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All the drawings/plans here are the end result of me trying to figure out how I can add some wind power alternative energy resources to my home and workshop while living in a subdivision.
 Scaled up, this could also be the basic power and hot water for a small home or maybe a vaction cabin in the woods somewhere.   These are not what you normally see when looking for wind and solar power!

   I have two major drawbacks implementing any wind power idea in my area though.

#1   Our average wind speed around here is Wilmington , North Carolina is only about 10-15  mph although because we are on the coast we do normally get the daily "to and from" winds from the ocean. 

#2    I can't put up any kind of tower more than a few feet above my house's roof level because the lot is far too small, too many electrical wires and local zoning. 


Wind and solar

                               Micro-Tide system 4  ver. 03 

This is the third version of the 'Micro-Tide' system 4 .  This is a low power system that would generate about 400 watts max at 12 volts dc. Unlike that last systems this uses compressed air supplied by one or more wind turbine driven air compressors.  It uses solenoid control valve on the hydraulic motor also that will allow the system to build up to maximum pressure before it  starts each run cycle.
    At the end of each cycle this uses the compressed air left in the pump tank to  pump the water back into the other empty pump tank. The piston pump uses a larger  pumping piston than power piston in this setup so no air should need to be supplied by the main air tanks. They can be refilling for the next generating cycle while the drain tank is being pumped.


Wind and solar

                               Micro-Tide system 4  ver. 02

 This is the second version of the 'Micro-Tide' system 4 .  This is a low power system that would generate about 400 watts max at 12 volts dc. Unlike that last systems this uses compressed air supplied by one or more wind turbine driven air compressors.  It uses solenoid control valve on the hydraulic motor also that will allow the system to build up to maximum pressure before it  starts each run cycle.
    At the end of each cycle this uses the compressed air left in the pump tanks to pump the water back into the tanks. The piston pump uses a smaller pumping piston than power piston which allows it to pump against it's own operating pressure.  It will still have to be supplemented from the main air tanks toward the end of the operation but this uses less air than pumping directly with the main air tanks so it is a little more efficient.


Wind and solar

                          Micro-Tide system 4  ver. 01

This is the first version of the 'Micro-Tide' system 4 .  This is a low power system that would generate about 400 watts max at 12 volts dc. Unlike that last systems this uses compressed air supplied by one or more wind turbine driven air compressors.  It uses solenoid control valve on the hydraulic motor also that will allow the system to build up to maximum pressure before it  starts each run cycle.
    At the end of each cycle this system instead of bleeding the higher psi gas from one set of tanks to the other set this layout sends it though a sealed air motor that turns another alternator that allows more generating capability from the system



                         Different Mini Power Plant  (basic setup)

This is an alternative version of the system above. The difference is this setup is purely mechanical.  The air motor is turned on an off with control valves operated by the inlet air pressure.   It is designed to turn on at approximately  125 psi and turn off approximately 40 psi.

The second pic is an enlarged view of the control valves so the operation can be plainly seen.



           Water pump operated by small air compressor
                       turned with windmill blades


This is a simple little pump with only 3 moving parts.  A piston, piston return spring and exhaust piston/valve.  The theory of operation is very simple. A small air compressor such as you get a any 'large-mart' that runs on 12 volts from your battery is dissassembled and the little electric motor exchanged for windmill blades. It is then mounted on a frame and put on the top of a pole!. 

 The small air compressors are generally rated as much as 250 psi but that will not be needed here.  

 The pump is actually capable of working with the full output pressure of the compressor and pump water pretty high up if needed though - the pump would have to be built out of all metal for reliability though I think in that case... I plan to use pvc pipe and only about 10 psi output presure maximum.
  
  The operation of the pump is very simple. 

  1)   The air from the compressor is fed on top of the piston forcing it down and pumping the water out.
        As the piston reaches the bottom some of the compressed air is bled into the exhaust pressure
        system tank.

 2)  The exhaust delay valve is prevents the pressure from acting on top of the exhaust piston/valve
        untill the pressure tank has time to build up. 

