TRUE sustainable electricity?

Hello everyone, I am new here. I have enjoyed reading everyone's comments. I am planning to build a yurt and would like to have electricity that is not derived from fossil fuels.  Does anyone have experience with magnetic generators?

Thanks

Aren't all electricity generators magnetic?

ntrgrl5 wrote:
Hello everyone, I am new here. I have enjoyed reading everyone's comments. I am planning to build a yurt and would like to have electricity that is not derived from fossil fuels.  Does anyone have experience with magnetic generators?

Thanks

Most generators use magnetic principles. From the ones on peoples cars to magnetos on motorcycles, to hydro plants, to the diesel gensets. The difference from fossil fuel to not is how it gets turned... it can be turned by hydro (the sun moves the water of course so maybe it is nuclear powered?), it can be turned by steam through a turbine, or steam engine... with the steam being generated by wood (sun energy), fossil fuels (sun energy), or focused solar radiation (the sun again). Or a heat engine heated by the same three methods (I have left out direct nuclear power as both not safe and economical and also too close to where I live.... 14 light minutes is a good distance thanks)

Basically it all comes from the sun. The generator part is the easy part... easy to build from old microwave oven magnets... use an AC motor... there are lots of 4k gas driven gensets for less than $500 on sale.. or less if used, and the motor would wear out before the generator... one could probably sell the motor anyway and then the generator is left with all the wiring complete with breakers and outlets. The one I have sitting here is either two 120v plugs or one 240v plug... some come with a 12v dc outlet too. If 12v DC is wanted... the used car/truck parts place is where it will be found as an alternator. The ones from the diesel pickups give over 100A... more than one can be connected to the same drive shaft for more output/redundancy. (more powerful ones are available that can do arc welding but they are pricey.)

Turning the shaft is how it becomes fossil or not. The general preference is hydro if running water is available.... anything else starts expensive and goes up. The least expensive is probably to use a gasoline genset with a wood gasifier.... depending on the availability of wood. Natural gas from manure would work too, but requires daily attention as well as a good source manure. Both will also give a source of heat... if wanted or not... it can be used to heat water for washing or heating a home. The gasifier also gives charcoal.... but the generator will not be running while the charcoal is being emptied or new wood added.

Heat engines require either steam and the knowledge to use it safely, or a sterling engine.... most of the discussion I have heard suggests that solar panels are a better/cheaper way of doing things even with the need for batteries. There has been suggestion of a turbine using a refrigerant (like CO2) that could operate with a hot side of only about 140F and a cold side of 50 to 70F. A normal solar water heating system typically aims for the hot side and the ground under the house would start at about 50F and if warmed to 70F or so, keep the house warm through the winter. Such a system could run 24/7 if the hot water tank was big enough.

Oops, I forgot, wind should probably come after hydro.... well, somewhere up there. To use wind, two things are needed: 1)  wind  2) space to erect a tower (and the permission to do so). These systems also require batteries and the charger is different than the one used for a solar panel so the two can't be combined if using both... two chargers would be required.

So much for that... Yurt? A real Mongolian ger? or a yurt shaped building? Why do I ask? Both would have very different needs for power. The ger would only be looking for light and perhaps entertainment from power... solar panels are the best way to go. The ger is a nomadic dwelling that would only stay in one place 6months at a time... a family would have two for the summer and one in the winter and use the extra felt from the unused ger to help insulate the one in use. The ger is designed for mainly dry climates... not the PNW for example. Yurt shaped buildings are permanent structures which may be bigger in diameter or even have two floors (or a loft). Power would be wanted for a well, lights, entertainment, food preservation.... washing clothes, etc. Two different lifestyles and different power requirements (or wants anyway).

Many people start with a minimum requirement that leaves out some of the big uses like the washing machine and tools. Solar is used for the things that must run all the time like lights and fridge/freezer. Once a week a genset (often fossil fuelled) is run to make sure the batteries are full and equalised and the washing machine is run at that time or tools for wood work or whatever are used. This arrangement allows one to start off with less solar panels or wind generation while not running a genset all the time. Most people start with a genset left over from when they were building their home... they start with the thought that they will not use it any more now that they have solar panels... but find they still need it sometimes to keep their batteries in good shape.

