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Old 05-06-2016, 18:35   #31
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Re: Electric Houseboat concept

Hey Stumble! Thanks for the reply!

Sorry to be a bit vague about it. Think of it as a "prepper" might or maybe "Waterworld" to the extreme. Renewability when all else is unavailable. Solar and wind as well as water power are free and only require (only! HA!) the base hardware to support it. Engines break and need parts and fuel to run. What does one then do when you can't get it any more?

Electric is simple and straight forward. With electrical and electronics, I can repair to component level and some things can be "fudged" and made to work in ways they were not originally designed for to repair a circuit. For example, I can wind my own coils and transformers and have done so. I can build my own high current contactors from spare parts and bits of copper busbar. Smoke a 10k resistor? Strap on two fives. I'm 54 and have been etching and stuffing circuit boards since I was 14. If my guitar rig blew a distortion pedal, I rebuilt the old or built a new one from scratch.

Going with other than "marine" products allows for a greater selection and spare parts at a lesser cost. I don't limit myself with "purpose" or "intent" with materials. In effect, I can have 2 working motors and 2 spares that I can afford that cost the same as one of the "marine" types. Cost efficiency. I know that every one of you all that repair your own have seen the cost disparity between "automotive" and "marine" when it's the same damn part. That part of the industry just irritates the hell out of me.

With the hulls, it's the same. Propulsion efficiency. Sailboats don't have the square footage and layout of living area I want. Picking the best houseboat (NOT sailboat) hull type to allow the best propulsion efficiency, improving the performance of the motor system and eliminating over-engineering just to compensate for the hull drag, therefore, lowering cost of materials. Again, cost efficiency.

Yes I'll start with the basic system and have some fuel usage for the genny initially to keep up during transit, but the system will be grown over time to eliminate the use of a genset to compensate except when absolutely necessary. I retire in 4 years. I want a working prototype ready to go in two. That's 2 years for testing, tuning, and upgrading before I move aboard.

The joy of a houseboat is that I can have it on blocks in the "back forty" at the house to work on until it's ready!
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Old 05-06-2016, 18:52   #32
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Re: Electric Houseboat concept


And I like this one even better!!!! Near exactly what I need. Though..she's a big sucker!!! No sundecks or flybridge. Straight forward. Looks like a house on a barge.
Houseboat For Sale-1974 Stephens 16' x 56'-$12,900 Holly Creek Marina, Dale Hollow Lake, TN
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Old 05-06-2016, 19:29   #33
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Re: Electric Houseboat concept

Hey Stu!

A pair of 10kw engines, isn't going to give you anything close to 10kts. You are probably looking at 10 times that amount of power.

The MOG does it with a pair of 10 hp electric outboards. This was done in 1994! Consider the improvements in technology since then. See the attached MOG log page 1 telling of the beginning of their trip.

The rivers have currents year round. A slow times, the Mississippi can run 3-4kts. If the pair of 10kw engines optimistically gets you 6kts, you run into the problem of "can you make the next anchorage during daylight?"

Or more. There are plenty of coves, creeks, and slews that can be used all up and down the river. If the current is too strong or trouble arose, then you would just nose up on the bank or a sand bar until the issue was sorted. This is why the spare outboard. Nose up, throw a line around a tree and wait or work it out. Drop the outboard, pull off and continue. I won't be spending any more time than necessary on Ole Miss, especially down the south end.

The 60 would be marginal to get any kind of speed.

We'll agree to disagree on that for the moment. Any genset would be augmenting the batteries, not exclusive. I wouldn't put this 60kw on a boat anyway. It's an I-beam skid-mounted 1972 GM that weighs about a ton and a half or better.




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Old 06-06-2016, 00:13   #34
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Re: Electric Houseboat concept

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Originally Posted by Fishman_Tx View Post
Hey Stu!

A pair of 10kw engines, isn't going to give you anything close to 10kts. You are probably looking at 10 times that amount of power.

