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Windmill with air compressor instead of electric generator

 
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      Has anyone powered their homestead with a windmill and used an air compressor rather than batteries to store that energy?  When pricing out windmill components I quickly realized that the expensive parts are the generator, battery bank and all of the expensive bells and whistles required to control electricity. The actual wind vanes aren't very expensive and they are something that can be manufactured at home.

    Then looking and what I would use the power for I realized that most of this stuff could be run with compressed air. Many power tools use compressed air. Refrigerators and heat pumps can operate as long as there is something to power the compressor. Water pumps, shop tools and just about anything else with the motor can be fitted with an air motor.

    Air compressors aren't picky about speed of rotation and they are much simpler than electric generators. This would allow for the installation of a very simple windmill set up at low cost. A large recycled metal container could store the pressurized air. If this container were buried in gravel its ability to withstand pressure would be greatly increased.

  Air compressors condense water which must be bled off from time to time. I once had a woodworking shop with a 20 gallon air compressor. This shop did not have its own water supply. I brought in my own drinking water and all other water needed in the shop came from the compressor. With an entire household power system run from the compressor system this could amount to many gallons per day depending on humidity levels. If the water is to be saved for irrigation or other purposes the compressor would need to be lubricated with food safe oils.

    In a mountain or desert environment this water gathering ability could be just as valuable as the stored energy.

    When air is compressed and moisture is condensed, quite a bit of heat is produced. The compressor could be cooled with a water jacket which would produce plenty of hot water.

    When air is released from pressure it becomes quite cold and frosting of equipment is common. So rather than adding to your air-conditioning load your refrigerator motor and shop tools work like little air-conditioners.

    Some things must have electricity and this is simple to provide. An air motor can spin a small generator whenever electricity is needed. The flow from a large compressor tank is very steady and predictable. It could be set to produce what is needed plus a little more which would be dumped into a small battery bank. The battery bank would only need to run things like radios and lights since all of the big power users would be run directly from the air motors.
 
                                  
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An interesting approach. Keep us posted.

 
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I gave this some thought a while back. I got hung up on the thought that the wind turbine might be slowed as the pressure increased in the air holding tank. At some point the pressure in the tank would stop the turbine from turning in light winds.

I don't know enough about pneumatics to say for sure that my concern is valid.
 
                                            
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if the pressure stopped the turbine it would be the equivalent of the battery being charged. If you need more pressure you could add a new tank just like if you would add a new battery in an electric setup.
 
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misterinnovation wrote:
if the pressure stopped the turbine it would be the equivalent of the battery being charged. If you need more pressure you could add a new tank just like if you would add a new battery in an electric setup.



Or let some bleed off and charge a battery for lights and soft rock music radios.

can the water be bled out without loosing all the air pressure?
 
Dale Hodgins
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    Water is bled off without loss of air since the spigot is that bottom and water is heavier. This is done regularly with compressors while the tank is full. A belt system could be turned to a lower gear once high pressure is reached. But a better way to deal with over charging is to have a really large tank and always keep it in the 80 to 120 pounds per square inch range. Big tanks like this are available for next to nothing as scrap when service stations replaced their underground tanks. Compressors have blowout valves to prevent over pressurizing.
 
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you might want to rethink using used underground fuel tanks for compressed air. Storage tanks are not designed to handle pressure, but to hold the weight of a liquid. With the amount of surface on a large tank you will need something pretty substantual, probably with domed ends and either fairly thick plate or with some reinforcement. Now if you were to use propane tanks that would be a different story.
kent
 
Dale Hodgins
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      I like the giant propane tanks that you see at service stations. They retire those from time to time and because they are oversize metal their value isn't very high. But any big tank will work if you plant it in the ground and cover the top a few feet deep with gravel. The hazmat companies who deal with these things clean them with hot steam and I've been inside some that didn't even smell like gas. I seen them go for as little as $200 each when metal prices were low. It's worth that much to haul them to the scrapyard so you'd want to contact the hazmat companies directly and have it taken to your location. Dope growers have used these things extensively where I live.

    I suppose for maximum pressurization you'd want to find out how deeply one of these could be buried and plant it just shallower than that. A blowout valve would be advisable. But if you go with a 10,000 gallon tank which is quite common that should be able to absorb plenty of energy and it's not something that's going to get away from you in 5 min.

    My 20 gallon compressor tank was able to store enough air for several minutes worth of power tool use. A tank 500 times that size wouldn't experience the huge swings in air pressure that these small systems do.
 
pollinator
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I've been thinking about this one for some time as well.
It looks like a VERY attractive idea to me..

