Solar Stirling

[PulseFuelNerd]

Can a ten foot satellite dish collect enough sun power to create a 3-5KW generator for around $7000?

Project SunFlower is solar stirling research and development to do just that.

A stirling engine is a type of engine that self pumps when one side is hot and one side is cold. The greater the temp differential, the greater the output.

You can read about this old technology here:
Stirling engine - Wikipedia, the free encyclopedia

Mirror coating a 10' dish makes a great solar collector. (1100*F)

Because MB storage is limited on the forum, i will post and keep current, our links here:

Green Gas Fuel
ProjectSunFlower

Our vision and gift:
1. Water where there is no life currently.
2. Electric power distant from the grid.

There is much to share, but wanted to get this thread started.
This is an open source, public domain, research and build.

[Stealth]

This is one way to concentrate sunlight for energy. There are other ways, also. You can use a fresnel lens and do the same thing. Be careful though, those fresnel lens can burn something up pretty quick. You can line the satellite dish with mylar( same material that survival blankets are made of),this can make a good reflector. Concentrated sunlight has awesome power potential. You can also concentrate reflected sunlight onto a solar panel and greatly up the potential. The biggest thing with solar panels is to keep them cool under that kind of reflected heat. My idea is to stand them up, attached to a post in a cicle with mirrors or reflected satellite dishes arranged in a circle around them at an angle which reflects light onto them now matter where the sun is in the sky. This eliminates tracking the sun acroos the sky, as it is always shining on some of the solar panels.Good luck with your project. Stealth

[Shane Jackson]

I was actually going to do something similar.... Here is my idea:

Take a large Sat Dish and mount a solar panel on the arm. The size of the panel will be determined by the size of the dish. This will put out up to 8x the rating of the solar panel (based on similar experiments). Now one "problem" is the solar panel will be VERY hot, so install a copper heat sink on the back similar to a water cooled CPU heat sink. Depending on the heat output, you might could drive a steam generator or at minimal a Stirling. You could also use it to provide hot water....

[PulseFuelNerd]

Project SunFlower

Solar Collector
Any device that focuses the thermal energy from sunlight is a solar collector. The ability to multiply sunlight energy by focusing the rays can be very powerful. In theory, temperatures higher than the surface of the sun can be achieved. Melting metal is not difficult. There are several ways to use solar thermal energy. We are only concerned with heating the hot side of a Stirling Engine.

Stirling Engine
A stirling engine is a type of engine with a hot side and a cold side. It will begin to self pump. The greater the temperature extreme the greater the engine strength. We will use the engine output to create electrical power.

Solar Stirling
A mirrored satellite dish can focus sunshine upon the hot side of a stirling engine. The cool side vents to ambient air. The output can turn a permanent magnetic motor electric generator. The electricity can be used immediately or stored.

Sunflower
The sunflower plant naturally tracks the sun during the day and resets at night so it is again ready and waiting for the morning sun.

Project SunFlower
A world bound by energy crisis longs for true energy freedom. Can 10' of sunlight generate 3 kilowatts of power? Sounds to good to be true! Current theory and data supports that an 8'-10' solar stirling can generate 3-5 kilowatts of power. Cost projections range between $7K - $15K. Sunlight is true energy freedom.

Creating a solar stirling is the single most important thing I can and will accomplish. Progress is slow and steady. Perhaps more will see the light and join efforts to see this to market. Instead of asking the obvious: "When will this be available?" perhaps consider asking: "How can I help this project along?".

Stirling One
D3's initial engine concept, although more efficient, lacked in some areas of design and was to advanced for a first build and prototype proof.

Stirling Two
A rhombic drive stirling design was selected and concepted. The design on paper was finished. Materials have been purchased and machining has begun. We expect 1-2 kilowatts of power. Much of Stirling Two has been disclosed into the public domain. The 6" diameter head contains: a single 3.5" piston with a 3.6" throw. Materials are paid for. I have already afforded $4.5K of the project budget.

Z4 Stirling Engine
Advances in technology prompted us to revisit Stirling One ahead of schedule. The working design is not yet completed on paper, but enough is concepted and is solid. I wish I could share more, man, if you could see this.... It is very exciting. This design will be disclosed in detail when we have substantial supporting evidence. Rough project cost for Stirling One (best guess) is $10K - $30K.

The size of this design is half that of Stirling Two- very compact! It has four 2" pistons, each with upper and lower cylinders. However, Stirling One's output is nearly thrice that of Stirling Two. Our lower gear assembly has been named "LP Drive". There are no lateral forces on the piston seals- NONE! Per my request and R&D design, each LP drive is laterally balanced and capable of extreme RPM. The four drives are 90* out of phase and thus, by design, this engine is perfectly balanced. Harmonic vibrations are minimal and can be quieted if warrented. Nominal RPM will suffice for the upper pressure limitations and efficiency targets. The 8" diameter head contains: Four 2" pistons (8 cylinders) with 2" throws, in our "Z4" pattern.

The Z4 Engine is strong. It will likely find applications outside of solar.

