Electric Sail-drive - New Alerion Express 33 silent, pretty and green

Alerion Express 33 sailing SW

Alerion Express 33 interior © SW

The application of this technologically advanced propulsion system in the Alerion Express 33 was spurred by a customer who did not want to spoil the quietness of the intimate, nature-filled waters he prefers for sailing near his home in Vancouver, Canada. His query whether the diesel saildrive, which is standard in this model of Alerion, could be replaced with electric propulsion resulted in this launching.

Mastervolt, a Dutch specialist in marine electrical power, had been investigating the potential of Lithium-Ion batteries for marine use. These batteries, which in smaller sizes power mobile phones and laptop computers, are highly desirable for their compact size, light weight, low rate of self-discharge and lack of 'memory effect.'

After extensive R&D, Mastervolt had developed a high-capacity Li-Ion battery, tailored for marine use, that is 15% more efficient and saves up to 70% of space and weight, compared to typical lead-acid boat batteries.

The Alerion Express 33 was an ideal 'platform' for Mastervolt's system for several reasons. Alerion Express sailors choose these boats for their 'pure' sailing experience: perfect for responsive, sensitive performance under sail, not intended for long voyages but for frequent daysails where even an hour's voyage is a welcome break in a busy day, and a closeness to nature that only a silent, gliding sailboat can optimally deliver.

Alerion batteries © SW

Mated with Mastervolt's 7.5 kW saildrive system, their MLI 24/160 Li-Ion battery on a single charge gives the Alerion Express approximately 15-20 nautical mile range - which can be greater or less depending on speed, number of crew, wind and weather conditions. Installing additional MLI 24/160 packs, which are relatively small and lightweight, permits those who might face longer motoring situations to still use this system.

The experience of motoring the Alerion Express 33 has been described as 'Astonishing' by boat reviewers, dealers and sailors of all stripes. Underway, even at full speed, the only noise on board is the rustle of wind, the slap of crossing another boat's wake or crew conversations.

Said one reviewer, 'I didn't realize we were under power until I noticed our wake and saw moored boats passing us! It took time to adjust my behavior, throttling back when underway - because there is no spooling up noise of a diesel.' A marine electronics writer, measuring dB readings on deck and below with a sophisticated sound meter, could detect no motor noise.

Alerion Express 33 sailplan © SW

Maneuvering, especially in docking or leaving a slip, is made easier because, with electric motors, full torque is available the moment the motor is put in gear. So, acceleration and stopping power are noticeably stronger than with conventional power. Yet, the most noted attribute is the silent operation. One experienced sailor remarked, 'I just wasn't prepared for how this affected me. It made me realize how noisy all my boats have been, and how far that is from what I love about sailing. Now, I won't be content until I have one of these.'

Pearson Composites, builder of Alerion Express sailboats, pursued this project as a natural extension of efforts through the years to improve the environmental 'greenness' of their products. The company pioneered the use of the patented SCRIMP process, whose closed-system infusion makes the most efficient use of materials and eliminates the release of volatile organic compounds (VOCs) into the air during manufacturing. The company was also one of the first builders of windmill blades for generating electricity.

For more information about the electric-drive Alerion go to www.alerionexp.com.

Alerion Express 33 layouts © SW