We have finally completed our water well-drilling adventure. Everything that could went wrong – amounting to a 2 month delay – but the bottom line is that we have a 4 inch-bore well that we estimate is giving us 1000 gallons of water per day based on the pumping that we have done so far. We have yet to see whether the well dries up in late summer heat. See our second Factor e Live video (forthcoming by tomorrow) for more documentation on the well.
This means that we are at a great transition at Factor e. The next step is full time work on LifeTrac – and we aim to have it driving in 2 weeks and fully operational with loader, rototiller, and other implements, in 1 month. Our primary attention will go to this – as it is the backbone of the infrastructure for CEB construction – to start on July 15. That’s when the great promise of quality, dirt-cheap building will be tested in practice – as the first example of high-caliber, appropriate technology equipment developed at Factor e Farm. We will then be able to tell if our CEB machine, The Liberator, is worthy of its name.
The next point to mention is the solar turbine– we’re planning ground-breaking on August 15. Our design specification is an affordable, kilowatt-scale, scalable, solar concentrator electric system based on a linear (scalable) reflector Fresnel design of 16-fold solar concentration:
(source). Based on proven techniques, we are predicting exciting results. The bottom line prediction – using overall 8% efficiency (nothing spectacular) from solar input to electric power – is 3 kW of electricity from a 4×10 foot array of mirrors. If we succeed at this, then we will have a breakthrough in solar power generation. What I mean is that none of the ideas utilized are in any way original – but we are putting them together from the systems design perspective – and resulting costs are 2-10 times lower than any system that we are aware of, at any scale of operation. Our calculations show a materials cost of $2000 for the reflectors and collector – plus another $500-$7000 for the turbine, generator, and balance of system. We are talking of costs for solar electricity at 80 cents – $1.30 per installed watt. This is cheaper than coal power plants. Add the labor costs on top of that if you are doing this for outside markets – and we may be talking of replicable power systems that bring about the promise of solar economies.
The trouble is, we’ve heard predictions of cheap solar for many years – but solar cells are still at $5/watt and $10+ for installed costs – and no better alternatives are emerging, except at large scales. How are we any different? We’ll see – but we do have open source methods working for us here. Please continue reading below about our quest for the world’s first replicable, open source solar turbine package. Here we discuss heat engine choices – the universal missing link in such projects.
The solar concentrator part does not appear to pose any serious design or deployment challenges. The working engine choice is our present challenge. We have considered the Tesla turbine, the standard bladed turbine, a piston steam engine, and off-shelf turbines/rotors taken from other applications. We need your help to evaluate these choices or suggest others. Be part of helping to make an open source solar turbine a reality. Here is our evaluation of different options:
Tesla turbine – See link. Proven results show a performance about half as good as that of standard bladed turbines (reference 1 below). Warren Rice shows in a peer-reviewed paper that the best results (1.5 hp for a 5 lb/min flow rate of air) appear to be at least 4 times worse than low-performance piston steam engines (1 hp for 0.6 lb/min steam) such as this off-shelf model. Note that Tesla turbine efficiencies are reported around 20% – but one must be careful about the definition of efficiency used. Advantages: low cost and simplicity of fabrication, scalability – <$1k for a 5 kW turbine. Disadvantages: poor efficiency. Summary: If proven efficiencies are at least 4x worse than standard piston steam engines, then the Tesla turbine should be eliminated as a feasible engine choice.
Bladed turbine – See link. Proven parameters indicate performance (mass flow of 3 lb/min for 5 hp power output for the T-500 turbine) similar to low-performance piston steam engines. Advantages: good performance. Disadvantages: high RPM requires gear reduction. Difficult to fabricate and balance the turbine. No small-scale off-shelf versions are available. Summary: if piston steam engines show similar performance, then it is more effective to utilize a piston engine due to its higher simplicity and lower cost.
Steam engine – the standard piston steam engine appears to be a winner based on performance. Off-shelf, low-performance models produce 3.5 kW of electric power from a steam flow rate of 5 lb/min – which is the theoretical solar steam output from our 10×40 foot array. Advantages: Adequate performance; off-shelf availability. Disadvantages: off-shelf model of 3 kW electric capacity production is $4k. Summary: The piston steam engine could be a proven test bed for OSE’s solar turbine, and other options should be evaluated. Simplification, optimization, and in-house fabrication of said engine will result in <$1k steam engines of interest.
Other turbines – turbine pumps, turbos charger from diesel cars, and tractor centrifugal water pumps (for engine cooling) are good off-shelf candidates for a steam turbine system.
