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solar power...magnifier engine...seeking input

Started by Wisconsintimber, October 12, 2015, 01:46:53 PM

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Wisconsintimber

So I came across a website by a guy named Darren Holman who is promoting a kit/instructions to build a "magnifier engine" I asume to power a generator and reduce your electricity bill by 50-80%. 

The idea is to use a parabolic mirror to fucus solar energy into a heating chamber and using the movement of hot air to power and move the piston in an engine.  The details are vague which is understandable because he is selling the kit.

I am thinking about buying the instructions and building and am curious if anyone has heard of or tried this?  I am just supprised that if it is possible to build this especially as easy and cheap as they say, that I haven't heard of it before. 

Just looking for insight here...Thanks!

http://magnifierengine.net/video/?aff_id=170&subid=bwreviews&suid=VwKtne7KMd1PH3aLooh2V%2ChHcj4

Ianab

Started watching, but it's got ALL the marks of a scam.

Light on facts, big on hype and "testimonials".

Now it may possible to generate some power with a big mirror, a Sterling cycle engine and a small generator. How much would depend on the size of the reflector and engine, and it might be practical to make one at home that could peak at a couple of Kw. There are even commercial power plants that run like this, although I think they generate high temp steam for better efficiency.

But if the guy is legit he's doing himself a HUGE disservice with his sales pitch as it sounds like snake oil from the outset.
Weekend warrior, Peterson JP test pilot, Dolmar 7900 and Stihl MS310 saws and  the usual collection of power tools :)

beenthere

QuoteI am just supprised that if it is possible to build this especially as easy and cheap as they say, that I haven't heard of it before. 

That should be answer enough... and this guy makes out like a bandit with every kit that he sells.

south central Wisconsin
It may be that my sole purpose in life is simply to serve as a warning to others

Ozarker

Thirty-five years ago, we had a similar idea, using a parabolic reflector to direct concentrated and focused heat into a Stirling engine which drove a generator. The solar tracking would have been controlled by computer, tailored for each locale, which would have taken a lot more to do in those days, than now. The main problem back then was a suitable reflective material to affix to the dish. That, and having enough money to get the project into production. So yes, it can be done, though I agree with Ian that this pitch is a bit off-putting and makes me wonder about the legitimacy and quality of what's being offered.

Wisconsintimber

Yeah I know, the generic website, the dramatic sales pitch, and the too good to be true red flags are flying, but I am a tinkerer so it sparked my interest.  I did google it and some companies like onecarenow and blackwhite reviews have reviewed it with good things to say(although it looked like the same review write up)Is this a scam to cover a scam?  and I don't see any forums or "real people" chatting about it???    But you know if it's on the internet it has to be true :D

Wisconsintimber

The stirling engine does look like a fun and interesting project, but most of the ones I see on youtube or online look alot more complicated and expensive than the claimed $100-$150 cost to build???

pineywoods

Several years ago, NASA (the aerospce guys) had a backburner project to develop just such an engine to power spacecraft. The test engine was mounted in an old dodge pickup and heated with an oil-fired burner. It developed close to 40  hp and motivated the old dodge quite well. A small model mounted in the center of an umbrella-sized dish ran quite well when pointed at the sun. I had my hands on it, so I know it worked. Problem was, when scaled up to full size, the dish covered half and acre and it still didn't produce much power. The data from those experiments is public domain, and probably could be found with some poking around on www.nasa.gov.  The whole project was scrapped when efficient cheap solar panels became readily available. 
1995 Wood Mizer LT 40, Liquid cooled kawasaki,homebuilt hydraulics. Homebuilt solar dry kiln.  Woodmaster 718 planner, Kubota M4700 with homemade forks and winch, stihl  028, 029, Ms390
100k bd ft club.Charter member of The Grumpy old Men

r.man

I also don't like any site that asks me to confirm my navigation when I try to close it. That's a red flag as well. I just saw a fairly informative presentation on mixing up some newer technologies with some older ones, namely evacuated tube solar hot water heaters with a reservoir and a Stirling engine. Looked like an interesting combination.
Life is too short or my list is too long, not sure which. Dec 2014

Brucer

It's easy enough to build a parabolic reflector. I used to do it when I was a teenager, using cardboard covered with aluminum foil. The dish-type reflectors were only approximately parabolic, but still concentrated a lot of heat. Later on I figured out that it was easier to make a U-shaped parabolic reflector and mount it so the axis was horizontal. Easier to "aim" at the sun as well. This arrangement (called a "solar trough") is used in commercial installations

You don't need a computer to track the sun. Just some photo-resistors and a simple electronic circuit, plus a small gearmotor to rotate and/or tilt the reflector. The idea is to mount two photo-resistors just beyond the edges of the reflector, so it's pointed directly at the sun, the photo-resistors produce exactly the same resistance. The electronics measure any difference in resistance and drive the motor until the reflector is pointing where it should.

