Electric Feasibility Study for an Owens

Thanks for that Eric, I had hoped this thread would smoke you out of that hole you've been hiding in up in Concrete lately. Good to hear from you. I'm going to do some real world testing throughout this summer to get some data points on HP required. If a force gauge falls out of the sky I'll try Reuben's tow rope idea if not my Livingston is gonna get a workout seeing what the GPS will read.

I suspect it will take less HP than most would have me believe to move this old lady along at about 5-7 MPH.

Jeez! I go to sleep and awake to a plethora of posts! I am only sorry I never joined the debate club in school - it would certainly have proven of use over my lifetime. In my senior years, I tend to enjoy debate (much to my wife's consternation) and see NO subject as off limits. I love talking politics with those with ideas contrary to mine - likewise religion - and now boats! Let the conversation continue...

I don't know where to start?

Marin, you're up first: How many current cruising boats can you name that have a range of 600 nm at 13 knots? Or, better yet, how many boaters go 600 miles between stops? When is the last time you shopped new boats? One of the current best selling cruisers are those from Ranger Tugs - they have nailed it - a semi-displacement, trailable cruiser for around $200k for a bit shorter than 30' that sleeps 2 OK and 2 in the basement. Not at all efficient fuel-wise compared to other offerings of similar size, but at displacement speeds, as good as any. It is now possible to build a similar-sized e-boat for a similar price - main difference is it will have DIFFERENT PERFORMANCE, not necessarily less, just different. Slower? Yes. More spartan? Not really. Less range? No. Less range at a single leap? Yes. But total range is essentially infinite. So, it will appeal to a different segment of the market - but, well-designed and engineer, it will find a market. Maybe not in the hundreds, but in the dozens, enough to sustain a small boat builder.

Art: You say, the following is holding back development of hybrid boats "1. Energy-Charge acceptance rate/speed by batteries
2. Energy-Storage volume and energy release capability per battery pound
3. Energy-Charger efficiency per gallon of diesel fuel, or wind energy / solar energy capture and transfer"
Your #1 is here in LI batteries that can accept high rates of charge/discharge - with enough amps you can charge a fully discharged LI battery in half an hour.
Your #2 is where great sums of research time and capital are being expended - and we will never have a non-displacement battery boat until lighter, more dense storage solutions are created. That said, there is no reason to not continue with both self-sustaining displacement e-boats and fun, fast, planing runabouts (Cigarette has one BTW) that are plug-in.
Your #3 is half here already. PM motors/generators are 95% efficient - it's diesel technology (or other petroleum-based motors) where development needs to progress to meet this requirement of yours. Essentially your discussion of dollars per mile boils down to internal combustion technology and not hybrid technology. Yes, solar development moves at a snails pace - the best commercially available cells today are still around 22-23% efficient - something that improves only slightly from year to year.

AusCan: Yes, us seniors grew up with wrenches attached to our hands, a block and tackle on the oak tree and perpetual grease under our fingernails. But, with current modern diesels, there's not much a non-professional can do. Change the oil - change an impeller and serpentine belt - add coolant - change filters. That's about it. I had a high pressure fuel line go on my Volvo D6 several years ago. Luckily I had twins and was able to cruise safely to South Port NC. Parts were ordered and the local service tech effected the repair in an hour. Back in my younger years, on board "Skinny Dipper" (a Phil Bolger Black Skimmer I had built in my back yard) crossing the Gulf Stream in a single-handed race Miami-Bimini, I decided to while away some becalmed hours (see? Sailboats are not the ideal "green" solution) by rebuilding my Sea Gull outboard motor, which always could be made to run, but never could be made to run well! A couple hours later, using a pair of pliers and screwdriver, I had torn it down and put it back together. Those days are history for all but antique aficionados.