One thing that interests me is the idea that compressed air returns can be augmented with heat.. How much energy can be returned (to do work) has a lot to do with how much the returning air can be RE-EXPANDED..
Why not use a solar oven setup with thermal mass of some sort and build a booster??
 
Dale Hodgins
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Why not use a solar oven setup with thermal mass of some sort and build a booster??

 
Dale Hodgins
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      Some sort of heater could work but this heat would need to be applied only after the tank reached a certain degree of fullness. If the tank were hot during the filling process it would be more pressurized and therefore work against itself because it would require more energy to push additional air in to it.

    A dual tank system could work. The tank being compressed would be As cool as possible so as to absorb air more easily, while the tank whose pressure is currently in use could be solar heated. The compression process produces heat so it may be possible to use a water jacket around the compressor and transfer that heat to a coil within the fully compressed tank that is in use.

    This might be a lot of pipping for marginal gains. All that extra work is probably better spent creating a larger or additional windmill.
 
Kirk Mobert
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I wouldn't heat the tanks at all.. If anything, it would make sense to cool them as much as possible.
My idea is to heat the air as it flows back out of storage, just before (or just as) it runs into the tool/electrical turbine..

Air nozzles get cold because air NEEDS heat to expand. When you compress air, it gives up heat in order to fit in a smaller space, when air re-expands it draws heat from the environment until it comes into balance with surrounding conditions.

My thought would be to provide MORE heat than is required to reach equilibrium with ambient pressure at ambient temperature.. More heat (difference)=more expansion=more work per (storage) volume..
No?
 
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Brilliant, make it so! 

Could it also be used as a filling station for a compressed air car? 
 
Dale Hodgins
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     I can't see this working very well for a car due to the low energy density of compressed air. At 4500 air has about 1/35 as much energy as is available from gasoline of the same volume. At 100 psi which is easier to obtain from a home system gasoline contains about 1500 times as much energy per liter. So using this very rough guide, if a tank of gas will take your car 500 miles a tank of a similar quantity of compressed air at 100 PSI will take you about one third of a mile. This may be better for a tractor or some other home device which can recharge frequently.
   Quite a few air powered cars have been produced but none have had commercial success so far as I know.
     I can see one use for compressed air with automobiles and that is for regenerative braking. The operator would have the option flipping a switch which would engage a compressor to slow the car down. Then the air motor would be engaged as the car accelerates to blead the tank down.
 
Kirk Mobert
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I've been watching MDI Enterprises website for a number of years now.. They make some exciting claims, I have no idea how far they've actually come with it, their site has been slow to move..

I've noticed that they talk about using burnables to extend range..
VERY interesting.
 
Dale Hodgins
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This little compressor plugs into a cigarette lighter socket. But It's not a flimsy toy. It's heavy like a starter motor. Made in W. Germany, so made before 1989. I have used this to fill an air pig while driving.

In situations where only 12v is available this can still store up power for air equipment that is used infrequently.

It takes 90 seconds to fill a wheelbarrow tire.

By far the cheapest air pig is a truck tire. Watch the max. pressure rating. A fat tractor tire could hold far more air than do most compressor tanks.

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I worked in the petroleum equipment industry for a dozen years and was a certified tank installer and tester. You can not use old fuel storage tanks for the storage of compressed air. Many of these tanks can suffer structural damage or failure at pressures as low as 10 psi or even lower depending upon their condition. This was a regular topic in our safety training and there are plenty of documented fatalities from over pressurizing storage tanks not designed as a pressure vessel. Latent petroleum compounds also pose a serious risk of explosion as it is almost impossible to remove the impregnated petroleum from the tank in a reasonable period of time. A better re-use for these is water storage (after they have been cleaned and epoxy lined). I like the idea of using compressed air for energy storage but a new unused propane tank would be a better solution provided it was designed for the system pressures and had provisions for removing condensation and inspecting the tank for corrosion.

BE SAFE
 
Dale Hodgins
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Good to know. But if a regular tank were burried under 10 ft. of gravel, wouldn't that prevent bulging and rupturing? Not that i'm going to rush out and do it, just wondering. The cost of burial might be better spent on a pressure vessel. Add to that the cost of my burial and the proper tank seems like an even better idea.
 
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I think you'll find significant losses in an air system compared to electricity. battery storage would be smaller for the same amount of energy.
 
