Does a medium sized SE exist that could charge 12 V car battery properly?

Discussion on Stirling or "hot air" engines (all types)
Stroller
Posts: 156
Joined: Sat Apr 06, 2024 1:31 am

Re: Does a medium sized SE exist that could charge 12 V car battery properly?

Post by Stroller »

Spacefog_ wrote: Wed May 15, 2024 4:09 pm Does this look legit to you guys? https://www.youtube.com/watch?v=ziZYVbLnSdM
Yeah. 1.4Watt (varying) at full chat looks about right for an enlarged Ky-Ko fan engine design.
It's not going to blow your hat off, but it would trickle charge a motorcycle battery or charge a smartphone.
Fool
Posts: 1023
Joined: Sun Jul 16, 2023 9:14 am

Re: Does a medium sized SE exist that could charge 12 V car battery properly?

Post by Fool »

.
https://seftonmotors.com/products/volo-one-engine

That is legitimate. 1.4 watts at less than 12 volts will have difficulty charging a cellular phone. Won't reliably charge a car battery.

See also:

https://www.modelenginemaker.com/index. ... 32&
Tom Booth
Posts: 4449
Joined: Tue Nov 07, 2006 2:03 am
Location: Fort Plain New York USA
Contact:

Re: Does a medium sized SE exist that could charge 12 V car battery properly?

Post by Tom Booth »

Spacefog_ wrote: Wed May 15, 2024 4:09 pm Does this look legit to you guys? https://www.youtube.com/watch?v=ziZYVbLnSdM
Looks way low to me.

I can get nearly that much out of one of my small model engines with a cheap coin size generator.

A big engine like that should be able to produce much more.

Most likely they are using an automotive alternator or other generator that requires very high RPM to work at all, never mind efficiently.

That is exactly the same engine as my KyKo fan engine. I haven't run any tests but probably could if you want.

I do know from experience though, you need at least about a 5 hp engine geared up a lot for high enough RPM to get anything out of a typical car or truck alternator.

Looks like that generator is actually geared down.

It also looks like they have four timing marks on the generator pulley, which would quadruple the actual RPM.

Hard to say why anyone would do that. Maybe a strobe effect?

Also I don't know, but the RPM seems too high. Maybe the motor is turning the engine?

My KyKo fan runs at a very leisurely RPM with no load, just fan blades. Seems odd to me.
Tom Booth
Posts: 4449
Joined: Tue Nov 07, 2006 2:03 am
Location: Fort Plain New York USA
Contact:

Re: Does a medium sized SE exist that could charge 12 V car battery properly?

Post by Tom Booth »

The eBay ad for those engines says 15 Watts.

Something doesn't add up.
Spacefog_
Posts: 25
Joined: Sat Feb 10, 2024 3:08 am

Re: Does a medium sized SE exist that could charge 12 V car battery properly?

Post by Spacefog_ »

@Stroller - Ok
@Fool - Also looked into that company earlier, does anyone have any hands-on experience with their SE's? Thanks!
@Tom - Yeah that is unfortunately how I feel about the SE industry in general, a lot of claims; not a lot of long term verified performances. Sometimes I wonder where they hide the battery, or if they modified their measuring tools. It's always 'this is what it can perform in optimal conditions', which is never the case :smile:
Stroller
Posts: 156
Joined: Sat Apr 06, 2024 1:31 am

Re: Does a medium sized SE exist that could charge 12 V car battery properly?

Post by Stroller »

Fool wrote: Thu May 16, 2024 11:28 am .
https://seftonmotors.com/products/volo-one-engine

That is legitimate.
Looks like it could do with a bit of balancing work. :neutral:
Waving a voltmeter doesn't tell us anything much either. Running under load? Or not? I'm guessing not, or they'd be proudly showing the illuminated lamps off.

https://youtu.be/ksdhunDEEsI?t=268
Tom Booth
Posts: 4449
Joined: Tue Nov 07, 2006 2:03 am
Location: Fort Plain New York USA
Contact:

Re: Does a medium sized SE exist that could charge 12 V car battery properly?

Post by Tom Booth »

Spacefog_ wrote: Thu May 16, 2024 10:38 pm ...
@Tom - Yeah that is unfortunately how I feel about the SE industry in general, a lot of claims; not a lot of long term verified performances.
....
It seems there was. With Stirling Technology Company, Infinia, NASA etc. up until around 2010. Then something put the kibosh on things (for the domestic market) is how it looks to me.