I have never thought of myself as a "tinkerer," but I am assuming that is a compliment and I will take it in the manner in which it was said. Island Pilot spent well over $1MM developing the award-winning DSe 12m - I have attached some photos of our "tinkering." You can see by the real-boat pix that at her design weight, she floated on her lines - of course, in our mistaken attempt to make the interior as luxurious as possible, we added a lot of add'l weight making what the water "saw" below the WL not at all pretty and sleek. From the model, you can see just how easily driven the design is (again at the design displacement). And, from the power/speed curve, you can get a good idea as to what our expectations were - if we got to six knots, it was almost "free" to go the additional know to seven (see the shoulder of the curve). But, to go any faster, 8 knot or better, energy requirements rose significantly. This is true of most any design - exceed the hull speed, and until you reach a plane, energy needs grow quickly. The goal was 6 knots at 6 kw - and as I recall, that is close to what we achieved in full-size sea trials. Interestingly, the curves for the tank test in Shanghai, the sea trials of the Glacier Bay version in Zhuhai and those of the Steyr version in Miami, ALL have the same characteristics and with scaling, can lay one on top of the other with only minor discrepancies other than the Y axis (power) which needed adjusting (upward). But relative power for each speed remained consistent.

Since many in this forum own full displacement boats, they have already made the decision to go slowly - 8 knots or less - in exchange for efficiency, creature comforts and range using diesel. In real life, there is not much difference between 6 and 8 knots. With a product that can use renewables, plug-in, and/or hybrid power, I have felt that this 6 knot sustainable goal could find a market - again, look to ex-sailors and other baby boomers with time to spare.

One thing not yet discussed in this thread is living on board at anchor (free of dockage costs and real estate taxes) indefinitely without starting an internal combustion motor to meet your energy needs while still have the ability to cruise along the coast or to the Bahamas. This is an intangible that cannot be measured in dollars but in quality of life.

Summing up - did we find a profitable market with our DSe 12m? Nope. Did we have sales? Yes. Unfortunately, these were in the fall of 2008 on the heels of the collapsing economy and many walked away from their contracts on more "normal" yachts, let alone our envelope-pushing DSe. Watching closely at the success of Ranger Tugs, I feel that their size/price is continuing to be viable - with the right package and price, I feel an e-boat will find a market.

Thanks Craig,
5 knots is to be considered but 7 knots w your boat on electrons is off the chart. But give 5 knots the credit it deserves. We go many hundreds of sea miles at 6 knots and 5 knots is just one knot slower.
The easiest way to make your boat more efficient is to remove weight. Lexan windows instead of glass. Less water and fuel ect ect.
However most electric launches are the same hulls as steamboat launches w exaggerated fantail sterns, nearly round midship sections, narrow beams and very low entry angles (sharp bows). These launches are much more efficient than Willards and even sailboats.
So efficiency wise your'e bark'in up a very big tree w a very small dog. But you can probably achieve 3 or 4 knots w the range you specify and have some out of the box boating fun.

deckofficer said:

And the Honda Insight with aluminum body panels, belly pan, low drag, got 73 mpg before the Prius was on the market. .

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Few, if any, realize the impact that the Honda Insight had on the market place. I was keenly aware of the "independence" that was possible if the car was even mildly successful. Because of it's numerous shortcomings, however, it wasn't, which brings us to Marin's point. It took Toyota (as Bob pointed out) to manufacture a car that overcame those "shortcomings" and appeal to those of us that wanted an all electric vehicle that had none of the disadvantages of the Insight. The Prius became the largest selling hybrid in the world and the stimulus for all the other auto manufacturers that scrambled to offer their hybrids. I have owned two, but presently, after suffering from a serious bout of "patriotism", am driving a Ford Focus. (Not even close to the quality of a Prius but that's another story. At the present time I'm trying to figure out how best to rid myself of the Ford and lease another Prius.) Without rereading Marin's posts, but paraphrasing what he said, I believe he eluded to the fact that "all electric" cars are not that endearing to the masses yet. (Cost, range, speed, battery technology, etc.) And they are certainly not! It took a product such as the Prius to appeal to enough people so as to make it a commercially viable (profitable) endeavor and I believe that was the "crux" of his point, which I also subscribe to.

