Donate Bitcoin

Donate Paypal


PeakOil is You

PeakOil is You

The Stirling Engine (Merged)

Discussions of conventional and alternative energy production technologies.

Re: Stirlingsolar

Unread postby FoxV » Tue 17 Jun 2008, 13:14:25

one of the hallmarks of Sterling engines is their reliability. I can't find a link for it but I don't think a Sterling engine will have any problem matching a Solar panels 20 year life expectancy.

And ultimately because of their simplicity, you could probably repair the Engine yourself, or at least find a mechanic that can do it. In 20 years time, you may not be able to find or afford a new solar panel.

As for the temperatures and pressures involved they are often much less than that of an IC engine.

Btw, these guys are old news. First being reported here in 2004
[Solar 9] Paraboloidal Solar Stirling Cycle Generators
but the good news is that its been 4 years since we first heard of them. That means we're very close to the "We'll have a product to market in 5 years" benchmark.

Only one more year to wait to see if they'll come through

P.S.: Theoretical maximum efficiency of a Sterling engine is:

[align=center](Hot Temp - Cold Temp)
2 X Hot Temp
(Temperature in kelvin)[/align]

Practical efficiencies tend to be around 30% - 35%
Last edited by FoxV on Tue 17 Jun 2008, 13:25:29, edited 2 times in total.
FoxV
Heavy Crude
Heavy Crude
 
Posts: 1321
Joined: Wed 02 Mar 2005, 04:00:00
Location: Canada

Re: Stirlingsolar

Unread postby roccman » Tue 17 Jun 2008, 13:16:23

Had lunch with these guys two weeks ago.

Big plans...

Big big plans.

Contracts signed...ink dried...herculian backlog.

Just say'n.
"There must be a bogeyman; there always is, and it cannot be something as esoteric as "resource depletion." You can't go to war with that." Emersonbiggins
User avatar
roccman
Light Sweet Crude
Light Sweet Crude
 
Posts: 4065
Joined: Fri 27 Apr 2007, 03:00:00
Location: The Great Sonoran Desert

Re: Stirlingsolar

Unread postby TreeFarmer » Tue 17 Jun 2008, 21:12:28

Have any of you seen an attempt to connect a stirling engine to a regular IC engine in a car in an attempt to capture and use some of the waste heat?

I know that the catalytic converter gets pretty hot so it should be possible.

TF
User avatar
TreeFarmer
Tar Sands
Tar Sands
 
Posts: 609
Joined: Tue 26 Jun 2007, 03:00:00

Re: Stirlingsolar

Unread postby yesplease » Wed 18 Jun 2008, 10:43:37

In terms of belt driven car alts the big things on the table for replacing them seem to be TECs and running the alt off the exhaust.
Professor Membrane wrote: Not now son, I'm making ... TOAST!
User avatar
yesplease
Intermediate Crude
Intermediate Crude
 
Posts: 3765
Joined: Tue 03 Oct 2006, 03:00:00

Re: Stirlingsolar

Unread postby Tanada » Sun 21 Feb 2010, 17:44:31

yesplease wrote:In terms of belt driven car alts the big things on the table for replacing them seem to be TECs and running the alt off the exhaust.


Does that mean using a Thermocouple or does it mean something completely different? That would let you have a straight DC current generated instead of using an alternator and having to convert it from AC to DC for the electrical system in the vehicle.
Alfred Tennyson wrote:We are not now that strength which in old days
Moved earth and heaven, that which we are, we are;
One equal temper of heroic hearts,
Made weak by time and fate, but strong in will
To strive, to seek, to find, and not to yield.
User avatar
Tanada
Site Admin
Site Admin
 
Posts: 17050
Joined: Thu 28 Apr 2005, 03:00:00
Location: South West shore Lake Erie, OH, USA

Re: The Stirling Engine (Merged)

Unread postby yesplease » Mon 22 Feb 2010, 03:17:25

Professor Membrane wrote: Not now son, I'm making ... TOAST!
User avatar
yesplease
Intermediate Crude
Intermediate Crude
 
Posts: 3765
Joined: Tue 03 Oct 2006, 03:00:00

Re: The Stirling Engine (Merged)

Unread postby Tanada » Mon 22 Feb 2010, 18:02:20

yesplease wrote:Thermoelectric.


Based on your link and some research online it appears these systems only produce about 10% as much DC current on average as a standard belt driven alternator. The good news I suppose is they can keep running for some time after engine shutdown until the exhaust system has cooled down.