Kirk Mobert
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The way that strain builds on a larger tank versus a smaller one (at the same pressure) is important to note.
It would be better to use more, smaller tanks, or even a spaghetti of tubes. I know, then there is the issue of added joints.
Still, it would be MUCH safer to store pressurized air in a (large) array of pipes (even PVC) than a tank of similar volume.
 
Kirk Mobert
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Abe Connally wrote:I think you'll find significant losses in an air system compared to electricity. battery storage would be smaller for the same amount of energy.



Maybe.. Though batteries are the weakest link of any off grid system. They're also an environmental disaster.
It would be nice to find a suitable alternative.
 
Dale Hodgins
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Auto repair shops use air for many of their tools. I would venture that the power and safety of air systems and the large array of professional grade tools available are why they choose air over electric impact wrenches and such.

Any heavy equipment mechanics care to enlighten this debate.

Would my big tire as tank idea produce usable pressure range or do I need higher pressure than a tire can safely store ?
 
kent smith
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Dale, as far as storage why not buy a couple of used 500 gallon propane tanks. They are rated and tested pressure vessels. I use compressed air in my shop, but know that it is an expensive energy source in regards to running a large compresser. I realize that this is not an issue with what you are proposing. I have thought similar ideas as you. We have a small creek with a very low head across our pasture and some where down the road in my dreams I want to build a water driven shop. I had thought that when I did not need the water power for the machine tools that I would compress air for hand tools. In my current shop I use the air for things like operating cylinders die grinders, DA sanders and misters for cutting toosl rather than ratchets and impacts. I love using the air tools I have, but don't like hearing the compresser cycle on, it sounds like dollar bills flying away.
kent
 
Abe Connally
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Kirk Mobert wrote:They're also an environmental disaster.
It would be nice to find a suitable alternative.



Lead-acid batteries can and are recycled indefinitely.
 
Abe Connally
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Kirk Mobert wrote:The way that strain builds on a larger tank versus a smaller one (at the same pressure) is important to note.
It would be better to use more, smaller tanks, or even a spaghetti of tubes. I know, then there is the issue of added joints.
Still, it would be MUCH safer to store pressurized air in a (large) array of pipes (even PVC) than a tank of similar volume.


more joints = more failure points

storing air at 150 psi is not that dangerous if you don't move the tank much
 
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I would like to start by saying I have no experience in this area at all.

I do however vaguely remember seeing a documentary or something about living off the grid where they used a similar idea. I'm pretty sure one of there main uses for the compressed air was for both heating and refrigeration by means of one of these Vortex tube's

Just thought I would throw that in .
 
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I want a wind powered air compressor. Can anyone provide me some information about this? Looking forward for your reply.
 
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www.windcompressor.com The unit I bought will pump up to 30 CFM at 175 PSI. works great
 
Dale Hodgins
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Seems to be legit. I can only imagine the brilliance of a man who would come up with this. http://windcompressor.com/ I googled things a few different ways when this thread was first posted. Looks like they've done all the heavy lifting.
 
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I've been looking into steam engines and gasifiers. They work to charge a battery bank, but it takes 4-6 hours and you need to actively run the engine as the batteries charge. (Batteries can accept only so much energy each hour without damaging them) So, I thought of using these engines to compress air. It wouldn't take more than an hour to fill a big air tank with an engine-powered compressor, would it? That doesn't seem too bad a run time for a steam engine or gasifier.

The air would run a pneumatic motor, which would run a generator that charges a battery bank. Couldn't I start the pneumatic motor and walk away while it charges the batteries? No danger in that, is there?

Run steam engine or gasifier for an hour or so, then shut it down and start the air motor and go do something else while the batteries charge.

The steam engine or gasifier can be fueled from a wide variety of cheap waste products, so I'm not too worried about the extra fuel required to cover the energy conversions.

The other thing I like is all the other items that can be run off the compressed air. Flexibility is always nice.

Thoughts.
 
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Bill Bianchi wrote:I've been looking into steam engines and gasifiers. They work to charge a battery bank, but it takes 4-6 hours and you need to actively run the engine as the batteries charge. (Batteries can accept only so much energy each hour without damaging them) So, I thought of using these engines to compress air. It wouldn't take more than an hour to fill a big air tank with an engine-powered compressor, would it? That doesn't seem too bad a run time for a steam engine or gasifier.

The air would run a pneumatic motor, which would run a generator that charges a battery bank. Couldn't I start the pneumatic motor and walk away while it charges the batteries? No danger in that, is there?