So the first thing is to figure out what the power needs are... and what the wants are.

Hello Len

"There has been suggestion of a turbine using a refrigerant (like CO2) that could operate with a hot side of only about 140F and a cold side of 50 to 70F"

This is Open Technology developed by DaS Energy. The temperatures you quote is the maximum known operating temperture.  A 1 litre turbine rotating at 60 RPM produce 720kw.  However wattge decreases by temperature to its lowest working heat where it produces 720 watts.

Wattage output is calculate for 1 litre of fluid per second at 9 bar pressure produces 720 watts.

Any fluid may be used though DaS Energy chose CO2 for its high energy output at low heat and self cooling upon discharge to holding tank. Operatring gas temperature above 32*C  produces Dry-Ice minus 40*C in the holding tank thus providing excellant cooling without further input.

The device in its entirety is home constructed out of cut and weld of pipe.

http://i1225.photobucket.com/albums/ee397/DaSEnergy/DaSvalve.jpg


Cheers Peter

The magnetic generator I had in mind is one where the polarity of the magnets turn a wheel.  I think it might charge a battery.  No external energy source is involved.  No sun, wind, water...

ntrgrl5 wrote:
The magnetic generator I had in mind is one where the polarity of the magnets turn a wheel.  I think it might charge a battery.  No external energy source is involved.  No sun, wind, water...

Sounds like a "Dire Straits" song I once heard... something about "Money for nothin' and chicks for free". It's kinda funny because performing takes a lot of energy and prep. But I would suggest it was written in fun. The same thing applies here... no input equals no output. Even Tesla's wonder generator that no one has been able to duplicate was conceived as having some source of input. Should someone find a working example of this generator, I am sure there would be a line up to see it. They call them perpetual motion machines.... The ones that seem to work generally are just very good fly wheels... or the input is hidden.

DaS Energy wrote:

This is Open Technology developed by DaS Energy. The temperatures you quote is the maximum known operating temperture.  A 1 litre turbine rotating at 60 RPM produce 720kw.  However wattge decreases by temperature to its lowest working heat where it produces 720 watts.

Yup, that is what I was referring to. I am interested... but my knowledge of the physics involved is not quite there (elecrical, RF, and such are not a problem). I have an understanding why it would work... but the pictures don't tell me enough to actually build one. I think I would be able to figure out the turbine part, but injecting the cold working fluid into the heating "chamber" (my word not sure what it should be called) without the high pressure pushing it backwards is a puzzle to me. (same with a steam engine boiler actually)

Now the idea that 140F is a max temp I am comfortable with. I would assume the power out would be determined by the difference of hot end to cold... however...

Wattage output is calculate for 1 litre of fluid per second at 9 bar pressure produces 720 watts.

The temp difference needs to expand/pressurize the working fluid to at least 9 bar... Ok... the temperature difference being how much to do that? And is the temp. diff. constant over temp.... That is, if I have 100F difference from 40F to 140F is that the same pressure as from 0F to 100F? (phase change is not included)

Any fluid may be used though DaS Energy chose CO2 for its high energy output at low heat and self cooling upon discharge to holding tank. Operatring gas temperature above 32*C  produces Dry-Ice minus 40*C in the holding tank thus providing excellant cooling without further input.

Or are you saying it cools itself? I certainly don't see anyway of keeping the cold end down to -40C as the big heat sink I have is the ground at 50F starting out but rising over time to (hopefully) around 70F. I also can't see how freezing it would help anyway... too hard to move.

The device in its entirety is home constructed out of cut and weld of pipe.

http://i1225.photobucket.com/albums/ee397/DaSEnergy/DaSvalve.jpg

Yup, think I can do that.... my welding would probably require extra grinding as I am just starting/self taught.... Sealing the shaft of the turbine would be my biggest challenge.. though machining could be a problem too (I was thinking to use premade bearing mounts and for the one way valves too).