I don't know anyone who is trying to throw cold water on the the eventual success of an "all electric" vehicle. (Unless you throw big oil into the mix.) It's certainly not me! When one comes along and is economical to own, God willing, I will be among the first to have one. Just as I suffered the slings and arrows of owning a Prius when they first came out. (Possibly, some of you will remember that, as some of those arrows came from your quivers. ) When that day comes, the rapid transferring of that technology will appear in our power boats but that day, currently, is not on the radar.

Rueben, tinkerer coming from me is always a compliment and your work and engineering in this field is what inspired me to try envisioning what is possible. I thank you for it and your contributions here have been valuable to me.

Eric, 5 MPH is always adequate especially where I operate in the Delta. Around here if you have to go more than 10 miles to find what your looking for in an anchorage you are either too picky or impossible to please, take your pick. That attitude and my parameters would never cut it up in the PNW but I don't live in the PNW.

This boat will never run an inlet with powerful currents. It will never be out in anything that even resembles a 2' swell, and it will also never be more than 50 miles from it's home berth no matter what's powering it. The fact is none of that applies to my home waters. Eric if you are interested I have a paralel thread running at boatdesign.net under the Hybrid Propulsion sub forum. The folks there thought I was nuts at first too, but before the second page the harshest critics of the project admit that it's feasable. Trust me when I say those guys where and are tougher critics than anyone on this forum when it comes to electric propulsion. There are also a lot of engineering minds that crunch numbers better than most and do not deny the numbers.

rjtrane said:

Summing up - did we find a profitable market with our DSe 12m? Nope. Did we have sales? Yes. Unfortunately, *these were in the fall of 2008 on the heels of the collapsing economy and many walked away from their contracts on more "normal" yachts, let alone our envelope-pushing DSe. Watching closely at the success of Ranger Tugs, I feel that their size/price is continuing to be viable - with the right package and price, I feel an e-boat will find a market.

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Can't wait to respond to this but am heading out the door to go to the Newport beach, CA Boat Show. I'll be certain to review the "all electric" crusing boats that are on display.

(* Coincidentally, the exact time frame when hybrid cars really took off.)

CPseudonym said:

Thanks for that Eeic, I had hoped this thread would smoke you out of that hole you've been hiding in up in Concrete lately. Good to hear from you. I'm going to do some real world testing throughout this summer to get some data points on HP required. If a force gauge falls out of the sky I'll try Reuben's tow rope idea if not my Livingston is gonna get a workout seeing what the GPS will read.

I suspect it will take less HP than most would have me believe to move this old lady along at about 5-7 MPH.

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Craig – Just for S&G...

If you can (would want to) calculate hp needs from these stats that are as close as I can get (might be able to average everything out) it maybe could place a modicum of relationship to your Owens’ electric power needs before you perform tests; at least I hope so and look forward to learning your actual test results. I’ve not tried calculating hp expended in relationship to speed traveled from the following +/- stats (don’t really know how!). Eric or Bob might be good at that!

- Twin screw good condition 1977 350 cid 255 hp Mercruisers / WOT 4300 to 4400 rpm, 21 to 22 knots on GPS at slack tide, smooth water, no wind
- 17 x 14 props
- Hard chine planing hull
- 32’ lwl – my calc
- 33” draft – mfg stat
- 11 degree dead rise angle – mfg stat
- Parallel line to transom off its c/l at waterline - forward curved transom recesses 12” to each hull side junction – my calc measuring from straight rod
- 12’6” max beam at gunnels – mfg stat
- 18K to 19K lbs w/ a load – my calc off mfg stat of 17K
- Either one of two engines running 1850 to 1950 rpm... as per tachometers that I believe are relatively accurate, especially at relitively low rpm
- Off engine prop left freewheeling
- Clean bottom
- Speed attained: 5.5 to 6 knots on GPS at slack tide, smooth water, no wind
- 2 to 2.5 gph fuel use – my calc judging gallons replaced from fill up to fill up

Walt I'd love to hear your thoughts on the Prius. What drives a man like you who could arguably have most any car he desires to own two of them then after taking a break desire another interests me as to why.

