Using RS Steam for Tesla Turbine

Hello. My husband and I have been reading this site for a while now as we've been designing the remodel of our home in South Dakota. South Dakota has extreme weather in winter and summer - and everything in between. With windchill, we can get down to -40 F at times - and lower in the winter to a heat index feeling of over 120 degrees F at times (not consistently though).

As far as we know, nobody is doing what we are doing in this area - nor have they ever tried. Here's what we are trying to do:

1.) Building the interior of our home with adobe brick that we make ourselves using our kiln (bricks rated for 3000 degrees F).
2.) Making our own adobe shingles coated with a special glaze over the top to assist us in our rainwater harvesting.
3.) Making our own floor tiles out of ceramic
4.) Making an entire kitchen out of a rocket stove mass thermal heating design that conjoins into a "heater" going into two other rooms.

In a nutshell - anyway. There's a lot of things (as many of you know) that will have to be done as well.

So here's the catch.

We've been looking into wind turbines to go completely "off grid," however because we know a bit about the tesla turbine, we're thinking that perhaps itching your brains would help us in creating a functional tesla turbine using the steam from the mass thermal heater - the rocket stove to fuel our vertical turbines on top of our home.

Here's what we're thinking - and we'd LOVE your thoughts, please.

We've thought about restricting the very top of the chimney to increase the velocity of the steam in order to turn a turbine fast enough - but that would seem to also restrict draft and become counter productive. Perhaps the addition of a small fan in the chimney and then constricting the top of the chimney to increase velocity would work? The temperature at discharge of the RS is about 90 degrees F - so perhaps reduce the size of the stack to increase the temperate and to increase the force? We've even considered exploring the use of a bi-metallic strip that would rotate because of the difference of the two different metals and their respective responses to heat. Perhaps even small fluctuation in some chemical structure that would generate an electrical current?

Perhaps this is the time to use our "phone a friend" if he or she is an electrical engineer! ha!

Any ideas how we can utilize the steam emanating from the flue in order to operate our wind turbines?

Engineer here for your phone a friend call.

A little bit about steam. The steam that is a change of state from water boiling is present in the exhaust from combustion of materials with water in them. The term steam that is used in connection with a steam engine, or steam turbine is a truncated term for pressurized steam or super heated steam. Frequently these systems run at steam pressures over 60psi, some way over those pressures.

Turbines have to have high pressure steam to do any useful work. A Tesla steam turbine works as high pressure steam creates friction on the boundary layer of the internal plates. All of them that I have seen demonstrated did not do very well on a high torque load such as a generator. I have not seen one that could be used to power a significant generator. In this design, Tesla fell short of what a modern turbine can do with steam. A flash boiler or traditional boiler rely on a closed heated vessel. The water inlet point is effectively closed with a check valve, and water pressure has to exceed steam pressure to enter the system. The steam exit is closed by the load, or restriction that the pressure overcomes. Having a closed vessel allows the steam to be pressurized enough to do the work of spinning a turbine or displacing a piston. A rocket stove is not a closed vessel and if you try to nozzle the exit, you would effectively stop the flow of the gases. A rocket stove is a flow through device, with the engine being combustion heat, and heat transfer. There is simply not enough energy left in the exhaust of an RMH to do any useful electrical generation work.

Any fan put into the system to increase flow will consume more energy than can be imparted from the additional energy created. If this were not the case, you could put a fan in front of your windmill and have perpetual motion.

Stirling engines work off of temperature differential, and are one of my areas of study. I have designed dozens, and have patented a mechanism to make them more efficient, (more on this in the not too distant future, fingers crossed). The temps needed for a Stirling capable of powering a house or multi house generator are in the 1200deg F range. The low temp differential designs are very low power, unless you go really big, and that has a whole host of issues that are currently impractical to overcome.

Bi-metal strips would also require more heat to do effective work, as would any known chemical engine.

Your RMH is going to be doing quite a lot of work already. Work that it is well suited for. IMO, it would be best to optimize your RMH to do the best it can as a heater, and use other technologies to provide for your electrical needs.

Some of us are working hard to develop new and existing technologies to work better and with less input. I am confident, that in time, we will refine systems that will close the gap in costs to compete with and out perform our current power generation grids. It is a dream I have been working on for a very long time, and try to stay plugged into what is happening in the field.