Just for example:

https://www.nasa.gov/technology/rps/sti ... milestone/
Spacefog_
Posts: 25
Joined: Sat Feb 10, 2024 3:08 am

Re: Does a medium sized SE exist that could charge 12 V car battery properly?

Post by Spacefog_ »

Tom Booth wrote: Fri May 17, 2024 2:21 am
Spacefog_ wrote: Thu May 16, 2024 10:38 pm ...
@Tom - Yeah that is unfortunately how I feel about the SE industry in general, a lot of claims; not a lot of long term verified performances.
....
It seems there was. With Stirling Technology Company, Infinia, NASA etc. up until around 2010. Then something put the kibosh on things (for the domestic market) is how it looks to me.

Just for example:

https://www.nasa.gov/technology/rps/sti ... milestone/
Agree. I've glanced through those before. I should've started this post with - Does a medium sized SE exist that could charge 12 V car battery properly, whether it be pressurized or not; with only air as a working fluid. If not, how many small SE (pressurized or not) would it take.

The best performing FPSE/SE's in general seems to always have another working fluid, and/or expensive, complex. What happened to the KISS-method?

The more I dive into this rabbit hole of SE's the more I wonder if steam engines are slightly more they way to go. That's a topic for another forum and a whole 'nother beast )
Fool
Posts: 1023
Joined: Sun Jul 16, 2023 9:14 am

Re: Does a medium sized SE exist that could charge 12 V car battery properly?

Post by Fool »

TK motors has some DIY small motors that are quite interesting.
.
https://m.youtube.com/@tkmotors991/videos

Steam engines are easier but require constant attention baby sitting the boiler.
Last edited by Fool on Fri May 17, 2024 4:44 am, edited 1 time in total.
Stroller
Posts: 156
Joined: Sat Apr 06, 2024 1:31 am

Re: Does a medium sized SE exist that could charge 12 V car battery properly?

Post by Stroller »

Spacefog_ wrote: Fri May 17, 2024 4:09 am The best performing FPSE/SE's in general seems to always have another working fluid, and/or expensive, complex. What happened to the KISS-method?
KISS is good, but in the case of Stirling engines it's also big and heavy, and wears out its linkage bearings too quickly to send to space. Finely tuned free pistons on air bearings with pressurized Helium is where it's at, and the limited edition domestic 1kW CHP version occasionally turns up on ebay for a couple of thousand bucks.
The more I dive into this rabbit hole of SE's the more I wonder if steam engines are slightly more they way to go. That's a topic for another forum and a whole 'nother beast )
Steam engines need constant attention from a skilled operator, and they're much noisier than Stirling engines (and small Honda gasoline generators). Good fun though...

The only other viable route from wood-fire to battery charging seems to be Thermo-Electric Generators. TEGs. The modules are coming down in price - around $15-$20 for a 6.5W unit on AliExpress. 10 of those plus some watercooling kit and a heavy duty heatsink to keep the hot side thermally and mechanically stable. Along with some sensors and thermionic valve control or bimetallic strips to prevent burnout, that could give you a silent and long lived 65W output. I've bought 10 cheaper units at $2.50 each to play with and learn from before I try the pricier ones. That's the other nice thing about TEGs. You can swap out dead modules for new/better easily without having to do a full redesign or remanufacture of your generator.
Spacefog_
Posts: 25
Joined: Sat Feb 10, 2024 3:08 am

Re: Does a medium sized SE exist that could charge 12 V car battery properly?

Post by Spacefog_ »

Fool wrote: Fri May 17, 2024 4:41 am TK motors has some DIY small motors that are quite interesting.
.
https://m.youtube.com/@tkmotors991/videos

Steam engines are easier but require constant attention baby sitting the boiler.
He makes great SE's. Always amazed how fast they go considering the materials he's using. Imagine what he could do with better materials/tools. Anyone know if he's still around, or at least a member of this forum?
Stroller
Posts: 156
Joined: Sat Apr 06, 2024 1:31 am

Re: Does a medium sized SE exist that could charge 12 V car battery properly?

Post by Stroller »

Spacefog_ wrote: Fri May 17, 2024 5:14 am Anyone know if he's still around, or at least a member of this forum?
Sadly, no. He passed away a couple of years ago.
Spacefog_
Posts: 25
Joined: Sat Feb 10, 2024 3:08 am

Re: Does a medium sized SE exist that could charge 12 V car battery properly?