Anyway, as can be seen, I "get" the idea, I like it too, but I don't have the background to understand reasonable pipe and tube sizing.... reservoir sizes, all the practical stuff. I would be willing to make one... taking pictures along the way... to generate a sort of instruction set for others. In general, the big drawback to using something like a sterling engine for small home use has been cost and design availability. This could perhaps be that missing link for some people. I don't need to make money from it...

Having said all that, if there are some specific areas I should do some self study first... Please point me in the right direction.

Recyclable lead-acid batteries seems acceptable to me, but my bet is the next 10 years result in stunning gains in battery & PV technology that will make home PV systems tied to mostly renewable grid power a reality in a very large number of homes. 

LED lights will take major leaps forward in both cost and brightness. 

Of course, we should be going first after the low-hanging fruit of conservation, passive solar heating, and solar hot water.

Hello Len,
Sorry about the late reply computer went phyist.
There be no injection required the system is gravity flow back from holding tank t to heater pipe.  There be a check valve prior to the the pressure tank preventing any backpressure during refill.  The return liquid Co2 needs be lower temperature than +32*Celius or it will not be liquid.  The power out is defined by the temperature difference between cold an hot.  Sorry cant get the graphs of phase change CO2 Critical and Supercritical across as each time I go to Photobucket this reply gets wiped out.  However the web has many a site on the subject. CO2 is known as an odd gas in a container it bottoms boils at -40* Celisus and if the heating is above +32* Celsius the CO2 turns to Dry-Ice -40* Celsius at the top.  Having the top of the heating pipe in the cooling/collector tank provides excellent cooling.  Only the liquid CO2 moves the Dry-Ice remains in the heating pipe untill its melted by the hot liquid discharge from the the turbine.  Sealing the shaft can use any seal however two ring magnets with face to face polarity provides excellant seals.  Because this model uses only CO2 line pipe is needed for construct, as the pressure is 10,000 bar, though the turbine runner can be made from any grade of pipe.  The turbine in entirety can be made from cut and weld of pipe.  One pipe half the diameter of the other is cut lengthways  to produce turbine vanes, these in odd number are welded to same size pipe.  This fits neatly into pipe of twice the diameter.  Pipe sizing is constant throughout though the pressure contaoner need be at least thrice the volume of the heating pipe. 
Should you wish a turbine of lower pressure need another model uses water cooling and any gas to provide force. This works by gas/fluid dynamics in that hot gas escapes from the turbine runner into the bottom of cooling tank, and water from the cooling tank replaces the hot gasthe gas on the turbine runner, then higher up the water drains back off the turbine runner and is replaced by cool gas which is then progressed to heating point where the gas expands providing drive force.
http://i1225.photobucket.com/albums/ee397/DaSEnergy/RROTARYDAS.jpg

Just have to mention the upcoming possibility (probability?) of home/community electricity generation via fuel cells, using hydrogen that has been hydrolyzed from water, and stored locally/residentially.

Prof Dan Nocera, MIT, has found catalysts that make the hydrolysis easy and cheap, with any water, and powered by solar and wind ... it solves the storage/battery problem.

Of course, fuel cells need cheaper membranes and folks are working on it.

Here he is at PopTech & his new company is Suncatalytix.
http://poptech.org/danielnocera/

and as of 4/2011
http://www.climatecentral.org/blogs/nocera-takes-solar-energy-for-the-masses-one-step-further

Nancy Sutton wrote:
Prof Dan Nocera, MIT, has found catalysts that make the hydrolysis easy and cheap, with any water, and powered by solar and wind ... it solves the storage/battery problem.

But there are water shortage problems all over. I can see this being useful if you are on the coast, but inland? Wouldn't there be negative effects? I imagine doing this on a large scale would further deplete our water resources.

From another website on this 'artificial leaf' technology:

"The gases could be isolated and stored in a fuel cell, which could provide power later and produce pure water as its exhaust."

http://techcrunch.com/2011/09/30/more-details-on-mits-artificial-leaf-and-video/

The article at the website has links to recent article in Science, et al.

