What do you think of this wind generator?

Colvic Watson

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I was browsing in Maplin online (honestly, could anything be more fun?) and came across this. Maximum output is 4amp so even if it averaged 1amp you could buy 3 for for the cost of a Rutland and another one for the cost of a Rutland pole, and a 5th one for the cost of installing a Rutland - that's 5Ah for the cost of a 913 - great kit but average 1.5Ah.

Built in charge controller and one review says average 1Ah.

http://www.maplin.co.uk/50w-telescopic-vertical-axis-wind-turbine-396269
 
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I was in Maplin today and picked up a leaflet which included this.

It's certainly an interesting price but the download PDF which gives more info does mention a "start up" windspeed of 8-10m/s. That's force 5, and the implication is that it won't be doing anything at lower windspeeds.
Some of the feedback comments are not very flattering.
I was tempted, but I won't be getting one.

Despite that, Maplin have some interesting offers at the moment. A 15W solar panel at £49.99, a gas soldering iron at £14.99, and one of the telescopic ladders which were being discussed recently, at £69.99.
They are running a "Caravan & Out essentials" promotion at the moment so there may be a few other bits and pieces that forumites would be interested in
 

elton

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Gadzooks! I've been thinking of building something similar! I did loads of research into the theory and the blade design of these so called Savonius type turbines. No need now. I'll be 'aving one of those pronto.
 

Ceirwan

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If they say that, they don't know what they're talking about. 1Ah? In how long? Ten minutes? A week?

This is, at best, a keep-the-batteries-topped-on-a-mooring up device. Get a solar panel instead -- they're telescoped down to almost nothing as standard :)

By using a little bit of intuition I would say they mean 1amp every hour ;)
 

elton

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I think these Savonius turbines have a future and a place, but this Maplin one isn't it. What they need is some way of producing a charging voltage (at reduced current) at low speed. The way they work at present seems to be to generate zero charging current until they reach a high enough speed, and to simply dissipate energy when they're producing too high a charging voltage. Some kind of intelligent electronics is required, and I haven't worked out how to do it. Neither have they.
 

Bru

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I think it's badly engineered

A startup speed of WHAT? 8-10m/s on a Savonius VAWT?

That says to me that the designer(s) opted for an excessively large dynamo in order to be able to claim an output of several amps at the cost of getting any output at all from the thing at more commonly experienced lower wind speeds

Locked away on my annoyingly faulty hard drive from previous confuser (which being a "retired" IT person I had, of course, failed to back up :() is my design for a Savonius VAWT to power a 15W pond pump and from memory I think I worked out that to power that permanently I needed something getting on for three time the size of the unit Maplin are offering

A properly designed Savonius blade is self starting at very low wind speeds if there is no load to be driven - after all, that's basically what your cup anemometer is. The more torque required to start the dynamo or alternator spinning, the higher the wind speed before the blades can start to rotate (obvious really).

A design that seeks to generate 4A at 12v from a roughly 2' high by 1' dia VAWT does not strike me as being very clever since it requires a wind speed well above the average to even start generating. If the dynamo was much smaller it would start up on a much lower wind speed and probably then generate useful amounts of power, enough to trickle charge a battery, at or below average wind speeds (which in the UK are generally around 5m/s give or take).

Then, at the price being charged, it might be a useful piece of kit in parallel with a reasonable solar panel for trickle charging. Of course, a max output of 1A or 2A wouldn't look half as good on paper.

In my 'umble, it's a toy

(it's worth noting that a Rutland 504 needs a wind speed of over 30 knots to reach an output of 4A - at which point the Maplin VAWT would just about be starting up)
 

robertj

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Don't bother with Rutland either, very poor charging in my opinion. Yourebetter off buying solar, more power and quiet.
 

oceanpilgrim

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dont wish to be rude but there must be some thing rong with your rutland then or the way its wired in,
i have a rutland 913 and it supplies all the power needs of my 40 footer,i also have two 80w solar pannels and there not worth a dam in uk waters,
 

Colvic Watson

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OK - Quite a bit wrong with it then! I agree about the design of the dynamo, if it had a max output of 2ah but started at about 10knots wind speed that would be more useful. BTW the Rutland 504 may be a bit pitiful but I agree that the 913 is a very effective charger.
 

Sy-Revolution

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OK - Quite a bit wrong with it then! I agree about the design of the dynamo, if it had a max output of 2ah but started at about 10knots wind speed that would be more useful. BTW the Rutland 504 may be a bit pitiful but I agree that the 913 is a very effective charger.

Good for weekend use, always got back to the boat on Friday with a good 14.2v in the batteries (swing mooring). But of very much less use now that we liveaboard. I reckon I lose more power from the shadow it creates on the solar panels than it puts in. Maybe in windy Greece it will perform a little better......
 

CharlesSwallow

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I doubt the mechanical suitability for use on a yacht..

..Get that on a yacht moored somewhere exposed to a lot of swell, Poole, off Baiter for example, and I wonder how much whiplash such a device would endure. Then there is the to-ing and fro-ing of normal passage making.

The Forgen is much shorter so is able to withstand such forces. This thing is intended for fixed mounting on buildings by the look of it. I wouldn't want to be on deck when the bearing or bracket failed and it came crashing down.

It is surely well known that this design of wind generator is hopelessly inefficient in light winds anyway.

Chas
 

jwilson

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I was browsing in Maplin online (honestly, could anything be more fun?) and came across this. Maximum output is 4amp so even if it averaged 1amp you could buy 3 for for the cost of a Rutland and another one for the cost of a Rutland pole, and a 5th one for the cost of installing a Rutland - that's 5Ah for the cost of a 913 - great kit but average 1.5Ah.

Built in charge controller and one review says average 1Ah.

http://www.maplin.co.uk/50w-telescopic-vertical-axis-wind-turbine-396269

held in place by a strong magnet, the website says... Ideal for near your compass.
 
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