Jimmy Cornell goes Electric, with a Cat

[sailingharry]

Originally Posted by CatNewBee

This discussion is ridiculous, we are talking about replacing a tiny toy 40..50hp efficient diesel engine, that limps us home in unfavorable weather or is used for docking - by an expensive electric drive or hybrid. But forgetting the small tripper boats with 3 to 4 x 250hp gas outboard engines, or the real deal power boats with several 1000hp, that go to the fuel dock after a joy ride for a day and refill 4000$ worth of diesel. Who cares if a sailing cat burns 200 or 300l per year really, when the charterers burn it on a daily basis?

This!


The news and other sources talk about unplugging your cell phone charger after the phone is charged, since it burns .000001 W when not running.


Until we as a nation find a way to effectively stop (by directly outlawing, or making it massively less affordable) the mega-yachts and the super-go fasts (as well as the Yukon SUVs, the McMansions cooled to 65F in south FL, pleasure airplanes, etc, etc, etc) -- in other words, until we are willing as a nation to take the painful impact to our personal lives and the economy (remember, the mega-yachts fuel more of the "marine-economy" than all us regular folk combined!), we really are kidding ourselves.


Sure, eliminating my 300 gallon annual consumption is something. But at my last fuel stop, as I put 90 gallons in my boat, the Flemming 50-something behind me who had just finished the same trip to Maine was preparing to take on 1,000 gallons -- and I'm sure that wasn't his only fill up this summer.

[JustMurph]

I suppose the real driver is more so the comfort (no noise from motors or generators) and convenience of needing less fuel and mostly being energy independent. Green credentials are minimal.

[jmh2002]

Yes, all of peripheral benefits start to make an overall sum that is perhaps greater than the individual parts.

And even when needing to motor longer distances with a genset driving the electric motors, a remote mounted genset can often be much quieter than actual propulsion engines.

[seandepagnier]

Originally Posted by JustMurph

Just playing devils advocate here, the electric motors, along with the big battery bank and the big solar array is going to make your boat quite a bit heavier...
Maybe a worthy trade off though...

My motor weighs 2 pounds and the solar panels weigh 8. The battery weighs 15 pounds. It can motor non-stop if the sun is out without draining the battery. I have 33ft boat.

Originally Posted by Adelie

Dinghies have the same issues as motherships when converting to electric: range and speed. If you use enough power to get on a plane, your range will be drastically diminished.

Sailing dinghys can get on plane, but there is no reason for a dinghy to travel more than 3 knots, because they do not go very far.

Originally Posted by sailingharry

I can't agree on either point.


* The EP supporters suggest that an appropriate replacement for the 55 HP diesel (with 94 gal fuel!) on my boat is a 20HP equivalent, with enough battery to motor at 4 knots for 30 miles (or 6 knots for 5 or 10 miles). Even the most ardent supporter wouldn't recommend anything in the 3-5hp rating for a 22,000 lb 43 foot boat! However, I do see

They used to pull 60ft boats with a single horse. This comparison of "horsepower" is a misconception because

1) electric motors can do 3x their continuous rating or more in bursts
2) inboard diesels are 5-15% efficient (you need a propeller diameter at least half the beam of the vessel to achieve 90% efficiency at the prop, so most are in the 30-40% range which is pathetic) decent electric drives are > 50% efficient.

Originally Posted by JustMurph

Life's too short for motoring at 4 knots. Just sayin'.

You mean to say life is too short to motor at all.

Originally Posted by CatNewBee

This discussion is ridiculous, we are talking about replacing a tiny toy 40..50hp efficient diesel engine, that limps us home in unfavorable weather or is used for docking - by an expensive electric drive or hybrid. But forgetting the

That isn't how jimmy cornell used his motor. He just motors and motors then runs out of battery and throws up his hands when if he had been sailing...

small tripper boats with 3 to 4 x 250hp gas outboard engines, or the real deal power boats with several 1000hp, that go to the fuel dock after a joy ride for a day and refill 4000$ worth of diesel. Who cares if a sailing cat burns 200 or 300l per year really, when the charterers burn it on a daily basis?

Well. No one said we "forgot" about those ones. I have witnessed them point back at a sailboat with 2hp outboard (not my boat) and say "you are burning the same gas as my 150hp and so you are the same as me" This doesn't make any sense logically but not using fuel at all improves the position as well as the fact that 200 liters is a huge footprint well above the average human. 20 liters of vegetable oil a year would be more reasonable and cheaper.

Originally Posted by jmh2002

Even though I'm an electric enthusiast, from an overall environmental point of view, as well with consideration of today's costs and levels of technology, it's hard to argue with that.

Sailing boats don't generally burn much diesel in the first place. An an optimised sailing boat, both in terms of sailing efficiency as well as energy production, burns even less.

you mean they don't need to burn any diesel, but because the price is too cheap people do burn much diesel because it takes slightly more effort to raise the sail.

[JustMurph]

Originally Posted by seandepagnier

My motor weighs 2 pounds and the solar panels weigh 8. The battery weighs 15 pounds. It can motor non-stop if the sun is out without draining the battery. I have 33ft boat.

Not all of our boats run on unicorn pee and rainbows.
It isn't representative of the average cruisers needs.
In all seriousness, that's awesome and what it can do is impressive. You have me curious about what kind of power with a mega prop it would take to drive my 48 footer at say 4 or 5 knots.