[Shane Jackson]

Why not do as I said and run the super steam generated to drive the stirling via a heat exchanger wrapped around the hot side? From there it could be ran into a hot water heater via a closed loop and even more energy collected.

[PulseFuelNerd]

@Shane, Thank you for your input, have you built this?

You must be aware that heat degrades the efficiency of solar cells even faster than their normal life expectations.

Do you have a source for such a solar cell?

Solar cells can not be made at home, I can not support solar cell tech, as it pays into the established energy system.

Sunlight to heat, to steam, then transfering heat to stirling, adds steps and losses. That would be a tall order for the solar cell to make up the difference.

Direct conversion of sunlight to heat on the copper head is non-complex and efficient.

Steam from a passive solar trough is of interest, but is out of the scope of this thread. Best use of that steam is the question. I believe steam turbines are only ~40% efficient- not very high. Best use of steam should be a separate thread.

Stirling efficiencies are across the board, depending on materials and design. I have heard that nasa has developed scary efficient stirlings.

We are closing towards finishing stirling two and i look forward to output data, both on the engine and on the overall solar stirling sun efficiency.

There is support for higher than 50% stirling efficiencies. 30% efficiency puts us well ahead of solar panels. We hope for as high as 80% and are prepared for as low as 30%. The numbers will prove themselves. I believe in data, not conjecture.

@ all, in general, please try to stay on topic.

Note: Stirlings have been around for centuries, they are time proven, and yet it is impossible to purchase one on the web today, anywhere in the world! (not counting toys). Doesn't that seem a little bit odd?

the scope of this thread includes:

open source stirling designs and plans
collector dish/ parabolics
active two axis tracking
system mounting
standard and linear generators
output data

[PulseFuelNerd]

S2, Stirling Two pdf

Here is a now outdated pdf of the stirling two rhombic engine design.

Features include:
copper head
ceramic ring (thermal barrier ***IMPORTANT***)
aluminum cylinder (passive cooling fins)
aluminum gear box (sealed and pressurized w/H2 ***IMPORTANT***)
aluminum/ceramic displacer piston (w/regenerator fins)
aluminum piston (cooling fins- empty to gear box)
teflon seals on piston (outer seals cylinder, inner seals displacer shaft)
aluminum arms w/needle bearings
5" steel gears w/shoulderbolts
1/2" displacer shaft (precision aluminum w/ceramic coating)
displacer bracket
5" output gear
perm motor generator (sealed inside gearbox ***IMPORTANT***)

This drawing proly raises as many questions as it answers.
Russell Philips

[cody]

Check out greenpowerscience on youtube. Here is just one of his vids, but he has enough videos on this topic to keep you entertained for hours such as building sterlings from off the shelf parts and making your own parabolic mirrors, so you may want to check the rest of his vids out also
YouTube - STIRLING ENGINE SOLAR POWER PARABOLIC MIRROR ELECTRIC GENERATOR
There is a particular turbine which is much easier to construct and much more efficient than a sterling engine, but i know you want to keep the topic focused so ill say no more of that.

[PulseFuelNerd]

Thanks Cody, GreenPowerScience is doing some great builds.

Here is my YouTube channel. This discusses the workings of the Rhombic Drive.

YouTube - Stirling Two: Rhombic Model

cheers

Edit: i am reading some pdfs at NASA website. They are only quoting efficiencies in the 20's. Is this accurate??

[cody]

Your engine is lookin very impressive, great work! Do you have any sun tracking circuits yet? To me that seems like one of the hardest parts of this whole operation. But all in all its a pretty simple concept, and a great way to collect energy that for whatever reason just hasnt really been done yet, at least not at the homeowner scale. Im not sure about nasa's figures but im assuming they know what they are talking about. We do know that using a parobolic mirror is much more efficient than the same size solar cell would be at collecting energy. Choosing the appropriate way to harness that energy is obviously the important part, otherwise your back with a poor efficiency and may be back down to the efficiency of a solar panel or worse. I cant wait to do some work in this area as well but im waiting till i get moved to Arizona.

[PulseFuelNerd]

Dish Component Weblinks

http://www.filmtools.com/flexiblemirror.html
http://www.heliotrack.com/Products.html#dualAxisSensor

The first link is where I found my Mylar Film to cover the 10' satalite dish.
I used contact cement- two coatings on each - this is holding so far.

The second link is a two axis tracker. I was very happy to solve this hurdle with cash, only $165.

@Cody, I am in Phoenix, look me up when you arrive. That goes for any phoenicians

[PulseFuelNerd]

Solar Collector Dish

Here is a shot of the satelite dish covered in reflective mylar film.
It is not finished yet.
A 2x4 will burst into flame in 10 seconds.

[PulseFuelNerd]

S2 Drive Assembly

Here is a recent shot of the inner workings of our rhombic drive stirling. This is the guts to the engine. The last few parts are being machined. We should be bolting this together within two weeks.

[cody]

Looking great! Cant wait to see some vids of the system up and running

[PulseFuelNerd]

Latest Stirling 2 YouTube Video

Here is the latest progress on Stirling 2, Enjoy!

YouTube - Stirling 2 - Component Assemblies