Dynamo Hubs For Wind Turbines

Dynamo Hubs and bottle dynamos for use in small DIY wind turbine generators

A common way of learning more about wind turbines is to build your own with easily available cheap parts. For many years now old Sturmey Archer Dynohubs (1) have been used for this purpose. Available at scrap prices, they generated 3 Watts at 6 Volts - perfect for lighting some LEDs or small bulbs. However as more and more people have caught the wind power (2) bug, these 40 year old hubs have become more and more pricey and difficult to find, and are finally approaching the prices of new modern equivalents.

Retail prices for dynamo hubs typically start at around £30-40 for the most basic model, up well into the hundreds of pounds. However, for use in a small wind turbine generator the cheaper models are perfectly acceptable. The difference in price gets you a lighter weight hub (a disadvantage) and a little less resistance, better weather-proofing, and improved build quality (all advantages).

Bottle Dynamo Wind Turbines

Pictured above is a simple wind turbine generator made using a bottle dynamo. While these are available cheaply, unfortunately, they do not make very good generators as the voltage output at typical turbine rotation speeds is too low for battery charging. A voltage multiplier (3) is therefore recommended with a bottle dynamo in order to get a more useful voltage.

Alternatives to the Sturmey Archer Dynohub

Here are the details of some alternatives to the Sturmey Archer Dynohub:

Shimano Nexus Dynamo Hub

6 Volts and 3 Watts of power, this dynamo hub is designed for use as a front wheel hub and comes complete with a switch. Typical retail prices are Ł40-75 however previous year's models can sometimes be found for as little as £20.

Schmidt Dynamo Hub

This Scmidt Dynamo Hub is also a 6 Volt 3 Watt model, however it is the most efficient hub dynamo available (99.77% efficiency claimed). Priced at over £100 retail it is getting very close to the typical price of a Permanent Magnet Alternator (4) made specifically for wind turbine use and with a far higher power output (hundreds of Watts). Therefore you would be very unlikely to invest in this ultra-reliable superbly well-sealed little generator - but if you happen upon one in a few years at a car boot sale or on ebay, snap it up right away!

Buy a Dynamo Hub

One of the best places to purchase a well priced used or new dynamo hub is eBay UK (5). Click here to search now for Dynamo Hub (6).

Web Link References

(1) http://www.reuk.co.uk/Sturmey-Archer-Dynohub.htm
(2) http://www.reuk.co.uk/wind.htm
(3) http://www.reuk.co.uk/Making-Voltage-Doublers-and-Multipliers.htm
(4) http://www.reuk.co.uk/Permanent-Magnet-Generator.htm
(5) http://rover.ebay.com/rover/1/710-53481-19255-0/1?type=1&campid=5335956244&toolid=10001&customid=
(6) http://rover.ebay.com/rover/1/710-53481-19255-0/1?type=3&campid=5335956244&toolid=10001&customid=&ext=dynamo+hub&satitle=dynamo+hub

Article from REUK.co.uk:
http://www.reuk.co.uk/Dynamo-Hubs-For-Wind-Turbines.htm
Published: 11th April 2009
Š REUK 2009