Turbine pumps – these are centrifugal pumps with turbine-shaped propellers. When operating in reverse, they function like a turbine. Advantage: off-shelf, possible low cost. Disadvantage: must be tested for steam operation; efficiency is questionable. Summary: should be evaluated.
Turbo charger – the MIT Solar Turbine is using a turbo charger from a car as the winning engine choice in their 1000 Watt solar thermal electric system (not steam-based). Advantages: a turbo from a car has the turbine shape that we are trying to build – and it is available off-shelf, and on-the-cheap from salvage. Readily testable. Disadvantages: Turbo pump may have to be modified for steam compatibility; are there turbo pumps that can produce a suitable power range? Summary: Should be investigated immediately for feasibility.
Tractor water pump – another option worth exploring. Advantage – readily available from salvage. Should be compatible with steam if it’s designed for near-boiling water temperatures. Disadvantage – what is the efficiency?
Please comment on the above and help us narrow down our choices.
Reference:
(1) “The turbine efficiency of the test model was over 20%, which is fairly good when one considers that it was not in a high state of development. Turbine efficiency for conventional turbines of this size run between 40-50%.” – from Elroy William Beans, Ph.D. thesis, Pennsylvania State University, Department of Mechanical Engineering, June 1961.
My parent’s are finishing a strawbale home in Colorado are using a solar power disc (looks like a sat disc) It turns with the sun and eliminates all of the panels. Something to think about.
This is what the world needs! More folks making an effort to produce cost effective solar power systems. Too much effort seems to go into desigining the “perfect system”
with out any reguard to cost. Admitedly learning how to make it right is the first step. It is long since past the time to take the next step, to make it affordable to the masses.
Bob Coe
Renewable Sources Inc.
(dedicated to making alternative power sources affordable)
Marcin, a quick note about turbocharger pumps for cars:
While I think that steam could easily drive an enclosed impeller from an automotive turbocharger, one small hurdle that you should know about if you don’t already:
Most turbochargers from cars, trucks, etc use a floating impeller-shaft bearing. So, you would need to supply an oil stream with the correct pressure to the beaing, or the turbo would lock up eventually.
However, there are now some ball bearing-based turbos available: http://www.airpowersystems.com/wrx/aps_turbo.htm for example these have better efficiency usually than the floating bearing turbos.
Many large diesel engines also employ very large turbochargers, which may be in the size range you are looking for. Presumably some of these now have ball bearing impeller shafts, too.
Seems like the piston steam engine could be a good way to go. I wonder if there are wome old Wankel engines out there that could be modified to handle steam? http://en.wikipedia.org/wiki/Wankel_engine
I got a response from Dan Granett on turbine engines:
Marcin,
Here is a source of much info on home made turbines. I think some of these people buy off the shelf turbine disks to start with. Truck turbochargers are one source.
http://www.pfranc.com/projects/turbine/top.htm
Dan
Charles Shults at Worldsnest is also using Fresnel lenses, combined with steam engine:
http://peswiki.com/index.php/Directory:WorldsNest:Sir_Charles_Shults'_Concentrated_Solar_Design
Marcin,
So are you still planning on manufacturing the Tesla as part of your experiments? It does seem the easiest to assemble solution if the parts can be fabricated. I too can’t find any verifiable results for an efficient design. Lots of claims but no where to see one actually working. Love to try and build one though just to see. But hate to drop several thousand in the process. In looking at your last set of plans I see fitting the seal as the really delicate part of the assembly. Let me know if you plan to proceed.
Jamie
You may view additional responses to this post at Global Swadeshi Network:
http://www.globalswadeshi.net/forum/topic/show?id=2097821:Topic:1450
Discussion with Sasha:
On Mon, Jun 16, 2008 at 4:18 AM, sasha wrote:
Fantastic Marcin!
Here is a link to a MIT students group which are trying to do
something similar: sturdy, cheap, relatively low tech and yet
efficient and possible to replicate on a bigger scale.
http://web.mit.edu/newsoffice/2008/solar-dish-0506.html
Possibly you can connect with them and learn from them. Would like to
hear your opinion.
Cheers,
Sasha
Sasha,
Yes, this MIT stuff looks decent. I’m not the greatest fan of dish-systems – for lack of scalability. If they can make it work, that would be great. This is similar to http://www.solarfire.org
Now, the challenge is the heat engine. There is no proven alternative for this type of adventure. A low-cost, high efficiency engine is required – if they want to make 3.5 kW – that is an efficiency of about 40% – really high.