Jamie,

I have also considered generating electricity with an RMH, but only enough to power a fan or two for circulating air across the barrel or improving draft velocity.

I found these:

http://www.tegpower.com/pro4.htm

..but I have yet to try them out.

Chris Burge wrote:Jamie,

I have also considered generating electricity with an RMH, but only enough to power a fan or two for circulating air across the barrel or improving draft velocity.

I found these:

http://www.tegpower.com/pro4.htm

..but I have yet to try them out.

an eco-fan would do the trick if building your own turns out to be too difficult.

If you use electricity to power a fan to increase the speed of the "wind" then use a turbine to capture the "wind" energy(- whats need for draft) then you will lose energy due to conversion loss.

If you look at even a tiny wind turbine with a 20ft diameter it still needs wind at 10miles per hour. So if you are going to cut the diameter by 20 then you will have to increase the wind by 20. How are you going to create that 200 miles per hour wind. That above a CAT5 hurricane, we are talking about tornado force winds.

While I see no problem using a wind turbine for night-time low electricity usage, conjunction with solar for daytime solar panels to power high wattage stuff. You are going to be hard press to go off-grid with just wind.

Shane McKenna wrote:Engineer here for your phone a friend call.

A little bit about steam. The steam that is a change of state from water boiling is present in the exhaust from combustion of materials with water in them. The term steam that is used in connection with a steam engine, or steam turbine is a truncated term for pressurized steam or super heated steam. Frequently these systems run at steam pressures over 60psi, some way over those pressures.

Turbines have to have high pressure steam to do any useful work. A Tesla steam turbine works as high pressure steam creates friction on the boundary layer of the internal plates. All of them that I have seen demonstrated did not do very well on a high torque load such as a generator. I have not seen one that could be used to power a significant generator. In this design, Tesla fell short of what a modern turbine can do with steam. A flash boiler or traditional boiler rely on a closed heated vessel. The water inlet point is effectively closed with a check valve, and water pressure has to exceed steam pressure to enter the system. The steam exit is closed by the load, or restriction that the pressure overcomes. Having a closed vessel allows the steam to be pressurized enough to do the work of spinning a turbine or displacing a piston. A rocket stove is not a closed vessel and if you try to nozzle the exit, you would effectively stop the flow of the gases. A rocket stove is a flow through device, with the engine being combustion heat, and heat transfer. There is simply not enough energy left in the exhaust of an RMH to do any useful electrical generation work.

Any fan put into the system to increase flow will consume more energy than can be imparted from the additional energy created. If this were not the case, you could put a fan in front of your windmill and have perpetual motion.

Stirling engines work off of temperature differential, and are one of my areas of study. I have designed dozens, and have patented a mechanism to make them more efficient, (more on this in the not too distant future, fingers crossed). The temps needed for a Stirling capable of powering a house or multi house generator are in the 1200deg F range. The low temp differential designs are very low power, unless you go really big, and that has a whole host of issues that are currently impractical to overcome.

Bi-metal strips would also require more heat to do effective work, as would any known chemical engine.

Your RMH is going to be doing quite a lot of work already. Work that it is well suited for. IMO, it would be best to optimize your RMH to do the best it can as a heater, and use other technologies to provide for your electrical needs.

Some of us are working hard to develop new and existing technologies to work better and with less input. I am confident, that in time, we will refine systems that will close the gap in costs to compete with and out perform our current power generation grids. It is a dream I have been working on for a very long time, and try to stay plugged into what is happening in the field.

Shane,

Thank you very much for that valuable information and I cannot wait to see what you come up with regarding your patents. Of course, I am working on my PhD - but in Philosophy and soft sciences, not engineering lol.

Here is what I had in mind:



Of course - we understand that this alone won't allow us to go off-grid. We will be having 3 or more flues coming up out of our home when all is said and done. I was actually thinking along the lines of a turbo charger - how it spools and then releases (on a high performance car) - but to catch that amount of built up steam/pressure and then release it, in order to start the magnets and copper interacting with each other when there's no wind.

About 10 miles from us, there is a wind farm. It is very windy where we live - but there are times when there is minimal wind (except for at higher elevations).

