WIND POWER, WIND TURBINES, GREEN ENERGY FROM
WIND ENERGY, D.I.Y. + INSTALLATION GUIDE.
video clips of my chassis and experimental types
http://www.youtube.com/user/wind4watts
THIS PAGE IS PRIMARILY FOR NEWCOMERS TO WIND POWER.
If you are considering installing a wind turbine or wind turbines, try and make sure that there is a clear aspect from the Westerly side. Most of the British Isles wind comes from the South Westerly direction often swinging from Southwest round to Northwest, so mounting any wind turbine on this side of any airflow obstructions like your home, other houses, tall trees e.t.c. will tend give better results. Ideally wind coming from any direction should of course be utilised to drive your wind turbine where possible. Bungalowed estates, cottages and homes with open areas of land approaching them like farmland or surrounding flat or lower lying ground, do of course have advantages over 2/3 storey urban area as you would imagine.
A turbine with a rotor set and pmg with good low-medium wind characteristics can still be practical in many areas. The air close to ground is riddled with turbulence and eddies as it rushes over and around ground objects, houses fences walls trees e.t.c, getting any turbine a few metres up (as high as is practical), on a mounting pole or post secured to a garage wall, gable end (if a light unit), will increase average windspeed by many mph, and give much improved results. In an ideal world above rooftop level would be ideal though unfortunately this could possibly affect your popularity with the neighbours. Extreemly low wind areas like valleys will not really be suitable for a turbine.
Many larger wind turbines supplied as kits include a tubular tower, one model i had recently included a 6.2 Metre 115mm diameter steel tube tower in two sections with support cables turnbuckles included.
If the wind speed doubles then the energy available goes up by the cube, i.e. by 8 times not x 2, that's why many turbine output graphs start off fairly flat (in lower winds) but rise quite steadily with wind velocity.
Most smaller wind turbines use a tube to hold turbine aloft, and will require the use of 3 or 4 guy cables, (using steel wire "rope") to keep it vertical, and take the strain of wind pressure. Heavier free standing lattice or wide tubular towers can be made with planning and attention to good foundations though would better suit large areas of free space and can be projects in their on right.
Always try and use quite thick ouptput wires from the turbine (adequate to suit amperage of turbine 2-4 square mm) and place your batteries and Inverter reasonably close to the turbine mast in a covered box or in your shed garage perhaps. Lower voltages can suffer from resistance losses, where the power tries to warm the cables especially if too thin, so keeping these fairly close to the turbine means you can run the Inverter output to the house or demand point. The 230v loses very little power as the current in the wire is much lower 1/20th of 12 volt.
At the heart of almost every small or medium size turbine is the pmg permanent magnet generator (or alternator more correctly) , to the laymen this is roughly similar in appearance internally to a large electric motor or alternator , indeed some adapted electric motors like the little Amtek, (lots of information about this on the Web) have been used to build very small but productive wind generators delivering 100+ watts or more, sufficient to charge batteries to power garage eqipment, power tools shed lighting campers tv laptop charger supplies etc, and can often be better than expensive marine types
Guy wires for medium sized home turbines should normally be mounted at (as far as is possible) equidistant angles from the tower, onto either a purpose set concrete foundation, or sometimes into strong brickwork. Cable clamps hold the joints secure, these are available from antenna suppliers or in packets from B&Q warehouses, and i would personally recommend using 2-3 on each joint, as they are THE critical parts!. Turnbuckles are used for final adjustment.
Often some of this equipment will be included in turbine kits. Purpose supplied self assembly tower kits for turbines are available delivered from some U.K. green energy websites . if required.
Heavier tubular free standing towers can be made from steel piping if handy with steel/power tools, and with planning and attention to good foundations , these can be also be purchased in the U.K. from Scottish firms.
Telegraph poles and wooden home built 'tower'mountings have also been used to mount turbines if handy with timber if that could suit location. On a small turbine a thick walled scaffolding tube, U bolted to a solid garden wall or set in concrete may suffice if your not planning to go too high. 12mm stud iron can be shaped in a J or U for this and secured through the wall with nuts & wide washers. It's a good idea to temper the steel once finished though by heating to a straw colour and quenching it in water, this makes it less, malleable and resistent to bending in future. Always allow a safe 'fall area' just in case.
Rawbolts are used usually "eye" ended to attach the guy lines, these are finally tensioned to remove excess play hold the mast vertical, and to give proper support.
GENERAL WIND POWER INFO.
There is some growing support for utilisation of limited wind power production in urban areas, (see http://www.urbanwindenergy.org.uk/), no one could ever say conditions are even close to ideal as in parts of Scotland, the Western Isles like Stornoway or the Northern Irish coast, but some might argue that even a small contribution from home production will have some benefit in reducing emissions, and the Government agrees, with plans to ease planning restrictions to encourage it.
Wind energy in the 9-25 mph windspeed is the most common here in U.K., so a turbine producing fair energy output at these lower velocities is preferable to one that only makes good energy only in the 25-45 energy rich area (which obviously occurs less often). Rotor/ blade diameters will be increasing steadily to improve lower speed performance logically and also according to the A.W.E.A, which will make small wind turbines even more practicable than at present.
Have a look at the B.W.E.A. website, which is informative.
Perhaps people will think more carefully about energy issues and waste, if exposed such technology as wind turbines or solar power close to home, greenphase (UK) is a good web site if looking for alternative energy supplies.
