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Electric Propulsion tractor pull challenge....

SolidNav

Electric Propulsion
Ok...I normally leave all the forums alone but I keep reading ridiculous but forceful rants about comparing horsepower in engines to electric motors. Horsepower is simply meaningless to actual useful power. 33,000ft-lbs./minute applied to a prop (a single horsepower) would tend to create flight before propulsion in the water. Think about how much force 200ft -lbs. is if you grab a torque wrench and tighten a large nut, is it really that hard to move your boat?


So why in the heck am I posting on an Ericson forum? Quite a number of Ericson owners are customers, these boats are very similar to each other and well constructed (I sold my 27 this winter btw) and fairly consistent....so the challenge. I would like one of our customers to help me find a boat out of the same mold as their own, with a decent Atomic-4 or Yanmar 2gm20 and have an old fashioned tractor pull. Electric V Deisel, We would like to invite some of the media folks out, like we have before, www.solidnav.com/media and shoot a video to shush some folks for a bit.

A bit of showmanship in the matter could be fun, perhaps a ribbon tied between two docks (the electric will win btw). As always, we appreciate the patronage and support of the Ericson community. Let us know if we can help you as well.

Best,

Jason

Ps. Did anyone grab that 35 for sale in San Diego earlier this year? I really liked that boat, it was light blue and sold for $5,000. If you did please tell me it is awful shape so I don't feel bad about letting it get by.
 

rwthomas1

Sustaining Partner
While I really appreciate the progress in electric propulsion systems in virtually all areas, the Achilles heel of every setup is the battery technology. And the cost. The old diesel in my E38 will give me about a 40 mile range at 5.5-6kts. The nearest all-electric system would deliver about 25% of that and then require a very long recharge time. The diesel can be refueled in 15 minutes.

I'm no stranger to electric power setups, but much smaller. I fly electric model aircraft and the newest technology, brushless motors, lithium polymer batteries, etc. deliver fantastic performance comparable to IC engines with few downsides.

Lead/acid batteries do not have the energy density needed for electric propulsion to go mainstream. Lithium ion and lithium polymer are far, far better. They weigh 50% or more less, have 3-5 times the energy density, charge faster, much faster in the case of lithium ion, have virtually no self discharge, etc. There are a few downfalls, the cost is staggering, and lithium polymer has a tendency to self-ignite and burn at several thousand degrees. I charge mine in a fire safe.

I wanted to build an electric car and I looked into it seriously. I like to build stuff and it looked like a good project. That is until I did the math. $10K in parts alone, 60 mile range, and still needed the donor car. A used Civic and spending the rest of the coin on fuel would make a lot more financial sense.

Don't get me wrong, I would love to see your "tractor pull" I know the electric will win also. I've seen the electric drag race motorcycle and cars outperform IC vehicles and its stunning. For the person who primarily day sails and lives on a dock the electric setup is appealing. For me however, with the boat on a mooring, motoring for hours sometimes, then anchoring, then motoring for hours again, etc. the electric would seem to come up short. Given the cost of a good diesel engine and the relatively "cheap" fuel, my current use, I would be hard pressed to re-power with electric.

Keep working on it however, I will be watching with interest. Maybe A123 or those Chinese lithium polymer makers will get it together and start cranking out cheaper batteries.

RT
 

SolidNav

Electric Propulsion
While I really appreciate the progress in electric propulsion systems in virtually all areas, the Achilles heel of every setup is the battery technology. And the cost. The old diesel in my E38 will give me about a 40 mile range at 5.5-6kts. The nearest all-electric system would deliver about 25% of that and then require a very long recharge time. The diesel can be refueled in 15 minutes. RT

Bingo! I found this exact same problem! When I became involved in Electric propulsion I wanted to repair my Ranger 37....I was quoted 30k for parts on a 1973 vessel. This was abhorrent. You can repower a vessel, including all parts and batteries for under $7k with our systems, a price not touchable by a diesel installation. If electric propulsion will do well, it will do well because it is less expensive. Furthermore, we will be announcing terms for financing our units soon, for some reason marine items seem to be the only things that you must pay up front for in their price range, we think it would be nice to open up markets to more people.

I'm no stranger to electric power setups, but much smaller. I fly electric model aircraft and the newest technology, brushless motors, lithium polymer batteries, etc. deliver fantastic performance comparable to IC engines with few downsides. RT

I love flying in gerneal, those little planes are the precursor of actual electric aircraft. Their is one or two being made and I know of an ultralight company that builds electric aircraft now, I beleive it was called something like Vector, very cool stuff.


