Organic Rankin Cycle machine

[Harold in CR]

Just finished watching a video of the machine in action. Sustained output of 100 watts for now, running off a gas fired water heater as the boiler. It DOES run self sustaining, and, can be modded to produce more power.

The video was in spurts. My DSL is minimal, and, the house was shaking, making it tough to watch and listen, while checking the news for severity of the temblor.

I will post a link, once the house stops moving.

Here

[TylerDurden]

Still shakin?

[Harold in CR]

No. It calmed down. Reports, IF I understand the news channel, 5.9- 6.7. About 120 miles from where I am.

[liveforphysics]

It's like a very very poor efficiency, more complex Stirling engine.

[spinningmagnets]

I've been in discussions for a while over solar-Stirlings and solar-ORC. Yes they are inefficient, but all that means is that the engine will be big in exchange for a small amount of power. I've been fortunate to be in contact with some experienced engineers who have been able to answer my questions, and I have spent some time reading the archived chat and files at the Hot Air Engine Society (HAES).

ORC is a steam-cycle, but by using Freon, Propane, Butane, Toluene, etc...instead of water, the boiling takes place at a lower temperature. Using water in a solar steam engine requires a very large collector to run a very small engine (Mojave SEGS). Solar-ORC is much smaller than using water for the same power output.

My interest is that in spite of the obvious engineering inefficiencies involved, solar is "free" fuel...(of course only when to sun is shining!). The Chena Hot Springs in Alaska uses geothermal ORC (though no fracking). There are only a dozen or so places around the country where a city has appropriate resources to build a geothermal-ORC that makes sense. Solar-ORC/Geothermal-ORC isn't a big-picture solution for the world,...or for the US, but...

I can build one if I want, and when the suns shining, I could charge some flashlight batteries, and perhaps a laptop/MP3 player...

[Harold in CR]

I fully agree with Luke and Spinningmagnets. My thoughts are, the same as SM. Efficiency doesn't matter all that much, as long as the fuel is cheap or free.

I am constantly trimming trees and burning the debris. A unit similar to the one shown, could be utilized for much more than 8 hours per day, here. I don't have that "day job", so, I get to play a bit more than most. My water supply for a Micro-hydro system, is not sufficient to supply what electricity I need, all the time.

As everyone knows, energy prices are ever escalating. Mine should go down, eventually. My biggest problem is inferior quality of the commercial electricity. It's hell on electronics. Also, being at a higher elevation, we are susceptible to a LOT of lightning.

The machine in the video was built by someone with NO education of how the system worked. He researched, and then, built the machine with off the shelf parts. Thats the same approach as here on the ES. I'm impressed.

I'm very familiar with model steam-Sterling-and flame licking engines. My Dad was a collector. All the hot air stuff is weak, but, scale it up, and it will produce like a small stream, all day and possibly all night.

These systems can be made to run self sufficiently, no outside source of Petro-energy needed. The one in the video is gas powered water heater, so, a large solar collector can extend the run time, or, wood heated water.

[bigmoose]

I recently went trolling for information on the Baxi combined heat and power engine. The thread is here: http://endless-sphere.com/forums/viewtopic.php?f=41&t=36679&p=532836

This unit has a 1Kw hermetic Stirling cycle generation system, but tuned to 50 Hz. The good news is that it appears you can buy one outright, the bad news is that it is $8,700 US. I think one would find that it is the most efficient Stirling energy conversion system commercially available in that size. It has it's own grid tie included (from my reading of the specifications in that thread) and runs on natural gas. I originally thought that it only ran at full load BTU input; but again, re-reading the specifications implies that it can throttle for just what is needed for the 1 Kw electric power generation need.

It would sure be interesting to get one of these and start hacking!

PS: I really like the use of a dryer cabinet the way he used it. I never thought of that. Dryer shells are light, strong and dirt cheap at the metal recycler.

[spinningmagnets]

When it comes to generating electricity, in order to transport the power from a large central plant to a distributed network, you NEED high-voltage AC (thousands of volts). This is why the well-researched Mojave SEGs plant (supplying peak air-conditioning power to Los Angeles/San Diego) uses a water-steam cycle. The high-temp differential/high-pressure differential turbines generate the thousands of volts needed.

Since the Chena Hot Springs is for local generation (self-sufficient small town in the middle of nowhere), ORC is not only an option, it is hugely less expensive. They would only need 440V/220V, allowing them to adapt affordable and available off-the-shelf components.

I love Stirling engines, I transcribed the Rider-engine patents into plain text (posted for public use in the HAES files). Over 30,000 of them were sold to railroads and hotels just before the proliferation of electric motors (powered by coal-piston steam-powered generators). They came in several sizes, all of them being a parallel two-cylinder vertical Alpha, with the crank on top (pistons compressing down).

The Beta configuration uses a single cylinder for both functions (displacer slug + power piston) via a complex linkage. It is lighter (lower shipping cost) and less expensive to make (lower price). My interest in the Rider is that it is the most developed of the Alphas (why re-invent the wheel?), and it is easier for the home enthusiast to make in a garage than a Beta. If I was actually building one, it would be a twin-Gamma built on the principles of the Rider patents.

A solar-Stirling has a lower pressure differential than a solar-ORC, so the ORC is going to be smaller for the same power output. The benefit of the Stirling is that (if the power from the size you can build is adequate) the working gas is air, so leakage can be refreshed on each stroke. The Rider used an air-pump and relief valve to maintain the internal air pressure at two atmospheres.

If you're not talking about garage-DIY or the third-world, theres a case to be made for building a seal-less helium Stirling.

He would have preferred 3 or 4 atmospheres (denser air creates more power for a given size of engine) but,...organic oil/grease ignites at 3 atm. (in the 1880's he didn't have silicone lube, stainless steel, and teflon seals like us). ORC leakage can be reduced and managed, but ultimately it costs money to keep it occasionally recharged.

[Harold in CR]

My Dad had a Rider-Errickson water pump. It was a 6 X 5 IF I remember correctly. It was heavy for it's size. It was built before they made cast iron leg frame to hold the engine. We used a torch and 1" solid bar to make the 4 round legs. It had a square "fire box" under it, and, he just put a propane water heater burner inside the box, for demo's.

The water pump was brass and very small. It was originally used to pump water up to an overhead tank, when the wind wasn't running the wind mill. It did not have much power. I didn't mess with it all that much to know if it needed rebuilding or what.

Flashsteam .com has some info on modern steam stuff, and, there is 1 contributor who has a neighbor's video posted, of a rotary steam engine, running from an electronically operated boiler. Has a pump to add water to the reservoir and self regulates the whole boiler set up.

My neighbor was here last night, asking me to do some photos on the computer. He has a large Dairy farm for this area, and, a stream of water that would fill a 6" pipe easily, and it runs 200' downhill, right past his Dairy barn and remodeled house. Remote location. He is having the electric power co put in a line .

He also showed me photos of his waterfall, where hundreds of gallons per hour are just running down the hill.