Originally Posted by seandepagnier

Sailing dinghys can get on plane, but there is no reason for a dinghy to travel more than 3 knots, because they do not go very far.

Plenty of us use our dinghies for expeditions to go diving, windsurfing, surfing etc etc so need to be able to cover some distance at speed while carrying some weight. Electric can make sense for a lot of cruisers who just come and go from the beach and other vessels.

[Adelie]

Originally Posted by Simon.Sails

I fully agree that any comparison has to be fair, so expected distance traveled by motoring or motor-sailing has to be the same diesel/gas vs. electric.

But I suspect that your assumption that a sailboat with minimal motoring is better off with diesel than electric to be wrong. For minimal use an electric outboard/inboard with a small battery is sufficient, low maintenance and cheap and certainly greener than a (new) diesel inboard or gas outboard. Whether a conversion makes sense is another question entirely, especially as the replaced engine usually has a second life.

It’s not fair and never will be. Electric will never have the same performance as a diesel.
Electric can’t match the significant range at speed that diesel can provide.
Diesel can’t match electric’s unlimited range at slow speed without refueling.

Apple-oranges comparison, always will be.
Choosing EP is a values decision.

[jmh2002]

@JustMurph

[sailingharry]

Originally Posted by Adelie

Apple-oranges comparison, always will be.
Choosing EP is a values decision.

Exactly. And that's the challenge the EP advocates face. It will never be "you can cut your fuel consumption if you go EP." It will always be "if you replace your current desires with this alternative set, you'll be able to cut your fuel consumption." That's the important part. The EV conversion was simple, because we didn't ask the driving public to replace their 75MPH gas cars with 25 MPH electric cars -- we allowed them to have the same (or even better!) experience.


Now, if we could convince the majority of sailors to change their use-scenario, it might take off. But while I didn't like motoring as much as I did this summer, by sailing more I wouldn't have covered 2800 miles, been to 87 different locations -- and been anchor-down before dinner every night. In short, I wouldn't have done it -- taking 15 hours to go 30 miles isn't my idea of fun.


Sure, I'd be a better sailor if I learned to enjoy sailing in 3 knts of wind. I'd be a less stressed person if I could cool my heels in a harbor for 3 days waiting for ideal weather. I'd be much better for the planet if I motored at 3 kts (even on diesel -- I bet 3kts uses 20% of the fuel as 7 kts). But we bought this boat to GO PLACES. Not to sit in the Chesapeake. And I (like 95% of the boating public -- maybe even more) aren't willing to make that value choice.


I am fairly sure, however, that as my wife and I burned 300 gallons of diesel this summer, we had a lower carbon footprint than our land-bound next door neighbors (who probably burned that much gasoline, not even counting their electric bill). I'm happy being in the front of the pack -- I don't have to be the single lowest carbon footprint in the state!

[Adelie]

Originally Posted by CatNewBee

This discussion is ridiculous, we are talking about replacing a tiny toy 40..50hp efficient diesel engine, that limps us home in unfavorable weather or is used for docking - by an expensive electric drive or hybrid. But forgetting the small tripper boats with 3 to 4 x 250hp gas outboard engines, or the real deal power boats with several 1000hp, that go to the fuel dock after a joy ride for a day and refill 4000$ worth of diesel. Who cares if a sailing cat burns 200 or 300l per year really, when the charterers burn it on a daily basis?

If you think this discussion is ridiculous, then don’t participate.

[aqfishing]

Life's too short to do anything under 5 kts!

[Adelie]

Originally Posted by aqfishing

Life's too short to do anything under 5 kts!

That’s fine. But why are you participating in this thread? EP won’t give you 5kt, not for any significant range.

[aqfishing]

Originally Posted by Adelie

That’s fine. But why are you participating in this thread? EP won’t give you 5kt, not for any significant range.

Why not? (Participate)

[JustMurph]

Originally Posted by Adelie

If you think this discussion is ridiculous, then don’t participate.

Originally Posted by Adelie

That’s fine. But why are you participating in this thread? EP won’t give you 5kt, not for any significant range.

Really?

They're valid points of view.
Electric will give you 5+ knots for an extended range, with a generator, just like 99% of cruisers would specify, so that is 100% relevant.

[Simon.Sails]

Originally Posted by Adelie

It’s not fair and never will be. Electric will never have the same performance as a diesel.
Electric can’t match the significant range at speed that diesel can provide.
Diesel can’t match electric’s unlimited range at slow speed without refueling.

Apple-oranges comparison, always will be.
Choosing EP is a values decision.

I agree - but that comparison has to be made to point this fact out. As you say, electric cannot do what a diesel can, but diesels can't do what electric can.

I'll install an electric outboard on my trimaran this Winter and will report back for next season. Pretty sure I can use the motor a lot more and further than people would anticipate. But it's a very fast, light boat so that helps.

[Adelie]

Originally Posted by Simon.Sails

I agree - but that comparison has to be made to point this fact out. As you say, electric cannot do what a diesel can, but diesels can't do what electric can.

I'll install an electric outboard on my trimaran this Winter and will report back for next season. Pretty sure I can use the motor a lot more and further than people would anticipate. But it's a very fast, light boat so that helps.

You indicated comparison had to be fair and they had to have similar ranges.