shore power to DC power feeding two battery banks, which are located in deckhouses port and starboard. Each bank drives two motors, providing redundancy in the event of equipment failure. There are charging stations at both ferry terminals, one in Camden and the other 1.7 miles downriver in Gee’s Bend, also known as Boykin.
“This project is significant because it opens this technology up for the U.S. maritime industry,” said Tim Aguirre, general manager of HMS Ferries Alabama. “Of course not everyone was able or wanted to switch to electric cars when first introduced, and the same gradual acceptance and application should probably be expected with electric vessels as the science matures. ALDOT, HMS Ferries and the EPA are proud that we have been able to demonstrate that this technology can work on Gee’s Bend Ferry, and are excited to explore the next phase of powering the ferry from a solar-powered microgrid.”
Battery banks are located in deckhouses port and starboard on the ferry. Each bank consists of two strings of six batteries.
Four Baldor electric motors coupled to Walter gearboxes, provide a total of 600 horsepower at 1,800 rpm.
Gee’s Bend Ferry specifications
|Owner/operator: Hornblower Marine Services, Dauphin Island, Ala./Alabama Department of Transportation, Mobile, Ala.
Designer: Glosten, Seattle, Wash.
Conversion shipyard: Master Marine Inc., Bayou La Batre, Ala.
Integrator: Marine Interface, East Northport, N.Y.
Dimensions: L: 95’ B: 42’ D: 3’
Crew size: Two
• (4) Baldor IDDRPM281504 150-hp electric motors
• Walter RO-61 gearboxes, 3:1 reduction
• American Traction Systems components
• Spear Power Systems batteries