State of the Art of Windthermal Turbines

As Low-tech Magazine wrote in 2019, given the right conditions, a mechanical windmill with an oversized brake system is a cheap, effective, and sustainable heating system. Earlier this year, Malte Neumeier from the German Aerospace Center informed us that he and his team are investigating the technical and economical challenges of the technology.

“We started our research, with a birds eye techno-economic analysis and a scoping review. The results were promising, so we decided to build our own prototype. To refine our analysis, we are now searching for people, who already have experience with this technology. Maybe we could discuss some lessons learned. Do you have contact to any person experienced in wind-thermal energy applications? I would really appreciate this.” [Read more…]

Klopotec: a Bird-Scaring Wind-Rattle

A “klopotec” or “klapotets” is a wooden mechanical device on a high wooden pole, similar to a windmill. It is used as a bird scarer in the vineyards of traditional wine-growing landscapes of Slovenia, Austria, and Croatia. The first written mentions of the technology date to the second half of the 18th century, whereas its oldest depictions date to the first half of the 19th century. [Read more…]

Windmill on Ice or Water Bearings Has Low Friction at Low Cost


Simon Gripenberg, an artist from Finland, developed new types of vertical windmills, inspired by ancient Persian windmills and built from recycled materials. Most interestingly, the windmills float in water or spin on ice, so that Gripenberg manages to obtain low friction at low cost. [Read more…]

Wind Power System Made from Plastic Buckets

A wind power system made from plastic buckets is seen on boats at a floating village in Hanoi, Vietnam June 29, 2016. REUTERS/Kham

A wind power system made from plastic buckets is seen on boats at a floating village in Hanoi, Vietnam June 29, 2016. REUTERS/Kham

“Vietnamese families living in slums along the Red River in Hanoi are using red plastic buckets and old printers to help light homes, cook meals and slash electricity costs by as much as a third.

The recycled goods form the blades and motors of electrical generators that power old motorcycle batteries to illuminate lamps with a brightness equivalent to a 45-Watt light bulb.

Though the output generated is small, it makes a significant difference for families previously denied power because they lived too far from a power station or had to ration supply because of the expense.”

More pictures and information at Reuters: Plastic buckets, broken printers shine light on Hanoi’s poor. Via Playground Magazine.

See all our low-tech windmill posts.

Different Types of Windmill Sails

different types of windmill sails compressed 700 pixels

François Porcher has translated our 2009 article “Wind Powered Factories: History (and Future) of Industrial Windmills” (“Des fabriques mues par le vent: histoire (et avenir) des moulins à vent“) and sends us the image above to complement the illustrations. For a high-resolution image, go here. More articles have been translated to French and other languages.

Previously:

Self-Trimming Wingsails

Self-trimming wingsail“Since the invention of aircraft, a similarity has been noticed between the operation of sails on boats and the function of wings of aircraft. Sails on boats provide thrust in a horizontal direction derived from moving air, and wings on aircraft provide ‘lift’ in a vertical direction to support a plane in the air, also from moving air (relative to the plane). In order to fly, wings had to have a certain degree of efficiency, and some experimenters have realised now that aircraft-type wings could be used on a boat and would be more efficient than sails.”

“Having tested wings on boats in place of sails (‘wingsails’) designers noticed another feature used on aircraft that would be useful to use in conjunction with wingsails – controlling the wingsail with another smaller surface mounted behind or in front of it (a ‘tail’). There are many examples of tails used to control the direction of bodies both in the water and in the air, and aircraft use them to adjust, to a precise degree, the lift or (angle of attack) of their wings.”

“If a tail is used attached to a boats’ wingsail, it can adjust the wing perfectly to every small change of wing direction, in this way relieving the sailor of this task, which is mostly guesswork and at best very approximate, and it can perform that job much better than any sailor can do. Such a wingsail/tail combination is referred to as a self-trimming wingsail.”

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