Tree Wind Generator
in [Design]
|
Prev: madell px3700
Next: Solar cell
From: Paul Keinanen on 17 Apr 2010 02:38 On Fri, 16 Apr 2010 22:34:03 +0100, Dirk Bruere at NeoPax <dirk.bruere(a)gmail.com> wrote: >An idea I've had for years, but never tried and never seen anyone else >do it either. >Simple idea - capture the energy of a tall tree swaying in the wind. >Rough numbers: 200kg force (2kN) through 0.3m every 2 seconds is >potentially around 330W. What kind of trees are you thinking about ? I have wire antennas hanging from pine trees and if the movement and forces would be as large as stated, the antennas would have snapped a long time ago. >Tie a line to the top of the tree to ground via a spring. Use the >movement of the tether to drive a ratchet connected to a generator. > >Anyone know of anything similar? Possibly a usable system to power some flea power meteorological station that transmits the cumulated data a few times a day. For any real power production (e.g. summer cottage) this is unfortunately a bad idea. The kinetic energy of the wind is proportional to the third power of wind speed and directly proportional to the cross section area and air density. While there are quite stable winds above 600 m, the surface roughness will drop the wind speed close to the ground. On a small low island in the middle of a sea or a moderate tower in the middle of a crass land will produce some usable power levels. In areas with trees and bushes within a few kilometer, the wind turbine would have to be well above the tree tops to produce usable levels of power. This tree spring idea was compared to wave power, however, the density of water is about 800 times larger, so the extracted power density would also vary in the same way.
From: TerryKing on 17 Apr 2010 04:42 > I have wire antennas hanging from pine trees and if the movement and forces would be as large as stated, the antennas would have snapped a long time ago. I've had long wire antennas in trees in New England for 50 years. The wind motion WILL snap even strong wires, so there has to be hundreds of pounds of force, at least some of the time. The typical "Solution" is to have one end supported by synthetic rope going through a pulley attached near the top of the tree, and routed down to the ground. A weight of 20 to 50 pounds (Typically a concrete block or two) is attached to the lower end, keeping constant tension on the antenna wire. I've been out in a high wind, checking antennas, and seen those weights move 2 or 3 FEET up and down. So the energy is there. I never tried to USE it :-) How to capture and store it?? A ratchet / generator like those hand- powered flashlights but bigger. (A rotary one-way clutch from an old lawn mover, a drum and a rope?) Or pump water uphill and use it later?? Lots of people will tell you you're crazy. But I have personally adopted this quote from Buckminister Fuller (Inventor of the geodesic dome) since I heard him say it at IBM many years ago: "Dare to be Naive" ! !
From: Paul Keinanen on 17 Apr 2010 06:22 On Sat, 17 Apr 2010 01:42:01 -0700 (PDT), TerryKing <terry(a)terryking.us> wrote: >> I have wire antennas hanging from pine trees and if the movement and forces would be as large as stated, the antennas would have snapped a long time ago. > >I've had long wire antennas in trees in New England for 50 years. >The wind motion WILL snap even strong wires, so there has to be >hundreds of pounds of force, at least some of the time. The question is, how much sag do you accept in calm warm environment ? With sufficient sag, the wire will not snap. I have a multiband inverted-V dipole hanging from the tallest pine tree with the ends of the element suspension wires suspended via other pine tree branches "pulleys" into small trees acting as "springs". Anyway, most of the dipole radiation is created close to the high current point, i.e. close to the dipole feed-point, so the wire sagging does not drop the radiated power in a significant way. >The typical "Solution" is to have one end supported by synthetic rope >going through a pulley attached near the top of the tree, and routed >down to the ground. A weight of 20 to 50 pounds (Typically a concrete >block or two) is attached to the lower end, keeping constant tension >on the antenna wire. > >I've been out in a high wind, checking antennas, and seen those >weights move 2 or 3 FEET up and down. So the energy is there. I >never tried to USE it :-) Thus 10 .. 25 kg and 0.7 .. 1 m with unspecified cycle. The original poster claimed >Simple idea - capture the energy of a tall tree swaying in the wind. >Rough numbers: 200kg force (2kN) through 0.3m every 2 seconds is >potentially around 330W. Thus up to an order of magnitude less and then only during a storm. >How to capture and store it?? A ratchet / generator like those hand- >powered flashlights but bigger. (A rotary one-way clutch from an old >lawn mover, a drum and a rope?) Or pump water uphill and use it >later?? > >Lots of people will tell you you're crazy. But I have personally >adopted this quote from Buckminister Fuller (Inventor of the geodesic >dome) since I heard him say it at IBM many years ago: > >"Dare to be Naive" ! ! Using trees swaying in the wind to produce a small amount of electricity might be an interesting way of powering micro-power electric gadgets and hence very much on topic in this news group. Unfortunately, I have became quite allergic to some "green" claims that if something works in a very specific environment, it will also work for a whole family or solve the national or even global energy needs :-).