Run steam engine or gasifier for an hour or so, then shut it down and start the air motor and go do something else while the batteries charge.

The steam engine or gasifier can be fueled from a wide variety of cheap waste products, so I'm not too worried about the extra fuel required to cover the energy conversions.

The other thing I like is all the other items that can be run off the compressed air. Flexibility is always nice.

Thoughts.



My thoughts are that having to maintain and generate (i.e. convert) energy through additional components would raise costs and lower efficiencies. The air compressor and air tank required for such a system would be quite large (and expensive), and it's very difficult to get high efficiency in air compressors and air motors. Besides, the air engine required for battery charging still has to operate for the extended period that would otherwise be required for the gas engine or steam engine. So, it seems there are only disadvantages here. I know you mentioned that you're not worried about extra fuel consumption, but in my opinion this should be a serious concern as this configuration is likely to double fuel consumption with the losses in air compression and air expansion in the engine.

A wood gasifier can be devised to operate at low power levels for extended periods, but there has not been good success here on anything but charcoal fuel. However, there is a promising new gasifier called the "Victoria" that might be a solution. It was designed specifically for this purpose. You can find some discussion on it at the driveonwood.com forums. This product will be sold at a brand new site called www.offgridpro.com. There is also a smaller gasifier called "Anastasia" suitable for 1-2 hp gas engines. The gasifiers were designed by mechanical engineer Stephen Abbadess over the last 5 years or so (he has a YouTube site at http://www.youtube.com/user/sabbadess... here is another site where the user makes gasifiers based on the Victoria design: http://www.youtube.com/user/tritowns). It seems these units need larger hoppers for longer run times, but from what I've seen of the hearth design I'm optimistic that it can operate cleanly at low power outputs. This is the first gasifier I've seen that shows promise for sustaining very low power from an engine without tar problems. FYI, the general approach used as I understand it at the moment is to direct air nozzles at a downward angle to help minimize fuel bridging (the air blast helps to move the fuel downward), the restriction in the hearth is achieved by a small diameter concentric cylinder which helps with insulating the region in the restriction from heat loss, there is dedicated insulation on the hearth provided (rock wool I believe) to further reduce heat loss from the hearth, and an air nozzle supplies air just above the restriction to combust any tars that survive pyrolysis and combustion. At first I thought the latter idea seemed off because the high volatile content of wood should make it impossible to combust all the tars (excess tars would have to be cracked). However, this approach makes sense because combusting tars at the restriction will not add heat to the wood fuel, but add heat to the charcoal bed. So, excess tars produced by pyrolysis near the nozzles (excess tars that cannot be combusted with air) can be combusted at the lower nozzle without leading to increased tar formation through pyrolsys. It should also help to raise temperature at the charcoal bed for driving reduction (water gas, CO2 reduction to CO, or tar cracking). If the unit can solve the bridging problems associated with small gasifiers, then it seems like a very useful unit.

As far as steam goes, I personally remain convinced that a micro (piston) steam engine at at constant low power with full waste heat recovery, and supplemented with solar photovoltaics, cannot be beat. This would protect a modest battery from excessive discharge, provide all heat required for a home, provide enough electricity to power essential loads during inclimate weather (no solar or wind available), and use the widest range of biomass with the least processing required. By contrast, a small wood gas engine system requires careful processing of the fuel (regular small size), cannot use many sources of biomass efficiently, and it's very hard to harvest all the heat from the system. While a very small system would see more than twice the thermal efficiency of a good steam system, a small off grid home simply does not require a great deal of electricity. So, additional electricity can be had from photovoltaics and/or wind systems that consume no fuel.
 
Bill Bianchi
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That's quite a bit to consider. I see what you mean about losing energy in the conversion. It's just difficult to turn away from the convienience compressed air is capable of providing. You mentioned the cost of a big enough air tank, air motor, and compressor. That would be a big concern to consumers. Maybe it's just too expensive.

You mentioned the air motor having to run just as long as a steam engine or gasifier. That's true, but the air motor can run by itself without supervision or having to actively run it. That's the convienience I'm referring to.

A steam engine would probably be best for a number of reasons, but not many people would be willing to stand there running one for the 4-6 hours it takes to charge a battery bank. Possibly, some would be willing to run one for an hour or so while it compressed a tank of air, after which they would start the air motor and go do something else with the remaining 3-5 hours they would have spent running the steam engine while the batteries charge.

I'll look up that gasifier you mentioned. I'd like to see how they stored & delivered enough fuel to run independantly for however long it runs before needing refueling.