The MOG does it with a pair of 10 hp electric outboards. This was done in 1994! Consider the improvements in technology since then. See the attached MOG log page 1 telling of the beginning of their trip.

The rivers have currents year round. A slow times, the Mississippi can run 3-4kts. If the pair of 10kw engines optimistically gets you 6kts, you run into the problem of "can you make the next anchorage during daylight?"

Or more. There are plenty of coves, creeks, and slews that can be used all up and down the river. If the current is too strong or trouble arose, then you would just nose up on the bank or a sand bar until the issue was sorted. This is why the spare outboard. Nose up, throw a line around a tree and wait or work it out. Drop the outboard, pull off and continue. I won't be spending any more time than necessary on Ole Miss, especially down the south end.

The 60 would be marginal to get any kind of speed.

We'll agree to disagree on that for the moment. Any genset would be augmenting the batteries, not exclusive. I wouldn't put this 60kw on a boat anyway. It's an I-beam skid-mounted 1972 GM that weighs about a ton and a half or better.




I think you were referring to my comments not stu.

Yes, we will have to agree to disagree but one comment: On some rivers you could nose into the bank. On the Mississippi, that can get pretty risky given the wing dams, high currents and man made nature of the river. There are sections where there simply isn't a good place to stop for many miles. Most houseboats aren't designed for heavy abuse and they rely on lots of HP for speed.

Go look at the attachment you included. The highest SOG was 6kts and the average was 3kts. Presumably the 6kt speed was with a 2-3kt following current as there is tidal current on the route shown. Not sure where you came up with 10kts sustained as practical out of that.
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Old 06-06-2016, 02:12   #35
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Re: Electric Houseboat concept

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Originally Posted by valhalla360 View Post
Go look at the attachment you included. The highest SOG was 6kts and the average was 3kts. Presumably the 6kt speed was with a 2-3kt following current as there is tidal current on the route shown. Not sure where you came up with 10kts sustained as practical out of that.
What's more interesting in that log is that they covered 500 miles (statute?) in 117 hours (about 10 days of daytime travel) but it took them 53 days (11 May to 2 Jul) to do it. An average of less than 10 miles per day.

I guess they spent the other 4 out of 5 days waiting for the batteries to recharge before they started the next leg.
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Old 06-06-2016, 05:03   #36
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Re: Electric Houseboat concept

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Originally Posted by Fishman_Tx View Post
..but one last time...
The point of this whole op is to go fuel free as much as possible. Everything can be run off DC, so lets not argue feasibility as that point has already been proven and is moot. This is about a retired liveaboard with not much money to live on after the fact and needs to be as free as possible from extra expense, specifically and especially fuel.

That said...

I suspect if you compare the costs of the options, including postulated fuel use over a boatload of years...

The plain ol' standard solution for actual propulsion -- fossil fuel, no matter whether from genset or drive engine or outboard or whatever -- could well come in as a factor of half or even a quarter of the cost of a total electric system.

That doesn't address the prepper idea that fossil fuel may not be available... and it's just my first guess... but when it comes to costs, do your spreadsheet comparisons and then see what you think.

IOW, it may or may not be worth it to you to install a "fuel-free" system that really might cost you 2x or 4x as much as a traditional plant. So that kind of candid cost comparison -- up front -- should be key...

Also, can you actually run air conditioning from DC?

-Chris
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Old 06-06-2016, 06:30   #37
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Re: Electric Houseboat concept

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Originally Posted by Fishman_Tx View Post
I want the ability of 10 knots on dead calm for river travel (2-3 apparent going upriver?).
Perhaps I missed it but I have not seen this issue addressed in detail. 10 kts is not possible with the setup you're describing for several reasons.

First the physics of water flow around a displacement hull limit the maximum speed to 1.34 x the square root of the waterline length of the hull. So if you had a boat with a 49' waterline the maximum speed would be 9.38 kts. In real life

1. 1.34 X sq rt of the waterline is the theoretical maximum with a perfect streamlined hull design. A barge shaped houseboat would be lucky to get 75-80% of that.