Jonathan Byron wrote:Nickel-air batteries are simple and durable. And other battery technologies are being developed.

Solar and wind are variable. But if the solar/wind grid is extended beyond the home or neighborhood, it becomes more stable.

And for long term near lifetime batteries nickel iron "Edison" batteries are even better for fixed low usage systems (expensive and heavy though, you will easily spend $2000 on the batteries that you could buy 'standard' RV batteries equivalent for $500 and they will weigh 4 times as much as well.) But for fixed locations with enough space, and seasonal maintenance (mostly just adding water) these sorts of batteries have lasted 60+ years of near continuous usage.

My dream system uses a waterwheel to drive a 30-70kwh generator intended to be driven by a tractor PTO shaft! Expand on this system and you could conceivably have three phase as well.....this in ideal conditions can run a whole village including pumps for a supplemental closed water loop, eliminating dry season concerns! You could have a full kitchen with electric everything that a chef would drool over and this system will run it. Plus a small walk in fridge (just as an idea the kWh this generator system could produce.

Cons would be extream water drought, size of water wheel, and producing too much would require scheduling "electric time" so as not to speed the wear on the generator head....

I have never shared this with anyone, tell me what I didn't figure out please!!! Interested to hear a wiser perspective

Chadwick Holmes wrote:My dream system uses a waterwheel to drive a 30-70kwh generator

Assuming you mean 30-70kW then you would need a 2.5 metre head of water and a flow rate of 3 metric tonnes of water per second to hit the midpoint of that range.

Not impossible but highly likely to be impractical at the village scale

Leverage of wheel size and shaft work with gear ratio pulleys will account for the water volume, I am in a very hilly wet area....and I have an Amish machinist who does shaft work for shops! He can build in the ratio to spin the head shaft at the required 540 rpm.




Ok, I did some work, yes a 37 foot wheel with crazy gearing would do it, but you are right.....not reasonable......but now I gotta come up with a new dream system.........or a really big wheel!!! Haha

My electricity usage:

Lights. currently old fashioned filament bulbs, gradually replacing with LEDs. Dislike low energy bulbs. A little mercury in my environment is more than I want.

Laptop and phone.

Washing machine. Water heated by solar most of the year. Improved wood fired heating system now in place.

Fridge freezer. Said to be relatively efficient.

A few power tools.

Not using electricity for heating and hot water makes a huge difference.

Electricity bills about 20 euros per month. Wife wants a dishwasher in future. Got a solar panel. It powers batteries, sometimes useful. Getting more of them hasn't been a big priority. Will do one day. The batteries charge controllers etc. each cost equivalent of several months electric. I will probably put higher priority on more batteries than more panels. Power cuts are fairly common here.

A big step forward would be shirts with detachable cuffs and collars, like we used to wear. Before washing machines. I don't enjoy hand washing laundry.

The thing I am watching closely is the Saltwater Battery.  Once these come into full production the solar and wind will be much more worthwhile.  There are several companies working on them right now.

It's in early stages, but the people at Wheaton labs are tinkering with a rocket stove that creates electricity. It's definitely doable, but is it DIY-able? I have seen a commercially available campstove that has usb adapter, so you can charge your phone while cooking your camp dinner. And will enough electricity be generated to be worth the effort? This could be THE all-in-one solution for an off-grid homestead!  See https://permies.com/s/permaculture-technology-jamboree for details and there is a BOGO sale for that event happening NOW! See https://permies.com/s/ptj-bogo-sale

@Len Ovens

Not really sure where you got the idea that electricity is generated by magnets as that is not the case at all. Tiny generators do, but most bigger ones use DC power to make a magnetic field that the generator spins inside of.

It is no different than making a magnet using wire coiled around a nail hooked to a battery. We use 125 volts dc to form a magnetic field to produce ac power. In power generation it is called an exciter and comes on only after the generator is spinning, and then at a certain speed so the frequency is close.

Syncing in, means the generator and the grid become tied together electrically. Typically this is done at 59.5 hertz so that the grid pulls it into speed instead of slowing it down. Once locked it, it will maintain that 60 hertz or go offline.