You can PM me with it if you wish.

Just saw that Art. Thanks for the numbers.

Craig,
Great! You'll get all you need to know on BoatDesign. After we get back from Canada I'll read the thread.

rjtrane,
If you want to fantasize about boats and cars just around the corner fine .. BUT they will only be in very small numbers and then small numbers and after many years almost certainly we will be all electric. But we have a great deal of oil left and we're discovering more all the time. And until people get smart about what Al Gore warned us about we will be powering boats and cars w oil.

Gas and diesel is way too cheap and the bottom line is cost until people realize the planet may really be in danger. So boats will get smaller and hulls will become even more efficient than sailboats and better and more efficient engines will come to pass so HUGE increases in the cost and availability of dino fuels will need to come to pass before electric boats and cars become commonplace. The immediate future is in more efficient hulls and engines ... mostly hulls.

rjtrane said:

I have never thought of myself as a "tinkerer," but I am assuming that is a compliment and I will take it in the manner in which it was said.

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rjtrane - Yes - I take it as a compliment. In my mind "tinkering" is taking apart things and putting them back together, just to see how they work and then trying to improve on it, just because you love to do it. A mechanic or engineer repairs/builds/designs just to make a living.

You RJT - obviously love doing it.

manyboats said:

Craig,
Great! You'll get all you need to know on BoatDesign. After we get back from Canada I'll read the thread.

rjtrane,
If you want to fantasize about boats and cars just around the corner fine .. BUT they will only be in very small numbers and then small numbers and after many years almost certainly we will be all electric. But we have a great deal of oil left and we're discovering more all the time. And until people get smart about what Al Gore warned us about we will be powering boats and cars w oil.

Gas and diesel is way too cheap and the bottom line is cost until people realize the planet may really be in danger. So boats will get smaller and hulls will become even more efficient than sailboats and better and more efficient engines will come to pass so HUGE increases in the cost and availability of dino fuels will need to come to pass before electric boats and cars become commonplace. The immediate future is in more efficient hulls and engines ... mostly hulls.

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Eric,

You nailed it. Yes, fossil fuel is still relatively cheap and we do have new discoveries, but can the planet tolerate the by products of continued fuel burn at the current rates?

I have just invited Larry Graf via email to join this thread. He, like Reuben, has built 1000's of efficient hulled catamaran power boats, and his latest offering with his new company Aspen Power Catamarans sets a new benchmark in hull efficiency. I did my thesis at CMA on minimum wetted surface hulls, and back in those days we only had fast ferries using these hull forms. Larry's hull (a proa design) is so efficient that at idle from a small 2.0 L diesel manages 3 kt with a 0.2 gph fuel burn. Even at WOT at 19 kt, fuel burn is 8.8 gph.

AusCan said:

Marin,

Have you looked at the Tesla Roadster. It won't tow your boat but could be a lot of fun.

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Very familiar with the Tesla, a neighbor has one. Interesting concept, proves that electric cars don't have to be butt-ugly like the rest of them are. But I'm not real interested in spending a hundred grand for something that won't float or get off the ground.

deckofficer,
Lots of people are trying to conserve and be good to the planet but it's only a drop in the bucket. Huge private pick up trucks are still hot sellers. This government is afraid to tax the people enough to lower consumption and reduce emissions. I think every nation in Europe is doing that but we just keep on do'in what we've done all along like nothing's changed. It's like the nations debt. Everyone's talk'in about it but basically nothing's being done. The problem is HUGE so it needs HUGE solutions and actions.

But buying hybrid cars and building electric boats gets some attention. Like a friend of mine said when I pointed out that his Prius is NOT cost effective he said "Eric someone's got to start". I do conserve just because I'm not a wasteful person but I'm not carrying the green banner and trying hard to change the world until many more get on the wagon.

I do think Craig's project is worthwhile but I'd like to see him use a very efficient hull and go 2 to 4 times as far in his boat.

manyboats said:

I do think Craig's project is worthwhile but I'd like to see him use a very efficient hull and go 2 to 4 times as far in his boat.