Lead/acid batteries do not have the energy density needed for electric propulsion to go mainstream. Lithium ion and lithium polymer are far, far better. They weigh 50% or more less, have 3-5 times the energy density, charge faster, much faster in the case of lithium ion, have virtually no self discharge, etc. There are a few downfalls, the cost is staggering, and lithium polymer has a tendency to self-ignite and burn at several thousand degrees. I charge mine in a fire safe. RT

We can get 100 miles at 4knts on 33' vessels using existing well-tested technology. The Odyssey and Northstar batteries are excellent choices for this application. They are really just fancy AGM's that are high quality lead with dry chemicals and lots of plate area. We will not support any lithium based technology as lithium is only going to get more expensive and blowing up is embarrasing, we will leave blowing up to my great boat fear, propane ;) Have you seen the damage L-ion has done in headlamps? There was a very nasty couple of test cases that I have read about.

Some exotic battery technology is out there but we have not yet seen anyhting that will safely and cost effectively store the energy. I am sure that it will come up but it for now, we stick with 20yr old technology.

I wanted to build an electric car and I looked into it seriously. I like to build stuff and it looked like a good project. That is until I did the math. $10K in parts alone, 60 mile range, and still needed the donor car. A used Civic and spending the rest of the coin on fuel would make a lot more financial sense. RT

I have systems designed as drop in for cars but that market is to large to get involved in at this time and they require a lot more energy than sailboats to move. The civic would be better suited with diesel, 40% more range right of the bat. Not the perfect solution, but turbo diesel can be clean and much much more effecient. Any deisel guys start retro fitting cars like the metro and civic let me know, I will take one.

Don't get me wrong, I would love to see your "tractor pull" I know the electric will win also. I've seen the electric drag race motorcycle and cars outperform IC vehicles and its stunning. For the person who primarily day sails and lives on a dock the electric setup is appealing. For me however, with the boat on a mooring, motoring for hours sometimes, then anchoring, then motoring for hours again, etc. the electric would seem to come up short. Given the cost of a good diesel engine and the relatively "cheap" fuel, my current use, I would be hard pressed to re-power with electric.RT

Yes, the big trick to electric has always been the frightening torque. It is quiet and small so people often underestimate the power. About once a month someone will try to arm wrestle on of our demo's and to grab the spinning shaft, this is not wise.

As far as motoring that much, ya, electric may not be the best option for you. I have sailed far and wide in the San Juan and Gulf isalnds, which are supposed to be motorign ground sof useless sailing, but I found I never motored over four hours while being out for motnhs at a time, it is a matter of how each persoopn uses their boat and where. Fortuntaley, the vast majority of sailors have their needs easily met with electric propulsion. Our best cients really come in two forms, the offshore sailor who spends a lot of time on crossings where the motor acts as a generator while under sail and the customer who sails one week a year, every weekend during the summer and one race a week.

Keep working on it however, I will be watching with interest. Maybe A123 or those Chinese lithium polymer makers will get it together and start cranking out cheaper batteries. RT


Thank you so much for taking the time to look intour product. We are following the development of this sit with interest as well. This site could sell web design to other owner sites, very nicely executed.

Best,

Jason L. Russell
 

paul culver

Member III
SolidNav, while you're here can you answer a question for me? What are the details of the motor's regenerative capabilities under sail in neutral? Say in the 4 to 5 knot range? I haven't found any such info on your site.

Thanks

Paul
E29 "Bear"
 

SolidNav

Electric Propulsion
SolidNav, while you're here can you answer a question for me? What are the details of the motor's regenerative capabilities under sail in neutral? Say in the 4 to 5 knot range? I haven't found any such info on your site.

Thanks

Paul
E29 "Bear"


Sure Paul,

You can achieve anywhere from 200w to 400w. There is a degree of "black art" in the matter due to the state of charge of the batteries and due to the differences of water pushing over the propeller. The first 80% of charge should occur quickly and the reminder takes quite a bit of speed to overcome the bank voltage. Think of it like tubs of water. the speed slows greatly when they are almost equal. Be careful to measure both volts and amps to get watts under recharging. It requires some tinkering for everyboat.