2. Even with a very streamlined hull as you approach the limit the power required to reach that speed increases dramatically. With electric that means the power you use increases dramatically.

Bottom line, even if you cover every inch of the boat with solar panels you will not generate enough power to sustain even 8-9 kts without supplementing the power with a generator that will of course require fuel.

Of course there are ways to exceed the max speed with a boat. Most obvious is a planing boat like a ski boat or bass boat. With enough power the boat rises on top of the water and is no longer limited by the restrictions of water flow around the hull. The however takes a huge amount of horsepower and again exceeds the capacity of any solar power system.

The other option is a very long, narrow hull or a pair of them, think Hobie Cat or a pontoon boat. The problem here is that option is restricted by weight and once you put a house on the hulls you once again have to add giant horsepower.

I just met a guy that took an old sailboat with no mast and turned it into a solar powered boat. The boat basically has a roof of solar panels from bow to stern. He's been cruising the boat for a while around FL and the best he can sustain on a calm, bright sunny day is a few knots, 3-4 if I recall correctly. That is a speed through the water so any currents will reduce that further.

I've look at electric multiple times and come to the following conclusions.

1. Unless you go for a very small system that is only suitable to get from a dock to the ocean it will be a LOT more expensive than a regular engine.

2. There is no practical way to sustain a cruising speed more that 2-4 kts over a long distance with solar. It can be done but would require either a large, very expensive generator and/or a few thousand pounds of very expensive batteries which still have to be charged requiring more (expensive) solar panels than will fit on a typical boat).
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Old 06-06-2016, 09:48   #38
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Re: Electric Houseboat concept

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Originally Posted by StuM View Post
What's more interesting in that log is that they covered 500 miles (statute?) in 117 hours (about 10 days of daytime travel) but it took them 53 days (11 May to 2 Jul) to do it. An average of less than 10 miles per day.

I guess they spent the other 4 out of 5 days waiting for the batteries to recharge before they started the next leg.
Good possibility (probability?). But still a good proof of concept. Now to build upon those things that they have done going forward.

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That said...

I suspect if you compare the costs of the options, including postulated fuel use over a boatload of years...

The plain ol' standard solution for actual propulsion -- fossil fuel, no matter whether from genset or drive engine or outboard or whatever -- could well come in as a factor of half or even a quarter of the cost of a total electric system.

That doesn't address the prepper idea that fossil fuel may not be available... and it's just my first guess... but when it comes to costs, do your spreadsheet comparisons and then see what you think.

IOW, it may or may not be worth it to you to install a "fuel-free" system that really might cost you 2x or 4x as much as a traditional plant. So that kind of candid cost comparison -- up front -- should be key...

Also, can you actually run air conditioning from DC?

-Chris
The cost comparison between fuel vs electric is moot. Electric will be installed and solar and/or diesel-electric operation is yet to be determined with the goal of 100% electric as the end result eventually, if not initially.
Re: DC a/c: Yup, they make them.


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Originally Posted by valhalla360 View Post
I think you were referring to my comments not stu.

Yes, we will have to agree to disagree but one comment: On some rivers you could nose into the bank. On the Mississippi, that can get pretty risky given the wing dams, high currents and man made nature of the river. There are sections where there simply isn't a good place to stop for many miles. Most houseboats aren't designed for heavy abuse and they rely on lots of HP for speed.