That’s also our aim – and the reason I posted my message for collaboration for the solar turbine. I think 40% is achievable via turbines or advanced steam engines. IMHO, Stirling engines are too difficult to fabricate.
All in all, I predict that we will come out 2-4 times more cost effective than dish systems – which have serious structural requirements for wind loads. Especially here – we have winds of 20 mph frequently – and near tornado conditions on a yearly basis.
I would definitely like to talk to them on their heat engine developments.
Please post this on our blog – I’ll make sure to get back to it. See if you can find some explicit contacts for project leaders on this.
Thanks,
Marcin
Discussion from Vinay:
—-
On Mon, Jun 16, 2008 at 9:30 AM, Vinay Gupta wrote:
what do you think of these?
http://www.mikebrownsolutions.com/3hppic.htm
—-
Vinay,
This is the only off-shelf steam engine that I know right now. It is also usable with our system – but we would need 2 of these for full use of the steam that we have – or $4k in cost.
I was advised that a marine steam engine is the best choice that we could find. They are out there – if we could find one for testing – that would be great. Otherwise, we’d need to fabricate one.
The point about steam is that it has never been modernized. The IC engine took over – and now you have a lot of half-time players out there toying with these things. I’be been told that then these people die, and their work is lost.
The advantage of steam is its environmentally friendly and quiet operation. Their power efficiency is comparable to gasoline engines. I think there is certainly a lot of room for steam engines in a sustainable world.
So the bottom line is – if you know of someone who has a stationary or marine engine that they could lend us for testing – then let us know. I think in general – if we work out the details of the concentrator to generate steam – that will be the first step. Once we have that, I think we’ll find some engine for testing. The easiest route would be to identify some collaborator. There’s no point for us to fab our own engine at the proof-of-principle stage of the Solar Turbine project. So please spread the word about this.
Marcin
Discussion from Jamie:
—-
At least this guy has built one and tested it with steam.
http://www.gyroscope.com/d.asp?product=TESLATURBINE2#
James Peebles
—-
Very interesting generator used, high speed. Nozzle direction control – very nice.
There’s many people that made the Tesla turbine – in the toy version. This particular one falls into the category of toys. You can do this yourself by taking regular CDs, putting them on a shaft with spacers – and running air through the system.
I calculate about .2 pounds of air per minute mass flow rate from his 8 cfm figure – for 60 watts of electric power. Sorry to say – Mike Brown’s inefficient steam engine uses about .6 lb/min – to get 500 W of electirc power. So the results here are consistent with my comments on the blog – this turbine is about 3 times less efficient than standard piston engines. This is bad news if we’re stuck on the Tesla option – but good news if we’re to make a system that works.
That doesn’t mean that the Tesla turbine won’t work. It is still very inexpensive to make – and we will experiment with it later. For now, we’re leaning towards the steam engine in the first prototype.
That’s different thinking than what I told you the last time. Afer shaking down the options, it seems the Tesla turbine is not a good choice if we want to do a proof of principle of the solar turbine. What do you think?
Marcin
Interesting discussion with Greg:
Hi Ben and Marcin ………………… You might want to visit http://www.infinityturbine.com and take a look at the
Solar Modules designed by Greg Geise. He’s also behind http://www.butanoljetfuel.com Co2 to Butanol technology. — He and I have already discussed using fresnel lens to build solar collectors to focus solar
energy onto Moringa oil, which is noted for its resistance to high temps, being useful as a cooking oil, and used as a lubricant for precision machinery. It seems reasonable to use Moringa oil as a thermal oil, in order to use built up solar heat to drive Greg’s Infinity Turbine design. — Check out his sites, and get in touch with him to discuss a working Solar Turbine design. —- Peace, Greg O’Neill whtgr@yahoo.com
—-
Thanks, Greg, this is an excellent lead. I like the oil idea – I am looking for replacements for synthetic oil for our hydraulic tractor – LifeTrac – http://openfarmtech.org/index.php?title=LifeTrac
Perhaps water would work in hydraulic power systems – with some component modifications.
Do you mind if I post this comment on my blog – it’s useful for more people to see.