From: Dirk Bruere at NeoPax on 17 Apr 2010 10:17 On 17/04/2010 11:22, Paul Keinanen wrote: > On Sat, 17 Apr 2010 01:42:01 -0700 (PDT), TerryKing > <terry(a)terryking.us> wrote: > >>> I have wire antennas hanging from pine trees and if the movement and forces would be as large as stated, the antennas would have snapped a long time ago. >> >> I've had long wire antennas in trees in New England for 50 years. >> The wind motion WILL snap even strong wires, so there has to be >> hundreds of pounds of force, at least some of the time. > > The question is, how much sag do you accept in calm warm environment ? > With sufficient sag, the wire will not snap. > > I have a multiband inverted-V dipole hanging from the tallest pine > tree with the ends of the element suspension wires suspended via other > pine tree branches "pulleys" into small trees acting as "springs". > > Anyway, most of the dipole radiation is created close to the high > current point, i.e. close to the dipole feed-point, so the wire > sagging does not drop the radiated power in a significant way. > >> The typical "Solution" is to have one end supported by synthetic rope >> going through a pulley attached near the top of the tree, and routed >> down to the ground. A weight of 20 to 50 pounds (Typically a concrete >> block or two) is attached to the lower end, keeping constant tension >> on the antenna wire. >> >> I've been out in a high wind, checking antennas, and seen those >> weights move 2 or 3 FEET up and down. So the energy is there. I >> never tried to USE it :-) > > Thus 10 .. 25 kg and 0.7 .. 1 m with unspecified cycle. > > The original poster claimed > >> Simple idea - capture the energy of a tall tree swaying in the wind. >> Rough numbers: 200kg force (2kN) through 0.3m every 2 seconds is >> potentially around 330W. > > Thus up to an order of magnitude less and then only during a storm. Just because the stroke is moving 25kg does not mean that it could not move something 10x heavier. After all, the above poster was adding weight merely to tension his lines. -- Dirk http://www.transcendence.me.uk/ - Transcendence UK http://www.blogtalkradio.com/onetribe - Occult Talk Show
From: Paul Keinanen on 18 Apr 2010 02:03
On Sat, 17 Apr 2010 15:17:39 +0100, Dirk Bruere at NeoPax <dirk.bruere(a)gmail.com> wrote: >On 17/04/2010 11:22, Paul Keinanen wrote: >> On Sat, 17 Apr 2010 01:42:01 -0700 (PDT), TerryKing >> <terry(a)terryking.us> wrote: >> >>>> I have wire antennas hanging from pine trees and if the movement and forces would be as large as stated, the antennas would have snapped a long time ago. >>> >>> I've had long wire antennas in trees in New England for 50 years. >>> The wind motion WILL snap even strong wires, so there has to be >>> hundreds of pounds of force, at least some of the time. >> >> The question is, how much sag do you accept in calm warm environment ? >> With sufficient sag, the wire will not snap. >> >> I have a multiband inverted-V dipole hanging from the tallest pine >> tree with the ends of the element suspension wires suspended via other >> pine tree branches "pulleys" into small trees acting as "springs". >> >> Anyway, most of the dipole radiation is created close to the high >> current point, i.e. close to the dipole feed-point, so the wire >> sagging does not drop the radiated power in a significant way. >> >>> The typical "Solution" is to have one end supported by synthetic rope >>> going through a pulley attached near the top of the tree, and routed >>> down to the ground. A weight of 20 to 50 pounds (Typically a concrete >>> block or two) is attached to the lower end, keeping constant tension >>> on the antenna wire. >>> >>> I've been out in a high wind, checking antennas, and seen those >>> weights move 2 or 3 FEET up and down. So the energy is there. I >>> never tried to USE it :-) >> >> Thus 10 .. 25 kg and 0.7 .. 1 m with unspecified cycle. >> >> The original poster claimed >> >>> Simple idea - capture the energy of a tall tree swaying in the wind. >>> Rough numbers: 200kg force (2kN) through 0.3m every 2 seconds is >>> potentially around 330W. >> >> Thus up to an order of magnitude less and then only during a storm. > >Just because the stroke is moving 25kg does not mean that it could not >move something 10x heavier. >After all, the above poster was adding weight merely to tension his lines. Do you expect that the amplitude of the tree oscillation will remain the same, when you put say, 250 kg hanging from the line ? |