Go look at the attachment you included. The highest SOG was 6kts and the average was 3kts. Presumably the 6kt speed was with a 2-3kt following current as there is tidal current on the route shown. Not sure where you came up with 10kts sustained as practical out of that.
Re: miss; It is the standard procedure (although the last resort) with tow boats when necessary to deal with issues. Dad's beached or barred tows many times in 40 years on the rivers. There are always areas everywhere you go where you can't beach when you want or need to. Nowhere is ever convenient to circumstances. Adapt, improvise, overcome. make do with what you got.
Re: HP: Yes they do. Hull material choice will be aluminum or steel. Fiberglass is not wise with the probability of encountering deadheads on a regular basis on ANY lake, canal, or river. I've seen houseboats, pirogues, ski boats, jons; all kinds running on the river. I've run it on everything from jon with a 10hp to a 16' glastron with a 110 mercury, not including the tugs (which crew don't really count).
But...
First lets see what can be done at dead calm before worrying about step 45 "The River"

Quote:
Originally Posted by skipmac View Post
Perhaps I missed it but I have not seen this issue addressed in detail. 10 kts is not possible with the setup you're describing for several reasons.

First the physics of water flow around a displacement hull limit the maximum speed to 1.34 x the square root of the waterline length of the hull. So if you had a boat with a 49' waterline the maximum speed would be 9.38 kts. In real life

1. 1.34 X sq rt of the waterline is the theoretical maximum with a perfect streamlined hull design. A barge shaped houseboat would be lucky to get 75-80% of that.

2. Even with a very streamlined hull as you approach the limit the power required to reach that speed increases dramatically. With electric that means the power you use increases dramatically.

Bottom line, even if you cover every inch of the boat with solar panels you will not generate enough power to sustain even 8-9 kts without supplementing the power with a generator that will of course require fuel.

Of course there are ways to exceed the max speed with a boat. Most obvious is a planing boat like a ski boat or bass boat. With enough power the boat rises on top of the water and is no longer limited by the restrictions of water flow around the hull. The however takes a huge amount of horsepower and again exceeds the capacity of any solar power system.

The other option is a very long, narrow hull or a pair of them, think Hobie Cat or a pontoon boat. The problem here is that option is restricted by weight and once you put a house on the hulls you once again have to add giant horsepower.

I just met a guy that took an old sailboat with no mast and turned it into a solar powered boat. The boat basically has a roof of solar panels from bow to stern. He's been cruising the boat for a while around FL and the best he can sustain on a calm, bright sunny day is a few knots, 3-4 if I recall correctly. That is a speed through the water so any currents will reduce that further.

I've look at electric multiple times and come to the following conclusions.

1. Unless you go for a very small system that is only suitable to get from a dock to the ocean it will be a LOT more expensive than a regular engine.

2. There is no practical way to sustain a cruising speed more that 2-4 kts over a long distance with solar. It can be done but would require either a large, very expensive generator and/or a few thousand pounds of very expensive batteries which still have to be charged requiring more (expensive) solar panels than will fit on a typical boat).
Now some real numbers! Unfortunately, we definitely won't be using a displacement hull, but a planing hull. A flat bottom barge style, shallow draft. Don't want to "plow" through the water. Though it is possible to increase the efficiency with a little "rhinoplasty" (nose-job) on the bow to reduce the "wall of water" pushing effect to a little more "cutting" effect.
Battery expense I can handle as well as the weight. I'm in telecom power generation and have access to much that's usable in a houseboat.

------------

Look. In the end, I'll do what CAN be done. No "pie-in-the-sky". First one sets the goal and does what is necessary to get as close to that goal as possible, if not actually achieving it. This goal IS achievable. Maybe not in the way or with the capabilities one would want, but life in this world is always a compromise.
I just don't plan on compromising right out of the gate.
That is defeatist.

See the pic below of C&D and "Bell Cells". All 2vdc 1600 ah cells in 48vdc strings of 24 cells. We use all kinds here; niCads, lead-acid, lithiums, etc. as well as my newest plant yet to be installed. The squares are C&D and the round are Gould-Lucent-Lineage-Tyco "Bell Cells".