Years ago I saw an article in the Mother Earth News where someone had made a mechanical aiming device using the same principle. A couple of cylinders (from screen door closers) filled with freon were used to turn a photocell array left or right. Sunlight shining on the cylinders heated the freon causing it to exert enough pressure. If the sun came in at an angle, one cylinder would exert more pressure than the other and shift the photocells until they were pointed straight at the sun.

If you want to see the current state of technology, do a search on "Concentrated Solar Power".

PS: Making a parabolic solar reflector at home isn't difficult. If I were doing it again, I'd probably use a trough design and a reflector made from tinplate. But if you do it, be careful. You can't see the focus point at all -- but you can get a nasty burn just by passing your hand through it. Also remember that you are reflecting sunlight and you can do serious damage to your eyes if you get careless.
Bruce    LT40HDG28 bandsaw
"Complex problems have simple, easy to understand wrong answers."

Ianab

Yes actual the idea of powering a Sterling Engine from sunlight is practical. Any form of heat can make one work.

NASA have been experimenting with using them with a radioactive slug that stays hot for the next 20 years to use to generate power for a space probe. Only needs a few hundred watts to power a probe like the New Horizons that went to Pluto.

There have even been some prototype cars built by Ford, AMC and Opel with Stirling engines. Advantage is they could run on pretty much anything flammable. But they had various disadvantages like slow start-up and shut down, greater weight and poor fuel economy. Might be more useful if combined with a modern hybrid drive system?  Also might work for the Wood Burning Vehicle guys too?

It's the guys "tinfoil hat" style that put me off. Phillips didn't "bury" their patents to various Sterling engine designs. They actually sold some, and licensed the patents to other companies to make other gear.

You could build one of those generators, but it's going to cost a bit of cash and expertise to make it work.
Weekend warrior, Peterson JP test pilot, Dolmar 7900 and Stihl MS310 saws and  the usual collection of power tools :)

pineywoods

Back in my earlier years, I worked for a NASA contractor which gave me access to a lot of interesting projects. Like Ian says, the ultimate goal of the sterling engine project was to provide long term power for deep space probes. They pretty well had the engine design figured out, including the radioactive slug in the head but several problems contributed to the projects demise. One killer was vibration, it messed with the star seeker used for navigation. Another was gas leakage. They used an inert gas (I think helium) for the expansion medium, and slow leaks over long periods depleted the gas. Along about that time, the russians developed a barrel sized thermocouple unit that would make 25 watts for decades, no moving parts. They had their problems too. One of them de-orbited and sprayed hot stuff over a wide area of northern canada. I hated to see the solar variant die, the model worked well, but apparently it just didn't scale up well.
1995 Wood Mizer LT 40, Liquid cooled kawasaki,homebuilt hydraulics. Homebuilt solar dry kiln.  Woodmaster 718 planner, Kubota M4700 with homemade forks and winch, stihl  028, 029, Ms390
100k bd ft club.Charter member of The Grumpy old Men

r.man

Fun fact, at least one of the 10 ft satellite dish manufacturers for tv systems used to make an aluminum dish. I know this because a friend of mine transitioned from doing tv towers to dishes in our rural area. He said you had to really watch out for the sun reflection from one of those dishes. I expect you would also have to make sure you didn't accidentally point it directly at the sun while the LNB was mounted.
Life is too short or my list is too long, not sure which. Dec 2014

Wisconsintimber

Thanks for the input guys...kind of what I figured, the stirling engine is a reality, but not to produce power on the budget and simplicity that is claimed in their add.

Kbeitz

Years ago when you could buy almost anything on E-bay I bought some good stuff.
One of the things I bought was a government surplus parabolic mirror. A very good one.
It's nasty to play with. If you wave a dry board between 17 and 18" in front of the
dish when it's pointed at the sun the board will go up instantly in flames.
I was going to make steam with it to run some of my steam engines.
Never enough time in life to play with all the toys. I paid a couple hundred for it
and I now see smaller ones on E-bay selling in the $1000's
Collector and builder of many things.
Love machine shop work
and Wood work shop work
And now a saw mill work

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