 3)  The pressure on the exhaust piston builds up and forces the exhaust valve open and vents off the
       piston pressure.  It doesn't have to move much as the exhaust valve is large compared to the
       cylinder/piston  diameter. 

 4) The piston return spring to raises the piston back up refilling the pump casing with water.  As the
      piston reaches the top, the bleed off valve  that has slowly been allowing the exhaust psi to bleed
      away the whole time pressure has been in the exhaust psi tank  finally allows the exhaust return
      spring to close the valve and start the cycle all over again

 
    The bleed off valve should be adjusted open just enough to operate the exhaust valve properly. This will allow some pressure will remain in the exhaust pressure system once the pump starts operating if the there is enough compressed air supply.  This "left-over" pressure will allow the pump to run at a slightly faster pace as it take less each time to refill the exhaust pressure system each pump stroke.

 
The compressor will be supplying air pressure the whole time but since it is supplied fairly slowly and the exhaust valve is large, it has essentially no effect on the system when the piston air is exhausted in the cycle.

  The exhaust delay valve should also be adjusted to to allow the faster operating speed possible for the amount of compressed air supplied.   Orifices could be used instead of valves and a table built up to match various air supply capabilities but valves are simpler and quicker to set.



AIR 1.GIF

     A WIND POWERED HIGH AND LOW PRESSURE AIR COMPRESSOR 

  THEORY OF OPERATION:   The water from windmill driven pressure washer pump will be used to displace air from an upturned nitrogen bottle.   When the bottle reaches a certain weight (bottle almost full -almost all air forced out), the air powered controller will stop the water input to the bottle and allow the input to go to atmospheric psi allowing the water to drain back into the tank (pump will be bypassing at this time directy back to tank).

   When weight drops to certain point on the bottle the controller will again allow water back into the bottle.    This will continue untill the bank of hp tanks reaches approx. 1500 psi and then the controller will simply use the 125 psi air and an air powered disk brake to stop the rotor and pump.

  At 1200 psi the controller will release the rotor and the process will start all over.  Air from the HP tanks will go through a reducer to 125 psi and fill main use tank. The HP air could also be used for filling paint ball marker tanks if you are into that. LP Air can then be used for whatever needed.

 This is not a high capacity flow system but since it would be fully automatic and can fill when ever there is wind day or night it would be cheap source of air to use .

  I had thought about using a small hydraulic pump as it would be able to do other stuff too but I don't think I want the fluid at 1200- 1500 psi in contact with air (the system will be slow enough that heat generation wouldn't be a problem but I don't see any point in taking the risk of a possible fire or explosion due to some sort of compression effect.
See the
Mini power plant  page for more info on this idea       


Alternator and Generator Information

Alternators / Generators

 There are many different routes that can be taken here. A simple car alternator will work just fine if the gear ratio to the air motor is set up correctly.  A car alternator would require a larger motor though.
 
 Another alternative is to use an electric motor as a generator like alot of the small windmill builders do. This type setup could be matched to the air motor available fairly easily as there are a large number of different size motors that can be used.  

 And then for the builders of the group a hand built alternator of the windmill type that uses a car wheel brake disk setup or something mechanically close to them with large magnets and hand wound coils.   This setup gives the most capability to match the air motor or windmill blades as this style can be scaled up or down as needed.

  These sites below give almost all the info you might need on how to build an alternator or generator by hand. They are designed primarily to be operated by windmill blades but can be driven by any motive force. You can also learn how to make the windmill blades on these sites.  It's alot easier that you might think!

  Voltage and current outputs of these handmade alternator are generaly as higher than any premade for the same price (if you can even find one priced that low - The cost of building one of the disk brake designs is less than $300 unless you are designing something really big.  Normally the magnets are the biggest cost but the price of copper has gone way up lately so they are getting a little more costly to build. That is still far below the normal retail of a commercially made equivalent output model though.    You don't need a machine shop to build  them either which is another nice plus.    They also show some of the various small motors that are commonly used as generator / alternators.

                                     http://www.otherpower.com
                                     http://www.scoraigwind.com/index.htm