Here's another successful concept and THIS is what I'm basically shooting for.
Life at a slower pace, with the solar-powered Bauhaus Barge


BTW, there are 11 strings of 24 cells each in the pic below. This only one of 14 offices I handle.
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Old 06-06-2016, 10:28   #39
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Re: Electric Houseboat concept

All right, here's the lab rat.
45'x14' flat-bottomed barge-nosed hull
draft= 18" no rudder, skegs, drives, etc. bare-bottomed.
gun'l= haven't a clue, though it makes a difference to the weight so we'll just say...
displacement=20klbs just "fur Shnitz und Giggles"

From here out, these are the dimensions I'll be using. What I need to figure is a speed/horsepower comparison to see what it takes to move this hull at what speed.
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Old 06-06-2016, 10:54   #40
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Re: Electric Houseboat concept

"We use all kinds here; niCads, lead-acid, lithiums, etc. as well as my newest plant yet to be installed. The squares are C&D and the round are Gould-Lucent-Lineage-Tyco "Bell Cells"."

Forgot to add newest plant is "molten sodium" before edit timer ran out...
Sorry.
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Old 06-06-2016, 10:58   #41
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Re: Electric Houseboat concept

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Originally Posted by Fishman_Tx View Post
The cost comparison between fuel vs electric is moot. Electric will be installed and solar and/or diesel-electric operation is yet to be determined with the goal of 100% electric as the end result eventually, if not initially.

Fair enough, go for it! Just wanted to suggest that it probably won't be less expensive, might even be much more expensive... so you're going in with eyes wide open.

As long as your primary goal isn't "less expensive overall" it sounds like an interesting project.

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Old 06-06-2016, 12:12   #42
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Re: Electric Houseboat concept

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Fair enough, go for it! Just wanted to suggest that it probably won't be less expensive, might even be much more expensive... so you're going in with eyes wide open.

As long as your primary goal isn't "less expensive overall" it sounds like an interesting project.

-Chris
"...eyes wide open"
ALWAYS! Still doesn't stop me from bangin' my nose though! LOL! But I'm the epitome of hard headed. I'll beat that dead horse to a mound of goo before I change tack.

No really, yes fuel is the less expensive option, but the money is not the issue. It's the functionality. I could buy an old hull like that 56' I showed for 12.9k and slap a 200hp mercury on it and be all good. Except that back in the way back woods, there is no fuel. Therefore, electric, as much as is possible and fuel as a secondary only if at all. 100% electric would be nice. It has been done several times and with bigger than what I'm planning to use. In the end, a genny may be necessary within the primary charging equipment and not just an optional backup. I'm trying not to have it that way.
------------------------------

Now...
Given the hull specs, I'm thinking the next steps are thus...

1. First, we need to figure what HP the hull requires to get up to speed and what that speed will be and what it will take to reach the target speed of 10kts, if possible.

2. Second, determine the equivalent electric motor requirement for the HP and the battery capacity and voltage to serve it. 48vdc to start, might need 96vdc to lower current requirements once we see what the HP will be.

3. Third, the type and size of the batteries in the bank to serve the system.

4. Fourth, the quantity and size of solar panels to recharge the system and define the terms and duration of recharge from 60% to 100% with the selected system. Also, define what charging system augmentation (genset) is required, if any, and define the size requirement to meet the specs.

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Old 06-06-2016, 12:51   #43
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Re: Electric Houseboat concept

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Originally Posted by Fishman_Tx View Post
All right, here's the lab rat.
45'x14' flat-bottomed barge-nosed hull
draft= 18" no rudder, skegs, drives, etc. bare-bottomed.
gun'l= haven't a clue, though it makes a difference to the weight so we'll just say...
displacement=20klbs just "fur Shnitz und Giggles"

From here out, these are the dimensions I'll be using. What I need to figure is a speed/horsepower comparison to see what it takes to move this hull at what speed.
Using just those numbers, and assuming displacement at 59,000lbs. There are a couple ways to predict the amount of hp needed at a given displacement speed. But using Gerr's formula B.... (Note this is prop power not hp generated by the engine, so electrical/diesel is all the same you just may need a different transmission)