As for the steam engine operating on a wider variety of fuels than a gasifier, well, I'm trying to change that with the rocket stove gasifier. . We've made some progress, but still have a ways to go. I'm optimistic, though. I'm hoping to turn waste that would go into a landfill into a source of cheap energy. Doubt it is a solution for everyone, but it would highlight what could be done on a larger scale to greatly reduce the amount of waste going into our landfills.
(We bury our trash and dig up coal. We put one source of energy into the ground, then take a different source of energy out of the ground. How efficient is that?)

If not compressed air, then perhaps some way to store enough producer gas to operate a generator for the time needed to charge a battery bank. If that much producer gas could be stored, you could spend a shorter period of time producing & storing the gas, then run the generator later off the stored gas, without supervising it or having to come back to refuel it.

Maybe we should replicate one of the working magnet motors out there and be done with it. Or take our cue from Tesla and set up radiant energy antennas to run our homes. Or look further into the hydro vortex turbines. Or reproduce the GEET system. Or replicate some of the Lintzless generators.

There has to be some way to run a generator off renewable energy without having to supervise it while it runs, some compromise between efficiency and convenience that doesn't involve fossil fuel from the energy bandits, oops, I mean energy providers.
 
Marcos Buenijo
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Bill, the air tank would be too large and too expensive to store a useful amount of energy for this application. Also, the amount of fuel consumed would be ridiculous.

There is no reason whatever that a small steam engine cannot be devised to operate unattended, and do so safely. The same applies to wood gas (All Power Labs is doing it today, although their system cannot achieve a low power efficiently). I prefer steam for its wider fuel capacity, less fuel processing, and superior heat recovery.

Storing producer gas can be done in principle, but the energy density is so low that it would take a helluvalotta gas. Compressing it is a bad idea.

I've seen no credible evidence that magnet motors work, and the other devices you listed are also dubious (if not outright fraudulent, then they are not cost effective... including Tesla's idea). These are either fantasy or not practical.

If you consider what the energy "bandits" provide, then you must admit that it's an incredibly good deal. After all, think about what an individual must do in the off grid setting to provide the same amount of useful energy. For this reason I say alternative energy is almost never economical when grid electricity is available. I restrict my considerations to the off grid setting for this reason.

 
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Abe Connally wrote:

Kirk Mobert wrote:They're also an environmental disaster.
It would be nice to find a suitable alternative.



Lead-acid batteries can and are recycled indefinitely.



People tend to ignore the very real possibility that things we think of as ordinary and "easy to do" today may not always be possible or practical at a point later in the future. It's irresponsible and myopic not to prepare, or at least consider preparing for exigent circumstances.

Unless you know of some way for consumer-level users to indefinitely recycle lead-acid batteries, I agree with Kirk, they are a potential environmental disaster, and we [permie energy enthusiasts] need to experiment with other solutions for energy storage and use. Growing a sizable community of food-, water-, and energy-independent people is the only chance we have to take back control of our lives, and our civilization. Democracy is on its last legs.
 
Augustus Clark
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Marcos Buenijo wrote:If you consider what the energy "bandits" provide, then you must admit that it's an incredibly good deal. After all, think about what an individual must do in the off grid setting to provide the same amount of useful energy. For this reason I say alternative energy is almost never economical when grid electricity is available. I restrict my considerations to the off grid setting for this reason.



Although on the surface, you are right about grid energy appearing to be more economical, that's because almost all of the cost of the negative externalities associated with fossil fuel extraction, transportation, processing and use are borne by society at large, and not factored into the nominal cost. And fossil fuel companies tend to enjoy very favorable tax situations and subsidies, at least in The United States. So while it's usually cheaper if you compare your electric bill to the cost of a renewable setup, the number on your bill is an illusion. And there are no free lunches in nature; eventually, everything will even out. Furthermore, if one considers decades of payments for energy use versus the averaged cost of purchase and maintenance of one's own means of energy production, the numbers tend to come much closer to evening out.
 
Marcos Buenijo
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Matthew Clark wrote:Although on the surface, you are right about grid energy appearing to be more economical, that's because almost all of the cost of the negative externalities associated with fossil fuel extraction, transportation, processing and use are borne by society at large, and not factored into the nominal cost. And fossil fuel companies tend to enjoy very favorable tax situations and subsidies, at least in The United States. So while it's usually cheaper if you compare your electric bill to the cost of a renewable setup, the number on your bill is an illusion. And there are no free lunches in nature; eventually, everything will even out. Furthermore, if one considers decades of payments for energy use versus the averaged cost of purchase and maintenance of one's own means of energy production, the numbers tend to come much closer to evening out.