Now if you could use a bunch of these with a handy chunk of vacant land and some black painted metal you might be onto something, but as always price will be a major deciding factor.
Alfred Tennyson wrote:We are not now that strength which in old days
Moved earth and heaven, that which we are, we are;
One equal temper of heroic hearts,
Made weak by time and fate, but strong in will
To strive, to seek, to find, and not to yield.
User avatar
Tanada
Site Admin
Site Admin
 
Posts: 17050
Joined: Thu 28 Apr 2005, 03:00:00
Location: South West shore Lake Erie, OH, USA

Re: The Stirling Engine (Merged)

Unread postby yesplease » Tue 23 Feb 2010, 00:27:31

On average it's closer to ~30% for a passenger car, maybe more but it isn't as cost effective. Something like a semi can easily go w/o an alt IIRC.
Professor Membrane wrote: Not now son, I'm making ... TOAST!
User avatar
yesplease
Intermediate Crude
Intermediate Crude
 
Posts: 3765
Joined: Tue 03 Oct 2006, 03:00:00

Re: The Stirling Engine (Merged)

Unread postby Keith_McClary » Wed 12 Feb 2014, 00:54:21

Facebook knows you're a dog.
User avatar
Keith_McClary
Light Sweet Crude
Light Sweet Crude
 
Posts: 7344
Joined: Wed 21 Jul 2004, 03:00:00
Location: Suburban tar sands

Re: The Stirling Engine (Merged)

Unread postby davep » Wed 12 Feb 2014, 04:48:12

Keith_McClary wrote:You can buy one for $30
Image
http://www.banggood.com/Low-Temperature ... 74187.html?


That's a low temperature differential one, which produces very little power indeed. It's more of an executive toy, but pretty cool anyway.
What we think, we become.
User avatar
davep
Senior Moderator
Senior Moderator
 
Posts: 4578
Joined: Wed 21 Jun 2006, 03:00:00
Location: Europe

Re: The Stirling Engine (Merged)

Unread postby Tanada » Wed 12 Feb 2014, 08:21:28

Reminds me of one of these things
Image

Put it in the sun and it will spin all day from reactive differential heating. You can even prove it isn't high frequency sunlight by using a heat lamp in a dim room.
Alfred Tennyson wrote:We are not now that strength which in old days
Moved earth and heaven, that which we are, we are;
One equal temper of heroic hearts,
Made weak by time and fate, but strong in will
To strive, to seek, to find, and not to yield.
User avatar
Tanada
Site Admin
Site Admin
 
Posts: 17050
Joined: Thu 28 Apr 2005, 03:00:00
Location: South West shore Lake Erie, OH, USA

Re: The Stirling Engine (Merged)

Unread postby sparky » Wed 12 Feb 2014, 09:22:07

.
The Stirling engine has a lousy torque , can't be reveed up either
never took off as a reasonable prospect except in very special applications
such as techno toys
User avatar
sparky
Intermediate Crude
Intermediate Crude
 
Posts: 3587
Joined: Mon 09 Apr 2007, 03:00:00
Location: Sydney , OZ

Re: The Stirling Engine (Merged)

Unread postby davep » Wed 12 Feb 2014, 09:34:39

sparky wrote:.
The Stirling engine has a lousy torque , can't be reveed up either
never took off as a reasonable prospect except in very special applications
such as techno toys


For high temperature differential engines the torque can be quite good. What's interesting is that torque increases under load as rotation speed decreases due to the better heating/cooling as the air passes through the heat exchangers. You'd want a four cylinder setup to ensure that torque is applied at all times throughout the cycle though.
What we think, we become.
User avatar
davep
Senior Moderator
Senior Moderator
 
Posts: 4578
Joined: Wed 21 Jun 2006, 03:00:00
Location: Europe

Re: The Stirling Engine (Merged)

Unread postby Subjectivist » Sat 06 May 2017, 17:00:59

NASA did a nice job developing external combustion multi-fuel engines. Then the Clinton Administration promptly killed it when they came into office. I wonder how things might be different if the DOD had specified these engines for their ground vehicle fleet for the eight years of the Clinton Presidency?

https://youtu.be/H_Vnxapd5fs
II Chronicles 7:14 if my people, who are called by my name, will humble themselves and pray and seek my face and turn from their wicked ways, then I will hear from heaven, and I will forgive their sin and will heal their land.
Subjectivist
Volunteer
Volunteer
 
Posts: 4701
Joined: Sat 28 Aug 2010, 07:38:26
Location: Northwest Ohio

Re: The Stirling Engine (Merged)

Unread postby Subjectivist » Sat 06 May 2017, 20:08:53

Just a follow up, this link is to the NASA report on the project from November 1988. The so called peace dividend from the fall of the Berlin Wall and the break up of the USSR certainly hurt the project a lot, military budgets were drastically slashed even before President Clinton was elected in 1992.

https://ntrs.nasa.gov/archive/nasa/casi ... 018596.pdf
II Chronicles 7:14 if my people, who are called by my name, will humble themselves and pray and seek my face and turn from their wicked ways, then I will hear from heaven, and I will forgive their sin and will heal their land.
Subjectivist
Volunteer
Volunteer
 
Posts: 4701
Joined: Sat 28 Aug 2010, 07:38:26
Location: Northwest Ohio

Re: The Stirling Engine (Merged)

Unread postby Subjectivist » Sun 07 May 2017, 15:53:09

Just found this, the NASA project cited above is the basis of a new engine after all,

stirling engineMuch like what kind of firearm you should own, or what should go into a proper bug out bag, most preppers could endlessly debate the qualities needed in a bug out vehicle. And like any debate among preppers, there is no definitive answer. The perfect vehicle for you will vary depending on your preferences, circumstances, abilities, and experiences. There isn’t a single type of vehicle that is perfect for anyone.

