looking for a design

This is very much the style I enjoy. How badly would this roll? or if ballasted properly, could it be stiff?

Ill hop on over to the forum you mentioned. Thanks for the post. beautiful hull. Im guessing they stopped making hulls like this because they rolled too much? or would it have been because of the difficulty, I.e. the skill involved in making one.?

 

Diesel engines are not cheap, but where are the "cheap" steam engines ?

 

yes!!! This is exactly why I like steam, slow turning. Big efficient props. and almost silent running. The ones I've seen from the shore running make almost no noise from outside the boat. I think is what draws me to it. great posts. Thanks for going to the trouble to find that. I assume they could be scaled to 10%? where in gods name did you find those?

 

How much water needs to be carried, and is it recovered by condensing ?

 

Steam has some advantages and several disadvantages. Weight of the propulsion, water and fuel are huge problems, not to mention the volume to stow them. The engines tend to be big too, especially if complex to improve efficiency (multi expansion). This all requires a hull with more volume than a more traditional propulsion system, which requires more power - a dog chasing it's tail situation, in terms of efficiency.

There are low power steam designs that show some promise, but you'll be experimenting with a new engine type and all the headaches this entails. I'd strongly recommend gas or diesel as a much more economical and efficient alternative. For example, where do you find a 30 HP double or triple steam engine, that isn't made by JimBob and his father/brother JoeLarry in the barn, that no one else in the family likes to speak publicly about?

http://www.zenmanenergy.org/assets/img/pics/2_cyl_1a.gif

 

https://www.youtube.com/watch?v=jKu7K6Nu4_A

Eliminate the boiler and water pumps and scaling and all the traditional steam engine problems.

A stirling engine only needs a heat source. Maybe solar. Or a wood fire. Runs even better if the stirling engine cylinders are charged with helium instead of ambient air.

 

Steaming

"There are low power steam designs that show some promise, but you'll be experimenting with a new engine type and all the headaches this entails."

Remember that about 80% of all the power generated in the USA, and the entire world, is generated with steam power. While not a very common type of propulsion for boats, there are plenty of steamboats the world over, and several suppliers of steam machinery suitable for boats ranging from single person rigs to well over the 10,000 - 20,000 pounds displacement regime.
Steam propulsion is nothing new, check out: http://www.steamboatassociation.org.uk which has over 1000 steamers listed and described, in all kinds of sizes, running all over the world today. Also see several youtube videos of the annual steamboat meets at Lake Winnipesauke, NH. Have a look at Dave Thompson's 36 footer, perhaps something similar? http://www.youtube.com/watch?v=PtGeOkOEG4E

Some of them have very impressive performance, not going to win any races with IC engined boats, but that is not what is wanted here anyway. Have a look on youtube at "Steam Launches Oberon and Arlette running at speed on Lake Windermere" http://www.youtube.com/watch?v=BgzSazdIy5s

Of course steam plants are generally heavy and take up more space than conventional IC engines, as well as being far more labor intensive. But they are super reliable, can burn any fuel, and are a joy to operate for some of us.

"A stirling engine only needs a heat source. Maybe solar. Or a wood fire. Runs even better if the stirling engine cylinders are charged with helium instead of ambient air"

Yes, in theory a Stirling Engine might be attractive, but they are simply not available in any practical form for boat propulsion. Power density of the actually available machines is so very low (try finding one that you can buy that puts out more than 50 Watts) that any of several recent attempts in boat propulsion can barely get out of their own way. Steam has a long and continuing history of successful power production.

 

I served on many steamers during 1960's and 70's. I LIKE steam. I love the music of a big triple expansion double acting ships plant. Making 10 kts with a 600 ft ship, the engine singing, "makin money, makin money, makin money."

But takes a lot man hours to operate and maintain. Big black gang!

Personally I like diesel electric. Especially for small craft. While the technology isn't new, there IS new technology in batteries and controllers. And more coming.

 

While I can't see how steam could be doable on such a small budget unless you build the engine yourself, let me suggest one alternative if that is feasible: ORC using HFE 7100 as the working fluid instead of water.