Our Rocket stove "kitchen" would be acting as a "kiln" as well - reaching temperatures of up to 3000 degrees F if we got it hot enough - and of course, it takes time to get it that "hot." We had discussed last night - after I made the initial topic here - of perhaps putting the discs (with copper and magnets) on an axle (small) inside of the chimney all the way up and down in order to create at least 110 volts to run the coffee pot, toaster oven and any other small electrical device only - not our entire home using the rocket stove.

However, after reading your response - I was thinking it might be possible to build a rocket stove that would be for the sole purpose of generating electricity using steam. I think it would render a brand new design, but would be worth trying. I do a lot of canning with pressure canners and such - and perhaps it would work if we combined the two methods - using the rocket stove to heat the pressure canner and then using that to generate steam powered electricity using the rainwater harvesting system - much like a water heater ran off of a rocket stove. Here's what started our idea for the rocket stove kitchen:



Would really like your input again - if you get the chance. Of course - these are just ideas, and nothing we're actually attempting quite yet. But then again - that's how all inventions start, right?

S Bengi wrote:If you use electricity to power a fan to increase the speed of the "wind" then use a turbine to capture the "wind" energy(- whats need for draft) then you will lose energy due to conversion loss.

If you look at even a tiny wind turbine with a 20ft diameter it still needs wind at 10miles per hour. So if you are going to cut the diameter by 20 then you will have to increase the wind by 20. How are you going to create that 200 miles per hour wind. That above a CAT5 hurricane, we are talking about tornado force winds.

While I see no problem using a wind turbine for night-time low electricity usage, conjunction with solar for daytime solar panels to power high wattage stuff. You are going to be hard press to go off-grid with just wind.

Hello S Bengi,

Thank you for your comment.

Wind turbines in our area need only 8mph (typical ones) in order to function. Our current average annual wind speed is approximately 9 to 11 mph (depending on the season). Our wind turbines that we will be using will be vertical and will look somewhat like the following, except we will be using the double helix design on the fins instead of a straight concave design:



Using the tesla technology in the first video that I posted to shane - it would only need a "jump" before it ran all on it's own using the reaction between the coils and the magnets and would be quite larger than the one in the video. We would be using pretty expensive bearings to create minimal to no friction.

Solar panels aren't going to do us any good in South Dakota due to the amount of cloud cover that we have unless we were to "crop" them out in the field, which would require a lot of line that is not very cost effective and we couldn't use them in the winter. We have the rare "sunny day" in winter here.

This is why we are brainstorming ways to use wind technology for off-grid living - and it's been done before on wind alone. The cost came into play with the power inverter, batteries and the cable for the guy. Here's what he did:



Although we'd be doing ours a bit differently, creating a "wind crop" in our fields and on top of our barns by connecting them all (linking them) and then running a short cord from the top of our home to the battery box and electrical units.

The purpose of our idea using the rocket stove as a "jump" for the turbines on top of our home - would serve as a "backup" generator.

Chris Burge wrote:Jamie,

I have also considered generating electricity with an RMH, but only enough to power a fan or two for circulating air across the barrel or improving draft velocity.

I found these:

http://www.tegpower.com/pro4.htm

..but I have yet to try them out.

Hello Chris.

Thank you so much for the link. Checking it out - and will get back to you.

Found this on youtube -



It wouldn't be hard to use the Peltier Module on our ceiling (especially during winter) because there would be the very cold air above and hot air from below to operate and produce electricity.

OR

We could use it on the chimney of the rocket stoves in our home to produce electricity due to the extreme temperature differences in winter.

Any thoughts?

tel jetson wrote:
an eco-fan would do the trick if building your own turns out to be too difficult.

eco-fans are prohibitively expensive compared to a $20 TEG and some spare junk-- as far as my application would be concerned.

difficulty is in the eye of the beholder.

for jamie's needs, however, using TEGs to generate enough electricity for household purposes, could cost as much as a wind turbine-- but the times at which the system would generate power would be at the discretion of the user rather than at the whim of the wind.

