Link back to my sailboat page.

I'm thinking of replacing my 28-HP Volvo Penta diesel with a low-maintenance, clean, where possible solar-powered electric motor. This is a long-term project, for now I'm just looking around trying to determine feasibility and price.

I've found a few links of interest.

• The Electric Vehicle List has good information.
• Lynch Motors makes electric motors and seems to know about boats. They also have lots of good information, such as these 12V efficiency/torque/power curves and a PDF document about electric component selection and the magic of propeller selection.
• Many electric vehicles seem to use motors from ADC Motors. One supplier appears to be Global Light and Power", though their current web page lists nothing from ADC Motors. They now appear to sell Scott Motors instead -- these are produced by Imperial Electric, but trying to follow this link crashes my browser (Netscape 4.73), maybe because they seem to want you to use shockwave flash and mine could be mis-configured. In any case, very little in the way of technical specs.
• A controller manufacturer in the UK, 4QD has a fairly good FAQ (organized alphabetically rather than by subject, but still helpful). The FAQ also points to a number of motor manufacturers.
• American Marine Electric Motors Corp has a motor that goes underwater and reportedly (in a private email) produces 300 lbs of thrust for 4.5KW (36V x 125A). They plan to be in production in September '01.
• Ray Electric Outboards claims to have invented the industry (where's Al Gore when you need him? :-). Only go here if you want to be bedazzled by unnecessary graphics. They do have an electric outboard rated at 270lbs of thrust at 5KW (60V x 84A).
• Solomon Technologies has a couple of motors that seem to be designed specifically for marine applications and sailboats -- the motors are designed to recharge the batteries when the prop freewheels. The brushless DC permanent magnet motors run at 120 to 144 Volts DC, and I believe have a transmission (an "internal" transmission -- less maintenance?). They will only sell complete installations. Caveat -- it is not clear how the motor is cooled (it seems unlikely the engine is 100% efficient -- from the pictures it appears to be aircooled). Seems good for replacement of existing diesel motors.
• Electric Launch Company. Commercial electric installations. They are located in New York state. I sent them mail and they replied suggesting an 8 HP 72 volt motor. I asked about 12V motors and got no reply.
• Beckman Boatshop Limited. Commercial electric (and steam) installations. They are located in Rhode Island.
• Electric Boat Association. Not a lot of technical information, mostly just a plug for their $35/year membership, but they do have some interesting links reached from the bottom of their home page, departments, link.
• Duffy Electric Boat Company . Interesting and motivating. I contacted them by email, and they don't do custom work.
• Black River Boats . Small boats only. Located in North Carolina. They list an Electric Boats book available from Amazon for $14.36 plus shipping.
• Jim Kerr, in New Jersey, will do custom electric boat design or conversion. He also has a great list of links to relevant suppliers. Among others, he lists: Electric Vehicles of America, Inc P.O.Box 59, Maynard, MA 01754 This is a good source for motors and controllers which can be used for larger boats.
• Unique Mobility, Inc. produces brushless, permanent magnet DC motors, both air and water-cooled, from 2 to 100 HP. They seem mostly focused on the wheelchair market, and I have not contacted them yet. They have no technical or price information on their web site.
• Having gotten a catalog from Baldor, I was in need of a good explanation about electric motors, which includes a list of motor manufacturers.
• I may consider installing outboards:
  • Ray Electric Outboard Co, Florida. Up to 270 lbs of trust, but even long shaft only accomodates 24" transom.
  • Reservoir Runner, Maryland. Model 500 (long shaft, actual length unknown) is rated at 6HP (thrust estimated at 250lbs using 5500W and a Kort nozzle ducted prop) at 60-72V, weighs 86 pounds, currently (1999) lists at about $4K. They estimate about 950W/HP at 80% efficiency. See here for details.
  • Minn Kota sells trolling motors. Their most powerful has 70lb trust at 24V and 1KW with up to a 42" shaft. Their largest 12V marine model gives 55lb trust at about 700W.
• For the occasional long range, it is possible to use fuel cells or microturbines as well as generators (which can be found both at Southwest Supply and Generator Joe, with thanks to Ken James for the links, and Don Robertson's Marine Marketplace). One manufacturer of fuel cells is HPower -- see this link (taken from the fuel cells web page) for a longer list. Regular outboards are also an option.

  One more exotic technology is presented here. Basically, it is an extremely efficient steam engine using a special cell (Caloric Porous Structure Cell, CPS Cell) to burn the fuel.

• It's unlikely but not impossible that boatscape may have electric motors for sale.
• Good battery resource from Windsun
• If I were very rich, I would consider using Electrofuel as an energy storage device. They sell Lithium Ion SuperPolymer batteries that can hold 160 Wh (11Ah at 15V) in a unit that weights 1.1Kg or 2.4lbs (currently only designed for computer laptops). See here for purchasing. The price is currently $500 -- if I wanted 2000 Ah, I would need about 180 of the units, setting me back almost $90,000 but weighing only 430 pounds (less than 3 8D batteries). Let's hope the price comes down as the technology matures.

1. Replacement for my current engine, a 28-HP Volvo 2003 diesel.
2. Quiet.
3. Efficient. I'm willing to consider replacing my prop if that would help.
4. Long-range. This is usually a tradeoff between price and weight versus range.
5. No maintenance. This means no transmission (if possible), no oil to change (if possible). I'm willing to replace batteries every few years.
6. 12V system. This would make it easier for me to use off-the-shelf stuff, including solar panels to recharge the batteries.
7. Experience. All else being equal, I prefer someone who has done a similar installation before.
8. Location. All else being equal, I prefer someone based in Hawaii or with a permanent presence in Hawaii.

1. Space. I do have a large engine room.
2. Weight. My boat weighs 15 tons already, even another ton might not make that big a difference.
3. Price. While price is always a consideration, I'm not necessarily shopping for the lowest possible price, especially if the higher-priced alternative is notably better.
4. Time. I'm not planning on doing this work until 2003.