Marcin
—-
Hi Marcin ………… No problemo, you are welcome to post my comments to your blog. Ben and I have already discussed the self replicating approach to building butanol refining units, using Steve Finch’s new
system, membrane/enzyme based. His system doesn’t require distillation or drying equipment, and much more eco-friendly as a result, no EPA issues to resolve. Butanol is biodegradeable, and can replace gasoline, without engine modification needed. — Steve is sending me a note soon on his cost estimate of
building a portable unit, capable of producing 2,000 gallons of butanol per day. I will input that data into my business plan revision, for setting up my White Tiger Farms near Silver City, New Mexico. — Marcin,
have you been over to my site http://whitetiger511.tripod.com yet? —– Peace, Greg O’Neill
—-
Very interesting. Is your work on biobutanol open source? Do you see routes for collaboration? On our side, we are getting into Fischer-Tropsch synthesis of diesel fuels from biomass – it’s proven, and we’ll be doing work to increase efficiency. Is biobutanol proven – or what is the status?
We aim to engage work similar to yours – once we get our technology base up. We will be raising capital via subscription – people who are interested in product.
Marcin
—-
Hi Marcin ………………… It isn’t my work on biobutanol, but developed by an associate of mine, Steve, who has over 17 years of experience working with Manildra Group in Australia. Steve came up with his
proprietary system, and I seriously doubt he would be willing to make it open source. — I do see an avenue for possible collaboration, in getting out Steve’s system far and wide, in portable units that would be leased, instead of sold, enabling communities of all sizes, to get the units close to their sources of cellu-losic material. —- I’d like to dialog on the potential of working with you to turn biomass into diesel fuels, New Mexico now uses 550 million gallons of diesel each year, and biodiesel would certainly go far to re-duce dependence on crude oil-derived diesel. — Yes, butanol is proven, just check out to review the work of Dave Ramey, President/CEO, Butyl Fuel LLC, in Blacklick, OH. Dave used 100% butanol in his own car, on a cross country road trip to publicize butanol’s use as a fuel to replace gasoline. Dave actually got better mpg with butanol than he did with gasoline. — I know that people will be open to buying butanol at $2 per gallon, replacing gasoline at $4 plus per gallon, especially when it frees our country from dependence on foreign oil producers. — Peace, Greg O’Neill whtgr@yahoo.com
I just talked to Greg O’Neill about biobutanol – he’s looking at large plantations in Mexico. He was not willing to go into details, for reasons of open source Culture. I mentioned Fischer-Tropsch synthesis of fuels from biomass – which is what we will be working on with Dr. Yuyi lin of U. Missouri, Columbia. We are interested in personal fuel makers. Wood chips or biomass in – fuel out. The question is if we can make this process viable on a small scale.
From Jamie:
—-
I am forwarding a response from Rob O’Brien. He certainly has some of the know how. Although he is naturally reluctant to reveal some of his intellectual property.
James Peebles
—-
> From: Robert O’Brien
>
> Hi Jamie,
>
> If built as described in the generally accepted literature; the Tesla type turbine will only produce ~ 20 to 25% when operating in gaseous fluid. However, I am presently producing a 3″ diameter Tesla type turbine/generator which performs in the 60% isentropic efficiency range. Kinetic to electric efficiency is >55%. Capacity is 1250 watts. While this is not quite as good as an automotive turbo (~70% isentropic), I can operate on about 1/100 to 1/25 of the mass flow. The unit is still prototype and therefore expensive but it should be in production soon.
>
> I also build and sell gas turbine engines ranging from 20 to 500 kW and I am burning SVO (straight veggy oil) in high performance combustors. I am working with one small group to run glass furnaces on waste oil. We’re hoping to save a whole bunch of small operators who are going out of business due to the rising fuel costs.
>
> I can provide some input to the open source turbine effort but I am not yet willing to reveal my secrets. It will be quite controversial when I do so I need to be prepared. I can provide a design for my very first model, it is already published on my web site. I can also provide lots photos and links to my YouTube channel for videos. I only ask for proper credits in the public release of my work.
>
> Sincerely,
>
> Robert O’Brien
> http://www.obilaser.com
> 1.860.305.0038
>
>
> Jamie’s Mail wrote:
>> Rob,
>>
>> I have been interested in the construction of an open source design for a Tesla Turbine. I appears that it may not have sufficient efficiencies to be a practical Turbine. Based on you experiments with them have you reached the same conclusion?
>>
>> See Link below.