One of the great beauties of electric power is that you have options to repower. When using diesel, you can only fill with diesel, when using electric, you can use wind, solar, tow drogues, very very efficient dock power, regeneration under sail and even diesel or gas in small genset to power your motoring. YOu are not locked into one particular source with electric, I am sure people will devise even more creative and unique methods in the future.

Best,

Jason
 

steven

Sustaining Member
SolidNav,

I have an A4. Been hoping the electric technology would mature before it needs to be replaced.

Re: "... 100 miles at 4knts on 33' vessels..." What battery weight does it take to get that. How about for speed closer to hull speed, say 6knts?

Thanks

--Steve
 

Mark F

Contributing Partner
Blogs Author
Steven,

I have two sets of four 12 volt batteries in my E27 - about 560#. So far the longest I have motored is just over 7 hrs at 4 knots (20 amp draw) and didn't use all of one set. To motor at hull speed you're going to use up your batteries pretty quickly. I pull somewhere around 120 amps to go 5.8 knots.

Jason,

It seems a longer waterline will motor faster than a shorter one. Is that true?
 

Glyn Judson

Moderator
Moderator
Battery range increases.

All, Apparently there is a new technology in batteries developed in Liechtenstein that for the first time equals and betters the performance and range when compared to internal combustion engines with normal tankage and is particularly suited to marine applications. Transoceanic passages are being predicted on one charge. The breakthrough comes in the form of a new material used in their construction. Advanced word is that although very rare and pricey at the present, it promises to be the wave of the future given the recent discovery of this mined material. Some of you may already have heard of it, the material is being called Unobtanium. So be on the lookout for Unobtainium cells to start making headlines the world over. Bye, bye diesel and A4's. Hope this brightens your day, Glyn
 

rwthomas1

Sustaining Partner
Glyn, thanks for making me laugh!

My issue with any new idea is that it is sold, even in the posts above, as THE solution to your problems. There are lots of great ideas but at least please be very honest about the drawbacks.

-I've yet to see data that supports an electric propulsion system that would work on my E38 for anything other than daysailing from a dock.

-Full of fuel, 40 gallons is about 250lbs, the auxiliary is approx. 350lbs for a total of 600lbs. Then I see batteries on the electric E27 weigh 560lbs. Pretty sure the system for my boat would be double that.

-I am unwilling to motor ANYWHERE at 4kts. I light off the diesel if I can't sail at 3kts and if I can't make at least 5kts under power then whats the point? 7 hours at 4kts or 3.5 at 6kts, I'd be in the harbor safe and on my 4th drink by then.

-Unless you have dock power and are willing to wait to recharge its no good. Couple that with the fact that batteries don't really like to live long lives in a partially discharged state, you basically have no choice, unless you enjoy paying for a pretty expensive propulsion bank every few years. It's going to take a good long while to top off a bank like what I would need for the E38 from solar panels, wind, etc.

-I have no interest in towing a bucket OR a rotating prop that knocks my SOG down. Losing 1kt per hour can make the difference in getting to the anchorage before dark or getting there early enough to score a mooring.

Now if the prices that SolidNav is quoting on their website INCLUDE the batteries, then it is indeed quite competitive. I think the original response to my post of a $30K diesel re-power is a just a bit high. Last time I checked most diesel re-powers run $10K-$15K on 30-40ft boats?

I wish SolidNav, and any other purveyor of this technology the best, I really do. I just want them to understand that you are not going to sell a skeptic like me on the positives. I already understand them. You need to address and mitigate the negatives instead. IMHO, the battery technology is not good enough yet. When lithium polymer becomes understood and accepted then maybe. RT

Oh yeah, this week at Oshkosh a new experimental ELECTRIC light plane was on display. We may yet be on the brink of the breakthrough. Lithium polymer of course....
 
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SolidNav

Electric Propulsion
Why we leave forums alone

Now wait a second,
Pardon me for taking a touch of offense, but slamming my product without empirical evidence is really inappropriate. If you want to motor at full speed across an ocean, my product is simply not for you, neither is a sailboat. I did not advertise nor would I, my product on this forum. I am happy to answer questions to legitimate customers, or potential customers and will offer empirical facts, if you like the performance of our system, great, if not, don't buy it. I prefer if clients and customers contact me offline for answers, rather than I am not here to argue with someone who may not be a great client for electric, though many folks are.

