When the world gets closer.

We help you see farther.

Sign up to our expressly international daily newsletter.

Already a subscriber? Log in .

You've reached your limit of one free article.

Get unlimited access to Worldcrunch

You can cancel anytime .


Exclusive International news coverage

Ad-free experience NEW

Weekly digital Magazine NEW

9 daily & weekly Newsletters

Access to Worldcrunch archives

Free trial

30-days free access, then $2.90
per month.

Annual Access BEST VALUE

$19.90 per year, save $14.90 compared to monthly billing.save $14.90.

Subscribe to Worldcrunch

Capturing Energy From A Flag Flapping In The Wind

French scientists have discovered how flags, made of the right material, can be an alternative to wind turbines.

Blowing in the wind
Blowing in the wind
David Larousserie

PARIS — Are traditional bulky turbines the only way to capture the energy blowing in the wind? The answer, my friend, is apparently No.

Earlier this year, a team of scientists from Ecole Polytechnique and Paris Superior National School of Advanced Techniques (Ensta ParisTech) measured how a "simple" flag made of the right material can also be well-suited for the production of energy.

Over the last decade, researchers have been working on the possibility of producing power out of such undulations of a flexible membrane in water, another fluid, or in the air. Piezoelectric ceramics, which create tension when being deformed, are among the most promising materials.

According to the simulations published in Physical Review Applied, the more wind there is the more electricity it creates, though not proportionally because of the erratic undulations of the flag. Where it is interesting, however, is that for the first time, it highlights that the wind is not the only factor in the efficiency of the system; the type of circuit to which it is tied also has great influence. Sébastien Michelin, from l'Ecole Polytechnique, and Olivier Doaré, from Ensta ParisTech explain that "within certain conditions, the productivity can jump from 0.1 to 6%."

Thus engineers are now working on the fabric of flags but also on the composition of circuits. The mechanical and the electrical system are joined together. Thanks to that, even if completely down, a flag would still be able to produce a few electrons. "By influencing the flag dynamics with the electronic components so as to adapt to the wind conditions, we can make it work in many more cases," notes Michelin.


How many flags?

The team is optimistic, noting that making improvements to the electric circuits is not necessarily a complicated task. Christophe Eloy, researcher at Ecole Centrale in Marseille, points out that "they are not the first ones to have the idea to use flags but they are the first to have properly detailed the system."

In reality, these technologies, producing less than 1 watt, will not replace the wind turbines that produce a million times more than the flags. They will, however, be useful for recharging batteries, for example.

Many questions still need to answered; how many flags and in which position? If all of them were in synch, conditions would optimal. Unfortunately, Christophe Eloy and his collaborators showed in 2009 that if three flags were put right next to each other, only two flags would be waving and the one in the middle would stay motionless.

You've reached your limit of free articles.

To read the full story, start your free trial today.

Get unlimited access. Cancel anytime.

Exclusive coverage from the world's top sources, in English for the first time.

Insights from the widest range of perspectives, languages and countries.

eyes on the U.S.

Murdoch's Resignation Adds To Biden Good Luck With The Media — A Repeat Of FDR?

Robert Murdoch's resignation from Fox News Corp. so soon before the next U.S. presidential elections begs the question of how directly media coverage has impacted Joe Biden as a figure, and what this new shift in power will mean for the current President.

Close up photograph of a opy of The Independent features Rupert Murdoch striking a pensive countenance as his 'News of the World' tabloid newspaper announced its last edition will run

July 7, 2011 - London, England: A copy of The Independent features Rupert Murdoch striking a pensive countenance as his 'News of the World' tabloid newspaper announced its last edition will run July 11, 2011 amid a torrid scandal involving phone hacking.

Mark Makela/ZUMA
Michael J. Socolow

Joe Biden was inaugurated as the 46th president of the United States of America on Jan. 20, 2021.

Imagine if someone could go back in time and inform him and his communications team that a few pivotal changes in the media would occur during his first three years in office.

There’s the latest news that Rubert Murdoch, 92, stepped down as the chairperson of Fox Corp. and News Corp. on Sept. 21, 2023. Since the 1980s, Murdoch, who will be replaced by his son Lachlan, has been the most powerful right-wing media executivein the U.S.

While it’s not clear whether Fox will be any tamer under Lachlan, Murdoch’s departure is likely good news for Biden, who reportedly despises the media baron.

Keep reading...Show less

The latest