I agree in general. In fact, I've done a great deal of study on economics, and I've become convinced that a source of many of the problems seen today stem from the inability for a manipulated currency to generate meaningful money prices. A distorted price structure results that in turn leads to perverse incentives. Prices no longer serve as meaningful proxies for the underlying realities of resource scarcities and the values of market participants. The result is an inefficient allocation of capital, and the effects of this process over time are cumulative. The net result is recurring economic and financial upheavals of escalating frequency and severity, and increasing incentives for war and all manner of imaginative government interventions to stave off collapse. A good metaphor I've considered for this process is keeping a nuclear power plant operating with all the monitoring equipment and feedback control inputs uncalibrated. The entire system only gets progressively unstable as operators make poor decisions based on the faulty readings and control circuits have to be circumvented to keep things going.

No doubt energy would be more expensive after accounting for the hidden and shifted costs involved. However, nobody knows what these true costs may be. For example, some argue that "climate change" is caused by the use of fossil fuels and that the costs resulting from this will far outweigh any benefits. Well, how do these people know this? Answer: they don't. They're talking gibberish. Maybe "climate change" will turn out to be a net benefit. How do we know "climate change" will be a net benefit? Answer: we don't. I do know that the current economic/financial system is corrupt and unstable (and it's NOT capitalism). I also know that trying to provide an off grid home with energy at the same rate consumed by the average U.S. home is far too costly for most settings.
 
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Dale,

Back in the '70's or '80's, iirc, the local Chevron refinery built an earth sheltered propane storage facility using an immense bladder tank surrounded by a large berm and covered with a thick layer of dirt and gravel. I have considered something like it as a large air battery. Unfortunately, I have been unable to find any literature about it to verify my recollections.

The weight of the dirt cover would also provide a constant pressure, like the weight on an organ reservoir.
 
Dale Hodgins
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Andrew Parker wrote:Dale,

Back in the '70's or '80's, iirc, the local Chevron refinery built an earth sheltered propane storage facility using an immense bladder tank surrounded by a large berm and covered with a thick layer of dirt and gravel. I have considered something like it as a large air battery. Unfortunately, I have been unable to find any literature about it to verify my recollections.

The weight of the dirt cover would also provide a constant pressure, like the weight on an organ reservoir.



In order to prevent membrane puncture, the air bladder could be at the bottom of a pond. Anchorage would be an issue and pond level would be altered by the working volume differential. Big jigging hooks should be banned in this pond.

Natural reservoirs for natural gas are used for seasonal storage. These are mostly exhausted gas wells but aquifers and salt caverns can also be used. Depending on the volume of the well chosen, it may take a couple centuries to get the pressure up to a usable pressure. Storage in geologic formations is a realistic option for commercial wind farms and would help to solve peak load issues.
 
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Back in the 1970's Terry Miller came up with an air powered car. He called it air car one and published his designs. He was also quoted saying he could power his air car from a windmill. I am still looking for that design. I am not sure if he built one or not.

Here is a link to the history of air cars . They were resourceful at storing up air.
 
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I have some Knowledge in this area. There is a specific type of Chop Shop operations that hire Professional Car Thieves to steal cars to order,year,color,
make and accessories ! after the car is taken,a quick meeting in an out of the way area is arranged !

When the Car thief arrives he is met by a large Van, the chop shop crew and the car is quickly striped! Air powered tools have been used for this jobs since
I first learned of this in the 60s, Today the only people not using air tools to strip cars are Crack heads/Copper Thieves! This is truly working off of the grid!

The van contains a group of 'K' sized 4500 p.s.i. Compressed gas tanks N2 or Co2, to spin customized Air wrenches at high speed, high torque - If there was
a better system these guys would have it !

Our local Fire Department uses Exactly the same equipment to refill our Self Contained Breathing Apparatus - S.C.B.A.s ether on scene or back at our station,

When the boys jump over the Pit wall to change all four tires in under 12 seconds they use the same extreme Pressure tanks and Customized air wrenches to
spin at high speeds

There is only so much energy that can be stored and used at low pressures. Any problems with any of this equipment must be left to professionals with the
right equipment !

If I had a dc power source from a windmill say I would store my power in dc and
use portable 24 volt (or higher)

For our future, Big Al ! - As always, your Questions and Comments are solicited and are Welcome !
 
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