Longest time/distance you've had to motor?

[Cat White House]

Motor-sailed 4-5 days on one engine at 2300 rpm in a Lagoon 500 75HP Turbo Diesel on less than 150 gallons. Decent speed on one engine.

[nimblemotors]

Originally Posted by 44'cruisingcat

You can run a motor in a boat at it's optimum RPM, without going through the diesel-genset-electric motor route. It's just a matter of getting the propellor right.

Hybrids work on cars because cars have to operate at a huge variety of speeds. They also typicaly spend large amounts of time idling and going nowhere. Boats generally run at constant speed, and rarely get caught in traffic jams.

Indeed, a hybrid car has numerous advantages, but doesn't mean it has no advantages in a boat also.
In rough seas, there is not a constant load on the engine.
Or when docking in a crowded harbor.
There can sometimes be a traffic jam at the fuel dock.

How are you going to use electricity to power a boat with a diesel engine that has direct propeller drive? Or use the propeller to generate electricity?

btw, my Prius gets 55mpg on the highway at constant speed.

[nimblemotors]

Originally Posted by deckofficer

JackB,

You and I speak the same language. I have 3 EVs, an electric kayak with LiFePO4 cells for a 80 nm range, and have followed all the electric offerings.

10 KW of solar, crossed the Atlantic at 5.5 kt.
transatlantic21: The world's first crossing of the Atlantic on a solar boat

8 KW of solar, 6000 nm cruising Europe
Boat - SolarWave

6 KW of solar, can manage 3.9 kt for 24 hours on 5.5 hours of sun.
Island Pilot DSe Home Page

Cool! thanks for those links, have not seen them before.
The big solar panel roofs are not what I'd call attractive, but are effective.

[deckofficer]

Originally Posted by nimblemotors

Cool! thanks for those links, have not seen them before.
The big solar panel roofs are not what I'd call attractive, but are effective.

Attractive is not spending $15K for a suit of sails every 5~7 years.

The 10 KW Atlantic 21 was donated
The 8 KW Solar Wave is for sale $519,880 USD
The 6 KW Dse is for sale for $399,000 USD

[ArtM]

Originally Posted by nimblemotors

A yacht system could be big and bulky and inefficient, but must be cheap and have high energy density

These are mutually exclusive qualities in the current storage fields.

High-density batteries are expensive and complicated, low-density batteries are cheap and simple.

The word "density" specifically applies to the weight and size of the batteries (relative to their storage capacity), so "high density" batteries cannot be bulky or inefficient - it defies the definition of "high density"

Big, bulky, cheap, and inefficient is widely available though!

[nimblemotors]

Originally Posted by ArtM

These are mutually exclusive qualities in the current storage fields.

High-density batteries are expensive and complicated, low-density batteries are cheap and simple.

The word "density" specifically applies to the weight and size of the batteries (relative to their storage capacity), so "high density" batteries cannot be bulky or inefficient - it defies the definition of "high density"

Big, bulky, cheap, and inefficient is widely available though!

The SYSTEM can be big bulky and inefficient, but the STORAGE needs to be dense. Diesel engines are big bulky and inefficient, but the fuel is dense.
Solar panels are big bulky and inefficient too, which is OK if the energy storage was dense.

JackB

[harmonytek]

Just thinking outside the box.

A purpose built "hollow" keel filled with batteries acting as ballast would allow for a large storage capacity without the penalty of additional weight. If the keel was a bolt on type the batteries could be serviced when the boat is hauled.

These keels could be used on new boats or swapped as retrofits for older boats with bolt on keels.

Then the electric drive, with reverse propeller recharging under sail and a back up genset or solar or wind might really be practical.

[mbianka]

There is a fellow right now doing sea trials with a uniquely modified sailboat he has been working on for a few years.:
THE BIANKA LOG BLOG: ANOTHER ELECTRIC BOAT: The Archimedes Project

[Tear Away]

1600 NM 13 days just could not be buggered waiting for a wind that mite come

[Exile]

Originally Posted by Tear Away

1600 NM 13 days just could not be buggered waiting for a wind that mite come

Sounds like you must have had huge fuel capacity!

[Richard5]

Originally Posted by roverhi

36 hours powering back to SF from 180 miles west. Auxillary rudder self steering lost one of two bolts bolting it on, on the way to Hawaii. Vane rotated tearing itself out of the stern. Left a narrow strip of fiberglass holding the backstay. Set a triple reefed main to help stabilize the mast and powered in light air all the way back. Did a quick and dirty repair on the transom, reattached the vane, and made Hilo in 15 days.

Powered for about 24 hours to get through the Doldrums on the way to the Marquesas. Tried for two days to sail through it. Gave me new perspective on Coleridge's 'Rhyne of the Ancient Mariner. 100 degree temp/100% humidity, 10' swells from a storm in the Southern Ocean and ZERO wind to stabilize the boat let alone sail. After seeing my wife eyeing her carving knife longingly, decided to bite the bullet and power. Guess I consider a decent powering range as a life extending necessity.

RE: the 1st half of your post. That is a remarkable story. I can picture it. I can imagine the stress on several fronts.

[barnakiel]

Outer Hebrides to the mainland (some 100 Nm).

Last day to Tahiti (over 60 Nm)

Panama Canal (about 50Nm, I think).

There were also some stretches where we pushed along the SE coast of RSA - we motored unless sailing turned out the faster option.

b.

[Tear Away]

Originally Posted by Exile

Sounds like you must have had huge fuel capacity!

No only a small single 20hp yanmar with retractable sail drive leg original fuel tank 100ltr I added few corrlazible tanks carry five hundred and a bit ltrs now plus jerry cans I try have sail up if there's a breeze of any sort to take strain off the engine.even just a few knot wind helps.
I had to stop into a island to refuel near the end of the leg.

[barnakiel]

Originally Posted by Tear Away

1600 NM 13 days just could not be buggered waiting for a wind that mite come

WHERE

b.

[Tear Away]

Originally Posted by barnakiel

WHERE

b.

Darwin to Philippines