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

[Stroller]

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]

.
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]

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]

The eBay ad for those engines says 15 Watts.

Something doesn't add up.

[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

[Stroller]

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

That is legitimate.

Looks like it could do with a bit of balancing work.
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]

...
@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_]

...
@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]

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.

[Stroller]

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_]

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]

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_]

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

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]

...
@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_]

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.