Hello this is actually my first post I know this is about an RMH conversion into a generator but have you ever considered making an exercise bike which could be geared up based on your physical ability to achieve an output of around 3-7,000 rpms you then attach the chain to idk like four 18v truck alternators set up your battery bank so that the four alternators are plugged in to different cells equal distances from each other to help with wear and tear hope this was helpful and I would appreciate input from anyone who might have tried such a contraption thank you and have a wonderful day

josh richardson wrote:Hello this is actually my first post I know this is about an RMH conversion into a generator but have you ever considered making an exercise bike which could be geared up based on your physical ability to achieve an output of around 3-7,000 rpms you then attach the chain to idk like four 18v truck alternators set up your battery bank so that the four alternators are plugged in to different cells equal distances from each other to help with wear and tear hope this was helpful and I would appreciate input from anyone who might have tried such a contraption thank you and have a wonderful day

Even trying to power 1 alternator is more of a workout than most people can handle.  The average person can produce about 100 watts for an hour or so, if you're VERY strong and athletic, maybe 200 watts, if you're Lance Armstrong, then around 275 watts for a few hours.

A single automobile alternator can easily put out over 2,000 watts.

The other problem with converting the pedaling motion to electricity, using an car/truck alternator, is that auto alternators are not very efficient.  You'll typically lose 40-50% of your energy in the process.  In order produce 2,000 watts of electricity, you need 3,000 watts or more of mechanical input power (about 4 Horse Power).  The less power they are putting out, the worse their efficiency gets.  Plus you lose power in the belts that drive it, etc.

So the 100 watts you started out with is now maybe 50 watts.  Using more than one alternator actually makes the efficiency worse, so you end up wasting more energy.  With 4 alternators you'd be lucky to get 20 watts out of it, might end up getting nothing.

It's a good way to stay in shape, especially during the winter time when you might not want to be out side, but it's not a great way to produce much power.
Note: a side benefit of riding a pedal powered generator during the winter is that you'll put off a lot of heat.  Typically 3-4x as much energy as heat and you produce pedaling the bike.  I.e. if you produce 100 watts pedaling, you'll also produce around 300-400 watts of heat, and moisture (sweat), house tend to have low humidity during the winter so the extra moisture is also helpful..

Jamie Corne wrote:
Wind turbines in our area need only 8mph (typical ones) in order to function.  Our current average annual wind speed is approximately 9 to 11 mph (depending on the season). Our wind turbines that we will be using will be vertical and will look somewhat like the following, except we will be using the double helix design on the fins instead of a straight concave design:

Making a turbine spin, and actually getting power out of it are two very different things.

The power in wind goes up as the square of the wind speed.  There is very little energy in wind blowing at less than 12 mph.  You might be able to get a little energy out of wind blowing at 9-11 mph, but it will likely be only 10 watts or so, probably less.

The same goes for using small turbines.  Small turbines capture less air so they produce a lot less power.  Doubling the diameter of a turbine quadruples the output power.
Lots of small turbines cost more and produce less power than 1 larger turbine.
If you're going to put up a turbine, shoot for a minimum size of 16 feet in diameter, and make sure it is at least 50 feet up in the air with no nearby trees or buildings.  Anything smaller won't produce enough energy to pay for the cost of the turbine and tower.

DO NOT mount them on your roof tops, that is a very bad idea.  Not only is the wind chaotic near roofs (which further reduces available power), but the roof acts as a sound board for the turbine and makes them VERY loud.

Solar panels a cheap these days, it might be cheaper to put up 10x as many panels as people do in other areas, than trying to install a 16-20 foot turbine.  Even on cloudy days my panels still produce about 10% of the power they produce on clear days.  In the 8 years my panels have been up I've had 1 day when their output dropped to 5%.
Lots of solar panels and a battery bank that is large enough to power your house for 3-4 days usually works even in areas without lots of sunshine.

Jamie Corne wrote:
It wouldn't be hard to use the Peltier Module on our ceiling (especially during winter) because there would be the very cold air above and hot air from below to operate and produce electricity.

OR

We could use it on the chimney of the rocket stoves in our home to produce electricity due to the extreme temperature differences in winter.

Any thoughts?

If the rocket stove is well designed, then the air in the chimney won't be super hot, the whole point of a rocket stove is to extract as much heat as possible before exhausting the smoke outside.

You'd get better output by mounting the Peltier (technically a Seebeck or TEG) module on the stove.  But a TEG(Thermal Electric Generator) is still an expensive way to generate electricity.  Even solar panels on a cloudy day would produce more power for less money.