In the future however, there may be a new type of engine that just about every prepper will want in their vehicle. I say “in the future” because this setup was only recently invented by a man in San Antonio named Josh “Mac” MacDowell, albeit for very non-prepper reasons (though he’s not the first person to come up with this idea). Rather than an internal combustion engine, he wants to place a stirling engine in his vehicle.

I’ve written about the stirling engine and its potential uses for preppers before. It was invented in the early 1800’s as a safer alternative to the steam engine, but it never caught on. Thought it’s rugged, simple, easy to maintain, and has stellar fuel efficiency, the engine doesn’t work very well on a larger scale. Its motion is reliant on its ability to exchange heat between the engine and the air, so if the engine is too big, it will struggle to shed heat.

It also can’t shift into different speeds very quickly, which is why it never caught on in the car industry. Not that they wouldn’t be interested. The stirling engine has a fuel efficiency that’s about three times better than a gasoline combustion engine. Unfortunately the stirling takes a really long time to heat up or cool down, both of which determine how fast the engine is running. Those technical hurdles were too much for car companies to overcome.

However, those hurdles are no longer a problem with the technology that’s available to us today. Here’s what stirling engine is capable of, once it’s combined with a hybrid vehicle:

Though mechanically sound, the Stirling engine never caught on in the 1800s, with most businesses choosing to use steam engines for their industrial applications. NASA even experimented with the engine in the early 1980’s, and was able to achieve 54 miles per gallon, but the Space Agency never went any further with the technology. MacDowell borrowed one of these Stirling engines from NASA and began experimenting with it to see if he could use the regenerative engine with 21st-century automotive know-how.

MacDowell coupled the engine with existing hybrid technology, creating a system that will deliver 58 miles per gallon to a Ford F-150 and at least 100 miles per gallon in a smaller SUV. In his model, the Stirling engine runs at a fixed RPM generating electricity that is used to charge the batteries, which drive motors that propel the vehicle.

Using this thermopile technology, a Stirling-powered vehicle can drive at highway speeds without having to recharge. MacDowell also redesigned the Stirling engine to have the dimensions and appearance of a standard four-cylinder engine, making it compatible with existing automobiles. His idea was so brilliant that Texas A&M University became involved in the project, providing MacDowell with technical expertise and a testing environment to aid in the development of the engine.

By using the stirling engine as a generator to power the batteries, as opposed to directly powering the car, this bypasses pretty much all of the problems with the engine. Nothing but the benefits, such as the insanely good fuel efficiency, remain. MacDowell believes that if his experiments are successful, then his setup could replace the internal combustion for most applications in the near future.

So what else could this vehicle provide to preppers, other than giving a vehicle the ability to drive across the continental US on a single tank of gas (which MacDowell intends to demonstrate in a few months)?

For starters, it would be a stealthy car. You could turn the engine off and just run on the batteries if you found yourself in a hairy situation. Second, you would have a power generator everywhere you go, and a massive battery bank to charge whatever electronic devices that you brought with you. If you tried doing that with an ordinary non-hybrid vehicle, you would run the risk of burning out the lead acid battery.

The greatest advantage however, would be the versatility of the stirling engine itself. Since that engine runs on an external heat source, as opposed to an internal combustion engine, you could use pretty much any fuel source you can imagine. You could pour gasoline, diesel, bio-diesel, kerosene, or alcohol in the tank. With a few modifications, you could run natural gas or propane as well.

Though this certainly wasn’t MacDowel’s intention, he’s basically created the perfect prepper car. If there ever comes a time when our society collapses for a prolonged period, and fuel is both scarce and varied, a hybrid car with a stirling engine would be the last car on the road to “run out of gas”, so to speak.


http://readynutrition.com/resources/thi ... _19062016/
II Chronicles 7:14 if my people, who are called by my name, will humble themselves and pray and seek my face and turn from their wicked ways, then I will hear from heaven, and I will forgive their sin and will heal their land.
Subjectivist
Volunteer
Volunteer
 
Posts: 4701
Joined: Sat 28 Aug 2010, 07:38:26
Location: Northwest Ohio

Previous

Return to Energy Technology

Who is online

Users browsing this forum: No registered users and 60 guests

cron