Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 04-03-2016, 16:26   #31
Registered User
 
Island Time O25's Avatar

Join Date: Sep 2014
Posts: 2,019
Re: Could this be a game-changer?

Quote:
Originally Posted by Stumble View Post
It's technically possible but not very efficient. Batteries sacrafice a lot of density to things like electrical channels, liquids, and housings. None of which a solid lead keel have to mess with. Just to run quick numbers... A Rolls-Surretre 4000 series deep cycle battery weighs in at 125lbs (wet) and has a volume of 1,547.1 in^3. A solid lead mass the same size would weigh 634.3lbs. So you would need to increase the volume of your keel by about five times.

Secondly you would need some way to remove the batteries after 5-7 years and replace them with new ones. You had also better use a pretty standard industry casing for them so down the road you aren't locked into one manufacturers battery. Probably a 2v battery she'll of some sort.

Third it would no longer even be possible to upgrade to new battery technology. You would be locked into these batteries.

Fourth, I hope you have finally figured out a way to finally waterproof your bilge, because any water intrusion could easily short out your battery compartment, which is now fully below waterline in the bilge of the boat. Even small leaks could cohort out your entire battery system.
Thanks, that's the explanation I was looking for.
__________________

__________________
Island Time O25 is offline   Reply With Quote
Old 04-03-2016, 16:57   #32
Registered User

Join Date: Jan 2016
Posts: 429
Re: Could this be a game-changer?

Quote:
Originally Posted by Don C L View Post
Of course those are issues with any engine of any type, but this is not a rotary engine. If you are referring to how the piston is lubricated in the cylinder, I am guessing that Toyota and Beetron and others have worked that out. The Toyota diagram shows roller bearings and ceramic coating when there is "insufficient lubricating oil."
Sure, but much more power from a much smaller engine was claimed - edit: sorry, meant "projected" - was it not?
Heat dissipation becomes much more problematic.

These are just my first thoughts about potential issues having encountered them myself more than 35 years ago.
It's true that materials have moved on since then.
Posting only for the sake of discussion & feedback, not saying anyone is wrong.
__________________

__________________
unclemack is offline   Reply With Quote
Old 04-03-2016, 17:29   #33
Registered User

Join Date: Dec 2012
Location: australia
Boat: Mashford Claris
Posts: 32
Images: 1
Re: Could this be a game-changer?

who would use single malt in such a heinous fashion
__________________
takeabow40 is offline   Reply With Quote
Old 04-03-2016, 18:30   #34
Marine Service Provider

Join Date: May 2012
Location: New Orleans
Boat: We have a problem... A serious addiction issue.
Posts: 3,940
Re: Could this be a game-changer?

I am not equipped to make any judgements about the workings of the engine, but if they an shrink a 15kw generator into a 6"x2' package that would be a game changer. At a fraction the weight of a conventional diesel, and a whole lot simpler it really could launch hybrid boats into the realm of possible.
__________________
Greg

- If animals weren't meant to be eaten then they wouldn't be made of food.
Stumble is offline   Reply With Quote
Old 04-03-2016, 19:10   #35
Registered User
 
Island Time O25's Avatar

Join Date: Sep 2014
Posts: 2,019
Re: Could this be a game-changer?

A friend remembers seeing some years back a flat, sideways pistons, diesel the size of a large briefcase, perhaps 10" high. Not a gen set but a working diesel engine pushing a prop. Has anyone seen something like that?
__________________
Island Time O25 is offline   Reply With Quote
Old 04-03-2016, 19:17   #36
Senior Cruiser
 
StuM's Avatar

Cruisers Forum Supporter

Join Date: Nov 2013
Location: Port Moresby,Papua New Guinea
Boat: FP Belize Maestro 43
Posts: 6,709
Re: Could this be a game-changer?

Quote:
Originally Posted by barnakiel View Post
It is sort of like going to a facial surgeon then pretending we are still 18.

The future is the power created in nuclear and fusion plants then stored onboard in 99% efficient cells.

Unless we get onboard fusion generators at a point.

b.
That's currently a looooooooong way in the future.

Doesn't matter how efficient a cell is, the critical issues are specific energy (energy per kg) and energy density (energy per litre). And it's going to be a long time before they come up with other practical energy storage media anywhere near the levels of liquid hydrocarbon fuels.

Diesel is 45 Mj/kg and 38 Mj/l.

There is no currently no battery technology that even approaches 5% of those levels.