Speed (kn) ........ Gerr B (hp).. Gerr B (kW)
1 ...................... 11.21 .............. 8.35
2 ...................... 13.89 .............. 10.36
3 ...................... 17.51 .............. 13.06
4 ...................... 22.50 .............. 16.78
5 ...................... 29.58 .............. 22.06
6 ...................... 39.98 .............. 29.81
7 ...................... 55.87 .............. 41.66
8 ...................... 81.45 .............. 60.74
9 ...................... 125.34 ............ 93.47
10 .................... 207.40 ............ 154.66
11 .................... 380.01 ............ 283.37
12 .................... 812.17 ............ 605.64

Displacement hulls are very efficient at low speeds but progressively less efficient as the S/l ratio climbs above 1.34. At which point you need to switch to a planning hull, but with the available power it isn't even worth running the numbers, you would need over 1000hp to discuss getting this on a plane.

To figure out how big a battery you need... Multiply the KW from above by the number of hours you want to run. This gives you the kwh needed, assuming lead acid batteries then multiply by 2 to get the size of the bank you need. Multiply by 1000 to convert to watts instead of kW. Divide by 12.6 to get the total amp hours you will need, then by 100ah to give the number of 100ah batteries you should go buy.

So to run at 5kn (22.06kw) for 8hours, means 176.5kwh.
176.5 X 2 = 352.96 kwh battery bank
Or 352.960 wh
So 28,012 amp hrs
Or about 280 batteries.

At roughly 100lbs per battery, that means an installed weight of about 30,000lbs. Plus cables and battery chargers, and the like. So about half the total displacement of the boat is going to batteries.

If you want to build a spreadsheet the formula is

((kW * h)/DOD)*1000/V/ah = #

kW - users choice based on speed
H - hours
DOD - depth of discharge allowable for the batteries
V - nominal voltage
Ah - amp hour rating of the batteries
# - number of batteries
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Old 06-06-2016, 13:10   #44
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Re: Electric Houseboat concept

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2. Second, determine the equivalent electric motor requirement for the HP and the battery capacity and voltage to serve it. 48vdc to start, might need 96vdc to lower current requirements once we see what the HP will be.

There were threads both here and on Trawler Forum by a lady near where we are who converted a 1930 Elco from a small diesel to electric propulsion... using new a Elco electric drive system, and with Elco advisors. I think that was a 48V system...


I think one result was that she wasn't sure she had met her range goals... but I'm not sure I remember how that turned out...

Anyway, search Starside on both forums (I think) and read those threads, 'cause there's probably some useful detail there. Especially since Elco makes some of this kind of stuff. Even if not a source you end up with, might give you some ideas about products and solutions in the marketplace...

-Chris
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Old 06-06-2016, 13:10   #45
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Boat: 1969 Morgan 40 Cruising Ketch "Lady Catherine II", 1973 Bristol 34 - "Our Baby"(RIP), Catalina 22
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Re: Electric Houseboat concept

Boy, Stumble, that was fast! Thx!
At 59klbs, isn't that a bit overkill? I chose 20klbs because it is real close to actual for the size, depending on whether it's steel or aluminum. An early 70's 36' FG hulled boat ran 13klbs. I know that a 90hp outboard will push it, but to what speed I'm unsure. Most boats of this age ('70s) in the 40-ish range have outboards from 90-130hp, while the inboards seem to like 2x318 Chrysler Crusaders or MerCruzers. I wonder if props or jet drives are more efficient? Hmmm...

Ranger:
Awesome! Thanks for that tidbit. I'm going to check it and see what the spec is if I can find it! I've looked at the Elco gear and they are very pricey, but if I can match the spec, I can find cheaper solutions.
Thanks again!
============

I've also just signed up on the Electric Seas forum for electric drive converts.
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1969 Morgan 40 Cruising Ketch
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