>>
>> http://openfarmtech.org/index.php?title=Boundary_Layer_Turbine
>>
>> Thanks,
>>
Why steam? Why not use lower temperatures, no concentrators, just flat plate collectors, pump to a storage tank, then use a small heat engine, like 500 watt for 24/7 use instead of 3.5 KW for 5 hours a day. Steam is dangerous, VERY dangerous, and at those pressures and temps, a system failure could be very bad. So, I am thinking, compromise efficiency for feasibility and safety. Use simpler collector mechanisms, and then you could build a low efficiency stirling, like a fluidyne or stoddard design, for very cheap. If you had decent thermal storage, then you could run it all night and reduce the size of the engine and generator.
Just some thoughts, but I would stay away from steam and concentrators. Although you can make them safe, they require a lot of additional components and systems AND cost, where as a simple flat plat 2 times the size of your concentrator will collect the same amount of energy at a lower temperature.
Good work, though.
—-
Abe – please show me some data and designs for the fluidyne or stoddard versions of low temperature Stirlings. What are the demonstrated performances and costs? We are open to suggestions. – Marcin
One more option, convert a diesel or small ICE into a steam piston engine. I have seen a few of these on the net. seems fairly straightforward, you’ll loose some efficiency for sure, but it is cheap, and small 4 stroke engines are everywhere (I have about 4 in my back yard). I think Mother Earth news did this way back when with a fridge compressor as well. Maybe there is a pump or engine that would work well.
I have looked further into this idea, and have seen several solar steam projects on the web. Most seem to fail because they can’t produce enough steam. At first, no problem, but as the water cycles through the collector, the volume reduces, and the amount of steam tapers off. Maybe you can overcome this, as I am sure you have seen the same research as I have.
Personally, I still think it might be better to compress a gas (propane?) using heat and power an air motor or an old ICE with the compressed gas. Work with pressures around 50-100 psi and lower temps. No scalding steam exploding in your face… 🙂 Steam scares me, if you haven’t noticed!
You guys be careful!
What is the running log of fluid flow rate, power output, and overall efficiency for the converted ICEs? I know the Australian project at White Cliffs, NSW – http://people.linux-gull.ch/rossen/solar/wcengine.html – and the results there look good. I don’t have a feeling for the difficulty of making the conversion.
Tell me more about the results of steam tapering off? I have not seen this.
http://www.rossen.ch/solar/wcengine.html
http://www.rossen.ch/solar/anu.html
(fixed solar dish with converted steam engine.(look at simple way to get steam in chamber)
Some first time steam engines problem thermal mass of expandtion chamber.(steam condess to water before pushing piston, must keep motor hot)
There are other liqiuds and solutions that go gas at a lower temp. Might have a lower cooling temp. Might come in hand when there is snow abound.
Solar ac units use minerial oil in collected with a heat exchanger/holding tank. Can run after no sun.
Water under perrsure does not expand. Water under vaccum expands at a lower temp
a closed loop sytem can run backwards and use the vacum or both.
I read somewhere someone did what you were trying to do in africa. But pumping water not elec. around 1930(solar trough, steam engine,
I am sure you probly no most of this I just saw a lot of people comminting and just want to spark more insterst.
Everything you are doing is great. I want to do the same thing but at the end of the month bills consume everthing.
Nature gives us everything to live well than man created luguries we can not live without. (someone other than me?)
Incredible stuff/ Will come back again!!
Hi Guys,
Love your work. I saw your first attempts at a concentrator and thought your could use or copy the PDF instructions found here:
http://www.compatibletechnology.org/whatwedo/devices.html#solarroaster
You could also try and replicate this system on larger scale. The use of ubiquitous car parts is a good idea…
http://www.stginternational.org/how-it-works.html
Keep it up, I want to see the finished product!
I have developed steam engines from 2 hp to 20 hp at affordable price. I will be happy to supply for solar power plants.
V K DESAI
AADHUNIK GLOBAL ENERGY
RAJKOT, INDIA.
http://www.tinytechindia.com
energy@tinytechindia.com
In regard to the reference about Infinity Turbines. This company is a fraud, the Infinity Turbine is faulty. Greg Giese is a conman. The Infinity Turbine does not work, just an online scam.
Planet Police and Bel Ola, andlatout, and phones wholesale are the same person and are from Vancouver, BC Canada, and are runnig a spam campaign against Infinity Turbine. This website posts comments fraudulenty by adding email addresses without the owners knowledge. Beware of comments from their website. We are having the Canadian police investigate their website.
I’m amazed, I must say. Seldom do I encounter a blog that’s both equally educative and
entertaining, and without a doubt, you have hit the nail on the head.
The issue is something too few folks are speaking intelligently about.
Now i’m very happy I stumbled across this during myy search ffor something relating to this.