Energy densities for various battery technologies currently seems to be doubling every 10 years or so. So if they can keep that up, we should have something comparable to diesel as an an energy store in 50 years or so.
__________________
StuM is offline   Reply With Quote
Old 04-03-2016, 19:46   #37
Junior Cruiser
 
SierraHiker's Avatar

Cruisers Forum Supporter

Join Date: Oct 2015
Location: Northern California
Posts: 10
Re: Could this be a game-changer?

Quote:
Originally Posted by Don C L View Post
...for the electric yacht? Electric motors as an auxilliary notoriously demand more stored juice than most are prepared to load, but perhaps this little jewel might be the next big (little) thing?

a free piston generator seems like it may be pretty efficient at converting fuel to electrons...
Opposed piston technology. especially for diesel engines, is being rapidly developed by Achates Power (Achates Power – Fundamentally Better Engines) located in Sorrento Valley, San Diego. The founder, Dr. James Lemke, developed modern concepts via extending the original opposed piston ideas of Rudolph Diesel, who died in 1913 under mysterious circumstances aboard an English Channel packet boat. Starting in 2000, Lemke extended Diesel's designs via use of modern computers and much more precise engine theory, obtained modern patents and founded Achates Power in 2004. Now, Lemke's vision is becoming a reality with radically new diesel engines that will begin to appear commercially in a year or so. The generator shown here is based on similar concepts and certainly works more efficiently that standard engines. It's not clear to me whether or not this company has secured IP rights to the underlying technology.
__________________
peter
SierraHiker is offline   Reply With Quote
Old 04-03-2016, 20:26   #38
Registered User
 
lonesoldier0408's Avatar

Join Date: Jun 2013
Boat: Luger, Southwind, 21
Posts: 356
Re: Could this be a game-changer?

Quote:
Originally Posted by Island Time O25 View Post
A friend remembers seeing some years back a flat, sideways pistons, diesel the size of a large briefcase, perhaps 10" high. Not a gen set but a working diesel engine pushing a prop. Has anyone seen something like that?

Gemini is a flat, 2 cycle diesel of the aviation usage. As with most engine manufacturers, they have plans to include a marine application.


Still surrounded by anchors.
__________________
lonesoldier0408 is offline   Reply With Quote
Old 04-03-2016, 21:30   #39
Moderator
 
Don C L's Avatar

Join Date: Sep 2014
Location: Channel Islands, CA
Boat: 1962 Columbia 29 MK 1 #37
Posts: 4,375
Images: 34
Re: Could this be a game-changer?

So, issues of heat dissipation, fuel type or taming the electrical flow, etc. are resolvable, I think. I am just (also) thinking that this engine, or this kind of generator specifically, is potentially so much more efficient that perhaps we can see a generator actually drive an electric motor that drives a boat, and the whole system will be more fuel efficient at getting watts from fuel to prop, with more fuel possibilities, than any form of traditional internal combustion, shaft turning, engine, diesel or no. Little Honda generators are nice but they will never be able to approach the efficiency that this design appears to demonstrate. Or am I missing something?
__________________
DL
Pythagoras
1962 Columbia 29 MKI #37
Don C L is offline   Reply With Quote
Old 04-03-2016, 21:34   #40
Moderator
 
Don C L's Avatar

Join Date: Sep 2014
Location: Channel Islands, CA
Boat: 1962 Columbia 29 MK 1 #37
Posts: 4,375
Images: 34
Re: Could this be a game-changer?

Quote:
Originally Posted by takeabow40 View Post
who would use single malt in such a heinous fashion
Only in an extreme emergency, like a few yards from rocks while trying to claw off in a raging storm... then again, that may be a better time to drink it!
__________________
DL
Pythagoras
1962 Columbia 29 MKI #37
Don C L is offline   Reply With Quote
Old 05-03-2016, 00:03   #41
Registered User

Join Date: Apr 2007
Location: Australia
Boat: Island Packet 40
Posts: 1,373
Images: 7
Re: Could this be a game-changer?

Diesel pile driving hammers are two stroke, free piston engines in which the free falling, cylindrical mass in a cylinder concurrently delivers a blow to the head of the pile and compresses a volume of air into which diesel is injected. The expanding burning fuel air mix then drives the piston upwards to reset for the next stroke.


With it's extreme simplicity and minimalist construction the generator in the illustration looks like it could provide a useful alternator in a very compact and light weight, less expensive package than the orthodox equivalent. I wonder how it compares with a conventional genset on a fuel usage/cost/power output basis?
__________________
RaymondR is offline   Reply With Quote
Old 05-03-2016, 06:46   #42
Registered User
 
hamburking's Avatar

Join Date: Feb 2013
Location: Kingston Ont Canada
Boat: Looking for my next boat!
Posts: 2,147
Re: Could this be a game-changer?

