by John Sharp
The UK division of the ePropulsion has just signed a deal to supply 60 fully-integrated propulsion systems to RS Sailing, for the latest RS 21 keelboat.
The new supply contract covers a bespoke mounting arrangement and integration of ePropulsion’s 1KW ‘Spirit’ electric motor into a flush-fitting retractable electric drive system onboard the first 60 boats in RS Sailing’s fleet of exciting new RS21 keelboat day racers.
“The main challenge was to create a brand-new plug-n-play system for one of the fastest-growing classes of keelboat in the world,” explains Ricky Cole, head of technical development at ePropulsion UK. “Short lead times are standard for new racing classes, but we also had to create an out-of-the-box solution that can be used during the boatbuilding process, or sent for retrofitting on boats anywhere in the world that is already being raced.”
“The system has been engineered from marine-grade materials to give years of trouble-free service,” added Cole. Starting at the top, ePropulsion UK re-designed the top bracket motor mount which is CNC machined from solid 6061 aluminum alloy with a hard-anodized coating. A proximity switch has also been added which only allows the motor to run when it is locked down in the correct operating position.
Due to the length of the cables and the large current draw, the system has been designed with the highest quality cable and connectors which will maximize the efficiency and longevity of the solution.
To create a seamless plug-n-play propulsion system, ePropulsion has also designed a new side-mounted throttle arrangement with a removable handle which will really help to reduce snags in the racing cockpit. All of the battery and motor information is displayed on a new high-contrast LCD screen which is easy to read even in direct sunlight.
The last part of the solution is a new nylon mounting bracket with stainless steel fittings that mates the skeg of the ePropulsion motor to the outer hull plate. When racing, the whole motor arrangement, which only weighs 7kg, is hauled-up into the stowed position with the outer hull plate flush with the rest of the hull, eliminating any unnecessary drag.
“You can usually expect some teething issues with new boat designs but the ePropulsion solution has been seamless,” says Alex Southon, RS Sailing’s CEO – Design and Technologies. “Their system works perfectly and is one of the easiest systems we fit on the boat, even when we are retrofitting on boats away from the factory. It’s silent, robust and really complements the overall quality of the RS21 package.”
The 1KW Spirit propulsion motor provides the equivalent thrust of a 3hp petrol outboard, without any of the downsides of combustion engine ownership. There’s no fuel or oil to spill, no regular servicing, no tricky starting procedure, and noise or fumes when operating, just smooth, silent thrust that’s available all the way through the rev range.
There’s also no need to swivel the motor around for reverse thrust, just push the throttle lever forward to go forward and pull it back to go backward, this intuitive system really helps when maneuvering the RS21 back to its berth.
*The performance data of RS 21 was collected in a test ride with two sailors on board. It’s for reference only and the actual performance may vary due to the sea state, load, and other conditions.