One of my recent customers Bob and his wife Pauline who live in Southern Spain invested in a 1kwatt turbine (the white finned alloy bodied one on technology page) as he (in common with many others in rural Spain) manages without grid power but has bountiful wind energy. Having some reliable wind power with a small petrol generator as a backup, means power for lighting refrigeration T.V. without paying for a VERY expensive grid connection, wind turbines are becoming quite a common site in country areas apparently.
SPAIN HAS A MASSIVE TURBINE BUILDING PROGRAMME NOW, AS THEY ARE PHASING OUT NUCLEAR POWER COMPLETELY!
As used in Blackpool, see Company video of this one in action http://quietrevolution.co.uk/
In America most wind power enthusiasts / user information recommends mounting any turbine on a 30 or even 40 foot pylon or tower, this is very high, but where possible is ideal. The potential wind energy up there is MUCH greater than close to ground, and even though the tower/ mounting may be as expensive than the actual turbine, the payback in terms of overall energy production would prove worthwhile over a relatively short time.
In Ohio and many other States there are many communities who manage without grid power and through inginuity and economy manage on wind / diesel generation alone, the same still applies for a some places in rural Wales Eire and Scotland.
Within the body of a pmg or pma, are a collection of extreemly powerful rare earth magnets ,usually these are arranged to spin with the blades assembly unit, the copper coils (in which the electricity is made) in this case are stationary, power is then fed out of the turbine usually from 3 wires (3 phase) where it can be rectified if wished from A.C. to D.C. Direct Current (similar to a car battery).
video clip of diy turbine, www.youtube.com/wind4watts
500 Watt pmg unit 3 Phase rectifier to supply DC and a Hand held Anenometer
Turnbuckles for support guy wires 700 Watt 12v-240volt inverter
D.I.Y. TURBINES
D.i.y. wind turbines are pheasible with a bit of planning, sourcing suitable parts and some basic engineering skill/ knowledge some experimentation will often be needed. Choose a proper/good pmg. (futurenergy supply these for one, and blade sets) You can make blades from fashioned wood with routers planes etc. A self built pmg is possible but it does take some skill and patience, making hand wound copper coils and using rare earth magnets which are available now. Plenty of information on Hugh Piggots and U.S. websites.
These designs work very well with good outputs (50-70 Amp has been seen in strong winds) and often use brake disks as a basis for the pmg rotors, but they can fall to bits when the epoxy holding the magnets freezes and loosens letting the magnets free. This renders these units inoperable, this is disheartening after so much work. What is needed are units that are capable of many years of reliability with just some occasional maintenance.
Choose or make a good blade set, it can be problematic making an effective shaped efficiently angled blade, similar to an airscew angle wise, we are after decent start up torque, so go for a good surface area wider chord types seem to work best, steeper 20+ degree at the root if possible, and a gradually feathered shallow angle 5-8 degree towards the tips with thinnish aerodynamic 'wing' section, to allow a capability of reaching and withstanding 300+ to possibly 900+ rpm a good typical operation range could be 300-500rpm, though when a pmg is working, it drops the revs down a lot, due to inductive resistance as it does it's work driving the magnets around past the coils making power.
If you slip a charge supply wire off briefly (not normally recommended) , so the pmg isn't under load, the revs rise rapidly from a modest but charging 13.5-14volt 230rpm to 600+ rpm and 60 volts in a 15 mph gusty wind.
Serious mis alignment in the rotor/blade mounting shaft/plate e.t.c. or badly balanced blades can often mean it could literally shake itself to pieces eventually, ruining a potentialy successful and productive device if the problem isn't rectified.
Care in construction, like weighing/matching the wind turbines blades , final rotor balancing and "real life" testing is the best way. Use a thin rope on the tail to turn the test turbine out of strong wind if need be. 1.8 metre diameter, 5 black plastic bladed sets are available 'off the shelf' now from futerenergy in U.K. and are quite flexible tough and smooth running, if used on a suitable (1kw or smaller) size pmg , generally a very good product for diy use which i have used.
GRP 3 blade sets are also on e bay U.S. by Powermax, and look similar to the ones in Chinese kits i have stocked, (photo page with the long finned alloy casing pmg), i haven't tried these but go for an adequate diameter for your pmg, larger if unsure, they are reasonably priced at least, but check shipping costs.
Some type of self furling to limit maximum strains in Gales is really a 'must' especially in high wind areas. Most usually this involves a tail boom unit which swings to one side turning the blades out of the wind, lowering the revs and strains, or the unit itself can be set to turn turn to an angle to the oncoming wind though usually, and ideally still producing quite reasonable power. Almost all wind turbines require some type of protection. 5-8 bladed turbines tend to 'self limit' to some degree as revolutions go very high, due to aerodynamic effects as one blade enters disturbed air from the previous one.
Pictures of an experimental turbine made good power, and was a good testbed.
The exact methods to make furling work is too engrossed to go into here, and varies with each set up, some experimentation is often required to get it right. Most PMG's can also have a 'braking' mode feature, to slow blade rotation. Please see Hugh Piggots informative website (scoriag wind) he's a pioneer in the wind power world. Most of Scoriag Pininsula and others have used wind power for years through neccesity apparently. He also sells books with comprehensive plans on how to build pmg's and turbines.