Post by Spacefog_ »

Stroller wrote: Fri May 17, 2024 4:42 am
Spacefog_ wrote: Fri May 17, 2024 4:09 am The best performing FPSE/SE's in general seems to always have another working fluid, and/or expensive, complex. What happened to the KISS-method?
KISS is good, but in the case of Stirling engines it's also big and heavy, and wears out its linkage bearings too quickly to send to space. Finely tuned free pistons on air bearings with pressurized Helium is where it's at, and the limited edition domestic 1kW CHP version occasionally turns up on ebay for a couple of thousand bucks.
The more I dive into this rabbit hole of SE's the more I wonder if steam engines are slightly more they way to go. That's a topic for another forum and a whole 'nother beast )
Steam engines need constant attention from a skilled operator, and they're much noisier than Stirling engines (and small Honda gasoline generators). Good fun though...

The only other viable route from wood-fire to battery charging seems to be Thermo-Electric Generators. TEGs. The modules are coming down in price - around $15-$20 for a 6.5W unit on AliExpress. 10 of those plus some watercooling kit and a heavy duty heatsink to keep the hot side thermally and mechanically stable. Along with some sensors and thermionic valve control or bimetallic strips to prevent burnout, that could give you a silent and long lived 65W output. I've bought 10 cheaper units at $2.50 each to play with and learn from before I try the pricier ones. That's the other nice thing about TEGs. You can swap out dead modules for new/better easily without having to do a full redesign or remanufacture of your generator.
I hear you. I've already been down that rabbit hole as well :smile:

https://www.reddit.com/r/woodstoving/co ... oelectric/

https://www.youtube.com/watch?v=-bCVMh5iXAQ

https://indigirka2.weebly.com/indigirka-2.html

The general consensus seems to be that if you don't baby the TEG's they'll get damaged, because they could only take a certain amount of temperature. Know anyone with long-term experience with TEG's that can vouch for their durability and efficiency?
Tom Booth
Posts: 4449
Joined: Tue Nov 07, 2006 2:03 am
Location: Fort Plain New York USA
Contact:

Re: Does a medium sized SE exist that could charge 12 V car battery properly?

Post by Tom Booth »

Spacefog_ wrote: Fri May 17, 2024 4:09 am
Tom Booth wrote: Fri May 17, 2024 2:21 am
Spacefog_ wrote: Thu May 16, 2024 10:38 pm ...
@Tom - Yeah that is unfortunately how I feel about the SE industry in general, a lot of claims; not a lot of long term verified performances.
....
It seems there was. With Stirling Technology Company, Infinia, NASA etc. up until around 2010. Then something put the kibosh on things (for the domestic market) is how it looks to me.

Just for example:

https://www.nasa.gov/technology/rps/sti ... milestone/
Agree. I've glanced through those before. I should've started this post with - Does a medium sized SE exist that could charge 12 V car battery properly, whether it be pressurized or not; with only air as a working fluid. If not, how many small SE (pressurized or not) would it take.

The best performing FPSE/SE's in general seems to always have another working fluid, and/or expensive, complex. What happened to the KISS-method?

The more I dive into this rabbit hole of SE's the more I wonder if steam engines are slightly more they way to go. That's a topic for another forum and a whole 'nother beast )
There were, I think, a number of Stirling engines built that were self pressurizing with atmospheric air. They would start out relatively low power, running an air compressor of some sort and gradually build up pressure and thereby power.

I think "Jim dandy" was the name of one, semi- DIY.. the details, as I recall, are rather sketchy though. I seem to remember having to resort to the Wayback, internet archive for what information is available.

(Looking....)

https://web.archive.org/web/20050930234 ... jimd6.html
Spacefog_
Posts: 25
Joined: Sat Feb 10, 2024 3:08 am

Re: Does a medium sized SE exist that could charge 12 V car battery properly?

Post by Spacefog_ »

There were, I think, a number of Stirling engines built that were self pressurizing with atmospheric air. They would start out relatively low power, running an air compressor of some sort and gradually build up pressure and thereby power.

I think "Jim dandy" was the name of one, semi- DIY.. the details, as I recall, are rather sketchy though. I seem to remember having to resort to the Wayback, internet archive for what information is available.

(Looking....)

https://web.archive.org/web/20050930234 ... jimd6.html
Interesting! I might buy Brent's book just so I can read the interview with Jim, and what improvements he suggested. Just hope this is not another one of those SE's building up to be a small bomb by self pressurization.
Post Reply