The first of the Limestone electric boats – the Aquasport 2100CC (Centre Console) model – are ready to move into serial production after the successful completion of a series of rigorous real-world open water tests using the E-Motion electric outboard powertrain from Vision Marine Technologies. (Video of the sea trial is at the bottom of this article)
The company anticipates taking orders from dealers in fall of this year and has arranged for 25 E-Motion engines, rigging components and integrated battery systems to establish a production framework.
First serial production units are scheduled for delivery in spring 2023.
“The successful sea trial results were the culmination of our team’s and partner’s collective efforts,” said Telfer Hanson, Chairman and Director of the Limestone Boat Company, who manufacture the Aquasport, Limestone and Boca Bay brands. “We are delighted with the Aquasport EV Prototype’s performance and have received significant interest from potential industry partners who share our EV vision.”
Fully electric 21 foot Center Console boat
Scott Hanson, CEO of Limestone, said “The results confirm that we can be the first to offer a fully electric-powered 21-foot Center Console boat that is expected to deliver an average cruising speed of 23 mph, over two hours of run time, and can be recharged at dockside in four to eight hours depending on whether one opts for one or two onboard chargers.”
The partnership between Limestone and Vision Marine was announced last May, then in September the first two test models for EV-integration were shipped and this May saw the start of the sea trials on the all-electric Aquasport 2100CC.
The challenge for an electric powertrain in a big water boat like the Aquasport is delivering the operating times, cruising speeds, and cycle times coastal and inland boaters want.
35kW battery packs, onboard charger
Limestone said the Vision Marine set up “met the Company’s demands and then some. It provides all of the benefits of an EV boating experience without compromising the performance expectations of an internal combustion engine and maintaining the ride characteristics for which Limestone’s Aquasport is renowned.”
The 180 horsepower (≈135 kW) E-Motion electric outboard system is coupled with two high-voltage 35kWh battery packs and includes an onboard charging system and digital screens. The sea trials on the Aquasport 2100CC delivered:
- top speed of 38 mph (61 km/h)
- planes at 18 – 22 mph (28 – 35 km/h)
- full recharge dockside in 4 – 8 hours (time dependent on use of 1 or 2 chargers)
- operating time estimated in excess of 2 hours at an average speed of 22 mph (28 km/h)
The company adds that “6 to 8 hours on the water would not be out of the question at idle speeds”.
Limestone electric boats mandate as early mover
Limestone gave itself a mandate to establish a disruptive early mover electric footprint in the traditional boating sector and says the partnership with Vision Marine provides them with a key technological advantage.
“Their E-Motion powertrain offers unprecedented power and torque in an electric outboard,” says Hanson “and will establish Limestone as a leader in the rapidly growing electric segment of the recreational boating industry.”
One of the important testing protocols focussed on safety and Limestone reports that the electric powertrain met all of its benchmarks, which are above and beyond industry compliance standards.
For the future, the companies plan to review all of the trial data to optimize performance further through things like battery placement and variable engine locations. Part of optimization may include a lighter, stronger hull laminate as the basis for an all-new electric specific version of the Aquasport 2100CC.
They are also mapping out a timeline to test the electric potential for other models, such as their Aquasport 2100 Deck Boat, a segment that has been growing both for ownership and boat rental markets.
Hanson sums it up by saying that “We’re excited about working with our EV engine partner in the months ahead to offer a fully integrated, leading-edge electric propulsion system for those seeking an alternative without having to curtail their boating lifestyle unduly”.