Quote:
Originally Posted by takeabow40 View Post
who would use single malt in such a heinous fashion
James Bond...or maybe Richard Branson?
__________________
hamburking is offline   Reply With Quote
Old 05-03-2016, 07:09   #43
Registered User
 
hamburking's Avatar

Join Date: Feb 2013
Location: Kingston Ont Canada
Boat: Looking for my next boat!
Posts: 2,147
Re: Could this be a game-changer?

Quote:
Originally Posted by Don C L View Post
So, issues of heat dissipation, fuel type or taming the electrical flow, etc. are resolvable, I think. I am just (also) thinking that this engine, or this kind of generator specifically, is potentially so much more efficient that perhaps we can see a generator actually drive an electric motor that drives a boat, and the whole system will be more fuel efficient at getting watts from fuel to prop, with more fuel possibilities, than any form of traditional internal combustion, shaft turning, engine, diesel or no. Little Honda generators are nice but they will never be able to approach the efficiency that this design appears to demonstrate. Or am I missing something?
Fuel efficient gasoline engines get about 20% of the thermal "energy" available in the fuel. All the rest is losses, like heat, noise, and vibration. Diesel engines do a little better, achieving maybe 40% under optimum conditions. But most of the time, engines don't run at efficient speeds or optimal conditions.

A linear generator can be set to run constantly at its most efficient setting, since its making volts, not rpm. So you can have a smaller engine running efficiently, rather than a bigger engine running inefficiently.

The test model built by toyota had a thermal efficiency of 42%. And that was just the first try.

The other major area of inefficiency in the conventional marine propulsion system is the prop. Many props have an efficiency of less than 50%. Most of the power is wasted churning up the water, not moving the boat forward. So choosing the right prop is pretty important.

Also, storing electricity in lead acid batteries is not very efficient either. Everyone knows it takes a long long time to get that last 20% of power into the battery. Driving electric motors directly from a linear generator removes that loss entirely.

The common solution to overcoming all these energy losses is to have huge fuel tanks.

Although the linear drive generator is a big improvement on the conventional hybrid system, the real dream is fuel cells. Fuel cells use chemical energy to create electricity with no moving parts at all. Unfortunately, most of these reactions create too much heat. This is great if you are in the arctic.
__________________
hamburking is offline   Reply With Quote
Old 05-03-2016, 09:58   #44
Senior Cruiser
 
StuM's Avatar

Cruisers Forum Supporter

Join Date: Nov 2013
Location: Port Moresby,Papua New Guinea
Boat: FP Belize Maestro 43
Posts: 6,709
Re: Could this be a game-changer?

Quote:
Originally Posted by hamburking View Post
Although the linear drive generator is a big improvement on the conventional hybrid system, the real dream is fuel cells. Fuel cells use chemical energy to create electricity with no moving parts at all. Unfortunately, most of these reactions create too much heat. This is great if you are in the arctic.
If you are talking about the fuel cells that use hydrogen as the fuel, you are right back up against the same old energy density problem. It takes a lot of room to store the energy equivalent of a gallon of diesel.
__________________
StuM is offline   Reply With Quote
Old 05-03-2016, 10:09   #45
Registered User
 
hamburking's Avatar

Join Date: Feb 2013
Location: Kingston Ont Canada
Boat: Looking for my next boat!
Posts: 2,147
Re: Could this be a game-changer?

Quote:
Originally Posted by StuM View Post
If you are talking about the fuel cells that use hydrogen as the fuel, you are right back up against the same old energy density problem. It takes a lot of room to store the energy equivalent of a gallon of diesel.
StuM, you are so right.

But think about all the hydrogen locked into a gallon of water!
Trouble is...water don't burn.
__________________

__________________
hamburking is offline   Reply With Quote
Reply

Tags
game

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
'Game-changing' perovskite solar tech could be cheaper and more efficient zboss Electrical: Batteries, Generators & Solar 4 18-12-2015 07:53
For Sale: Jabsco Porta-Quik oil changer Tim R. Classifieds Archive 1 29-01-2014 07:49
changer? charger? what is it? dinajui Marine Electronics 0 21-03-2013 13:53
Docking Game Stede General Sailing Forum 14 25-05-2010 08:23
Online Sailing Game capt lar Fishing, Recreation & Fun 6 23-03-2006 22:46



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 07:42.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.