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It's important to keep in mind Eric that this is a feasibility study only, I haven't bought any batteries just yet. Bob and Reuben have provided quite a bit of information to this forum lately and frankly it has been hard for me to digest. This thread has taught me about the possibilities and short comings of the technology that I could not relate to before.

Reuben made a great point in a post that most of us have decided to live with low speed boats already. He is talking about electrics traveling at 4-6 knots whereas most here already travel at 8 or less anyway. The most popular thread we have is 500 posts long following Daddyo traveling 6 knots on the East coast. Haven't heard anyone complaining that Daddyo should throttle up that DeFever and hurry up and finish his trip yet. No electric boat will match Daddyo's daily pace, but none of us pursuing the electric option are looking to or claiming that one will either.

Higher efficiency hulls have already been suggested to me at BoatDesign.net and they make sense and if I decide to go forward may be the way I go. The idea of converting something that looks like a more traditional boat came to me with a quip Mark made about a less than attractive solar trimaran. Mark made a great point IMO, techie or not it was kind of a rogue.

I still like the idea of converting the Owens and agree with your earlier post Eric that the hull is easier to push than many here might think. 20 HP or 15 Kw should be fine by several folks estimate. My next step is researching a more slippery mono hull cabin cruiser under 30'. Perhaps a small displacement hull?

LaunchesCraig I'm glad you have BD.net as the information and the willingness of members to communicate is excellent. There are rude people there too but like TF there are very few and conversations on BD usually involve more people it's easier to ignore any one person.

Multi-hulls have their advantages but I consider them too user-unfriendly due to their extreme beam and other special handling problems. In order to keep the two hulls from separating in rough seas the very considerable mass that comprises the structure between the hulls that holds the whole mess together adds a lot of weight. That large mass (weight) puts a big dent in the performance advantages that may come to pass but cats that are designed very well do have less power requirements than a mono-hull. So cats shouldn.t be overlooked. I prefer a trimaran w less structural issues and the ability to carry her greater mass (engine, fuel ect) along the C/L and many other issues. The only boat I designed and built was almost a trimaran. I consider myself considerably open to hull configuration but definitely am partial to mono-hulls.

Yes a really excellent boat to convert would be the Albin 25 .... the early hull is considerably better for low power. The original engine in the Albin was 22hp. Unusual is the fact that Albin designed, built and marketed the 22hp diesel engine and then proceeded to build the boat to go w the engine. Very unusual. I know of no other boat that I can think of that would compare as well as that Albin for your project. They can be easily trailered too. PM me if this interests you.

Re the "easier to push" comments I made about your Owens is 100% related to her light weight. Re the electric power I see no other advantages to the Owens .. other than if you ruin the resale value there would probably be less to loose. With the Albin you could go 2 or 3 times as far w the batteries and you'd lose much less performance by adding more batteries. You could easily add 2 or 3 times as many batteries and go perhaps 6 times as far. Just think'in "out loud" here.

There are steam launch type hulls that would be much more efficient than the Albin but offer nowhere near the user friendly boat to enjoy on the water. A boat like my Willard is far too heavy for the efficiency needed to make a plug-in electric boat practical just because there are much more efficient boats.

Here is another boat w possibilities. The Vashon Pocket Cruiser. As you can see it's very very much like a Willard 30 but I think they are 23'. So much smaller and more trailerable. There are very few of these so will be very hard to find and I think the Albin would be considerably better.

Here is an example of the steam launches I was talking about. These are extremely easily driven hulls and I predict that trawlers with basically this type of hull powered by very efficient diesel engines will become commonplace or even the norm before electric powered boats come to the fore. Click on the word "Launches" at the top of this post. Or ...... "]http://www.steamboating.net/page44.html"

What is that cute double ender in your two photos? Speed? HP? Displacement?

I still like the Scout 30 for e power. I hadn't thought of the Albin. Is that the one with the center cockpit and aft cabin?