Though not a cheap working fluid HFE 7100 has a number of advantages. First off, it's condensation point is at super atmospheric pressure, which simplifies the design of the already small condenser required by eliminating leaks that contaminate the fluid. If there were any leaks it is considered both non-toxic and sufficiently non-volatile to be "non-volatile" -- something shared by not many ORC working fluids. But perhaps best of all for the pressure ranges small steam engines work at this fluid actually should have a somewhat wider range of associated temperatures that water does, so it doesn't give up efficiency to water in that pressure range. It is true that a stronger pump is needed, and that should be a concern when driving the engine from recovered heat (say off the gas cooler for a producer gas set up as I've considered), however when dealing with a directly fired boiler the fuel efficiency gains associated with the ORC should more than offset that loss. In short, all the claims made all those years ago by the folks touting Naphtha steam, which really didn't apply, can be said to be true with this working fluid.

 

I think steam really is more practical than a stirling. Isnt the cost of a stirling much more?? besides- you still need a fire. or a giant parabolic mirror or something.

 

Im with you on this Fred. I see the steam engine as a great thing to tinker with and although you don't just push a button and go, like an Ic engine it does have a lot of good qualities. Id have no issue building a steam plant even if it does require a lot of space. trouble is finding a good boat. Btw was on that forum of yours. I am now a member.

 

Yea, this should prove interesting, in how fast it can be developed.

I've looked into D.E. propulsion. There was a youtube vid on a 30 ft'er, it was beautiful. Had twin engines I think. but this was state of the art. I went to their website to see what the costs were for the system, and then almost fainted at the price tag. It was in the range of about 60 000 I believe.

It is coming. When we can get better batteries to store the suns energy.

The Late Micheal Ruppert, says there probably isn't too many years left of oil. No one knows for certain.

Yea there are predictions based on energy stores, and "potential" new deposits. but the fact is oil is finite. Of course Methane hydrate might also work. but to get it requires diesel. so if the diesel runs out, hmm now that's an issue.
He states that the reserves of the entire world have about 6 months left at the present rate of consumption.

so might be 6 months or could be twenty years.

when that hits, everything will be used; coal, wood, anything, and life will come to a standstill.

Of course those guys with steam plants, wont be affected by this since in N.A. there is an almost inexhaustible supply of trees. Especially here in Canada. But if everyone had steam power, that too would become the next "oil".

 

Not sure about what you are trying to say. please explain in more simple terms to the simple minded ones like myself. thanks.

Most guys do build 'em, themselves.


new Yanmar 75 hp = about $18 000.

New(homebuilt) steam plant is about at most $10 000, depending if you go for a castings kit.
Definitely a LOT more if your buying an antique shiny brass and spit polished Navy K. The fire tube boilers can be built on the cheap.

wood = usually free + a bit chainsaw gas. Or some callouses and an axe.

oil = 6.90 a gallon here for diesel.

 

Organic Rankine Cycle

" let me suggest one alternative if that is feasible: ORC using HFE 7100 as the working fluid instead of water."

I think there are only a few experimental ORC engines actually built, while the steam technology is 200 years old and there are many people involved with small steam plants. Working up an ORC power plant would have been done by many amateur builders already if it was a relatively easy task, but I havn't seen any at all, except US Govt research studies.

 

I don't want to argue, but there is LOTSA oil under the oceans. just not easy to get at with current technology. But technology ALWAYS changes. Especially when there is need and a market.

People are concerned about pollution. Rightly so. But oil seeps naturally into the oceans daily in HUGE quantities.

http://news.nationalgeographic.com/news/2014/03/140325-texas-pollution-oil-spills-animals-science/


"1. Natural Seeps

Natural seeps of oil underneath the Earth's surface account for 60 percent of the estimated total load in North American waters and 40 percent worldwide, according to the National Academy of Sciences."

that's 40% of worldwide oil pollution is NATURAL.

But pollution isn't my point. It's oil RESERVES. It's leaking out because it's THERE and under pressure. We just need to figure out how to harvest oil a couple of miles beneath the ocean.

Beware the doomsayers. They USUALLY preach inaccurate information, and have a political agenda.