Again, If you want to motor for at 4knts for 100 miles, awesome, very little motor-sailing actually will extend your speed a lot. If you want to run at hull speed across the Pacific, I have a friend who sells Nordhavens and Grand Banks and it is a super time to buy. I asked a question of some of my existing clients, the majority of Ericson owners actually sail a lot (a trait found with owners of boats that actaully sail well), have aging motors and have installed quite a few of our systems. It makes sense to control variables or information with consistent built and designed hulls. So pardon me if I do not head down item for item and just address the facts.
 

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
Ahem, a moment, please

Um, hello, how about a nice cup of Chamomile Tea.
;)
I have learned some new information from this thread, and would agree that different forms of aux. propulsion are best suited for quite different purposes.

Within the limitations of each technology, let's focus on the advantages...
and there are some.

After all, the early internal combustions engines were a far cry from the modern ones that (mostly) work so reliably for thousands of hours, and put out so many HP for such little weight.
I was just mentally picturing the hundred-year-old one-lungers in the working displays at a local museum, Antique Power Land,
http://www.antiquepowerland.com/
and of course the static displays the renowned maritime museum at Astoria, OR.
http://www.crmm.org/

The evolution of battery technology and electric motor power will likely continue apace.... one can only hope. After all, it's only been about a year since an electric aircraft flew at the big show at EAA Airventure Oshkosh. I bet that a plane-load of people never thought they would see such a thing. :nerd:

So everyone please step back from their key boards for a moment and imagine a sunny reach on a 12 kt day...
:egrin:

Cheers,
Loren
 
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ted_reshetiloff

Contributing Partner
Solidnav I think you missed the point of RT's post. He was not slamming your product. He was simply stating that it was not a comparable replacement for the existing diesel in his 38. The system may be just fine for a 27' boat and its requirements, but unless I missed something it did not sound too practical for the 38. When an electric repower can match or beat a diesel repower on all of these:


Range: 400 miles on a tank
Refueling time: 10 minutes
Speed: 6kts
Weight: 600lbs
Cost: $15k

Until an eletric repower can do this diesel repower makes the most sense. These are not unreasonable requirements for a 38 foot boat.
 

SolidNav

Electric Propulsion
Um, hello, how about a nice cup of Chamomile Tea.
;)
I have learned some new information from this thread, and would agree that different forms of aux. propulsion are best suited for quite different purposes.

Within the limitations of each technology, let's focus on the advantages...
and there are some.

After all, the early internal combustions engines were a far cry from the modern ones that (mostly) work so reliably for thousands of hours, and put out so many HP for such little weight.
I was just mentally picturing the hundred-year-old one-lungers in the working displays at a local museum, Antique Power Land, and of course the static displays the renowned maritime museum at Astoria, OR.

The evolution of battery technology and electric motor power will likely continue apace.... one can only hope. After all, it's only been about a year since an electric aircraft flew at the big show at EAA Airventure Oshkosh. I bet that a plane-load of people never thought they would see such a thing. :nerd:

So everyone please step back from their key boards for a moment and imagine a sunny reach on a 12 kt day...
:egrin:

Cheers,
Loren

Loren,

I hope that was an offer, I happen to be in Astoria today and I do like tea and the PNW coast ;) The museums are second to none. The history of electric boats dates back to the Post civil war era, I actually saw Eisenhower's first car, an electric, at his library and memorial in Kansas. You are very correct about the ancient systems, our product has and will continue to evolve for perpetually. I wonder what we would have if we continued to develop cars at the same rate we have previously developed motors.

Any takers on my original challenge?
 

rwthomas1

Sustaining Partner
Solidnav I think you missed the point of RT's post. He was not slamming your product. He was simply stating that it was not a comparable replacement for the existing diesel in his 38. The system may be just fine for a 27' boat and its requirements, but unless I missed something it did not sound too practical for the 38. When an electric repower can match or beat a diesel repower on all of these:


Range: 400 miles on a tank
Refueling time: 10 minutes
Speed: 6kts
Weight: 600lbs
Cost: $15k

Until an eletric repower can do this diesel repower makes the most sense. These are not unreasonable requirements for a 38 foot boat.

Thanks Ted.

IMHO, there are still too many compromises with the current electric setups, GIVEN MY BOAT and MY use. I can name ten or so sources for diesel repowers that are completely proven and would improve the performance of my boat, should it need a repower. I cannot say that about electric propulsion. Yet. Best of luck to the pioneers of electric technology. I know that the technology will be comparable to IC in the near future and then I may consider it.

RT
 
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