With the objections to multihulls, a good alternative would be long and lean. Remember the Martin powerboat based on their Appledoe Pod? The Energy 48 - http://www.arthuremartin.com/images/stories/Energy48/Trawler-Cruiser-Yacht-1982-2.jpg. Talk about a boat well ahead of its time.

It is my contention that for off shore voyaging, regardless of hull type, longer is better. I've always felt that about 55' is ideal. Small enough for two to handle - long enough for readonable comfort in a seaway.

If a person is looking for an off shore e-boat, perhaps long and lean is the answer? Some sort of steadying sail(s)? Could also be made to look half decent.

Most buyers thing boat price is length related. Not really - it's weight related unless you get into exotic construction (ie. MJM).

Long rides better. Is more stable. Takes less power for higher speeds (still less than hull speed). More deck for PV.

We should be at Mystic Seaport Dusting off old, pre-internal combustion motor launches, as you recommend.

It Appears:

Via a fair amount of electric-boat / hybrid-power posting in TF and other forums; as well as from in-depth manufacturer research. Calculations I’ve learned by those that seem to know and from some who have applied and/or are currently applying practical tests... it seems that currently not enough hi-tech marine-power improvements are available to make the general “medium sized – mono hull” pleasure boat capable of doing a really improved cruising capability; e.g. 100 gallon fuel at a decent speed (7 knots?) directly to Hawaii... if I may project that trip as a midsummer, good weather dream example!

Combined, the items mentioned make me think that it will be years before tech becomes advanced enough for the existing power cruisers to be easily, affordably, correctly repowered into truly efficient hybrid marine use.

And, that was/is the main reason that I’ve been researching hybrid marine power... i.e. to breathe life back into the pleasure boating community.

Good Luck and Happy boating Daze! - Art

Art,

There might be 2 candidates that have the lightness and hull efficiency to be able to pull off electric propulsion for longer ranges.

Buzzard Bay 34 - this is a Chris White design and us that are into sailboats are very aware of his designs being easily driven with modest amount of sail up. This power catamaran will do 34 kt on close to the same power that a PDQ 34 does 19 kt.

Aspen C90 28' - this new offering comes from Larry Graf who also designed Glacier Bay cats and is a unique single engine proa design. At 7900 lbs and a clean bottom where one hull has 35% less beam than the driven hull with no appendages to contribute to drag, gives the best fuel burn numbers I've seen. With just that single engine at idle in gear will push the boat a 3 kt on 0.2 gph. That is 15 nm (17.25 statute miles) on one gallon of diesel. At 16 kt fuel burn is 4.6 gph.

rjtrane,

Looks like we think much the same. I really like the boat in your link (forget the name) .. The 48__? It actually looks much like a drastically stretched Willard 30.

As to your love for length I was in a "the longer the better" frame of mind for most of my life ubtill I had considerable experience w my Willard. I consider it a fairly short boat. I love the way she rotates like an aircraft taking off pointing her bow up and over big and even short seas. I've been in a lot of nasty and never had significant water over the bow and on the foredeck. There's something to be said for a short boat.

Don't know what the Vashon Pocket Cruiser has for power, disp, ect but at 23' they must be about half the Willard 30 specs. Don't know if they have ballast either. I'm guessing 7 or 8,000lbs and 15 to 22hp. Most boats get over powered though.

Found a picture of another Vashon. This one being a bit more yachtie. Took it about 7 years ago at Naniamo BC. As I recall it was a good example.

deckofficer said:

Art,

There might be 2 candidates that have the lightness and hull efficiency to be able to pull off electric propulsion for longer ranges.

Buzzard Bay 34 - this is a Chris White design and us that are into sailboats are very aware of his designs being easily driven with modest amount of sail up. This power catamaran will do 34 kt on close to the same power that a PDQ 34 does 19 kt.

Aspen C90 28' - this new offering comes from Larry Graf who also designed Glacier Bay cats and is a unique single engine proa design. At 7900 lbs and a clean bottom where one hull has 35% less beam than the driven hull with no appendages to contribute to drag, gives the best fuel burn numbers I've seen. With just that single engine at idle in gear will push the boat a 3 kt on 0.2 gph. That is 15 nm (17.25 statute miles) on one gallon of diesel. At 16 kt fuel burn is 4.6 gph.

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Thanks, Bob

Here is the marriage of solar and Sky Sail. World wide cruising without rigging, mast, suits of many sails, just fly the kite or solar electric propulsion.
Solar boats and ships - electric vessels developed in Germany | Zero-Emission-Yacht

deckofficer said:

Here is the marriage of solar and Sky Sail. World wide cruising without rigging, mast, suits of many sails, just fly the kite or solar electric propulsion.
Solar boats and ships - electric vessels developed in Germany*|*Zero-Emission-Yacht

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Thanks, Bob - Interesting...

Eric, where do I start? You certainly know what makes my heart tick for boats. We actually looked at both a Vashon 23 and an Albin 25 before buying our Owens with a little more room. The Vashon was a fully re-fit beauty but ultimately the owner was quite a bit prouder of it than I was. Both those boats are on our short list should we decide to downsize our next boat. The Vashon weighs about 5800 lbs and the one I looked at had a 30 HP Volvo if I recall.

When I bought the Owens I did the same thing we all should do when buying a boat, kissed it goodbye. So have no concerns or delusions about resale, but admit that a small displacement hull makes far more sense than a planing hull. Common sense tells me my next boat will be semi or full displacement anyway.

I have one fellow I'm waiting to possibly get some graph data from someone that has a similar hull to the Owens of comparable size. The graphs proved extremely accurate after his build and all his high power test fuel consumption numbers where spot on. If the low end of his graphs are as accurate it shows 3 KW at the shaft is all that required to achieve 6 knots. 20 KW of battery should then get me close to the basic parameters set out with the Owens. Seems pretty optimistic but the graphs definitely proved accurate for the top end data he was only interested in verifying.

The journey continues...

Craig,
The Albin is a small boat but very useable if you don't mind too much bang'in your body against hard things on a fairly regular insignificant basis. The Vashon is much smaller than the Albin. The Albin would probably be a better boat for us now but I've got the Willy and it's more than a good boat.

Do you remember Ben2Go? He was going to build a Spira semi-dory. I'm worried about him as he seemed to drop off the map and mentioned health problems prior.

Would you be interested in a steam launch type of hull? I know a man that has been into steamboats for a long time (more than one actually) and I've bought two dinghies from a man that builds FG boats. He has made launch boats like the link I posted and has a mold.

Fisher made a 26, a 30 and a 36' (English boat) but they are even less available than my Willard. Unlike my Willard they have a fishform hull. Fuller in the bow and skinny in the stern. Again the Albin clearly looks best. Full displacement boats are actually quite rare. Here's a pic of a Fisher on the hard in Craig AK. This is a really rough example but you can see the hull form clearly. I knew a man that had a 26' Fisher in Victoria BC that was immaculate and was powered by a one cylinder 10hp Yanmar. Fuel burn would be very close to a quart an hour.

I'll send you either a PM or email about Ben later Eric when i have time. I still have regular contact with him off the forum. He's a really nice guy.

Fisher is one make I hadn't considered before and need to read more about. I talk to Jeff Spira once in a while too and have a couple of his drawings that I'm awaiting time to build. I love the simplicity of Jeff's flat bottom dory designs.

Reuben makes great points in his posts about boat lengths for serious cruisers as a long slender hull has great advantages. Can't remember his username unfortunately now but the guy with the awesome trimaran in the Philippines on this forum comes to mind. Insanely efficient boat that he built for long range island cruising. I'm firmly committed to under 30' though. We could afford a much larger boat but choose the size we do as it suits "our mission" for use very well. 2 foot itus is not conducive to sound logic IMO.

Steam launches have always been a favorite design of mine.

Fischer Panda "Electric Cruising Experience"

If you're in or near the Netherlands you may wish to visit the Fischer Panda event with 7 electric-powered boats.