The Tourneseul is an automated, autonomous device for reflecting the sun's rays featuring a mirror which functions like a sunflower.

Its ability to find and follow the sun’s position enables it to redirect a quantity of light onto a given target.


An autonomous heliostat.

Heliostat : noun. 18th century.

Composed of helio, which is Greek for sun, and the suffix « stat », from the Greek « statos », meaning « stable, steady, stationary ». An instrument fitted with a mobile plane mirror which moves automatically so that it reflects the sun’s rays in a fixed direction, regardless of the Earth’s rotation.

an instrument consisting of a mirror moved by clockwork, for reflecting the sun's rays in a fixed direction.


The Idea.

Whenever the sun appears, the Tourneseul locates its position and reflects its rays toward a predetermined target. Its axis orientates the reflective surface so its perpendicular bisects the angle between the sun and the target.


It’s easy !
As soon as a sufficiently strong ray of sunlight appears, the cells move the reflective plate into place in less than a minute. The plate then reflects the rays towards a predetermined spot. From then on the system automatically follows the sun’s movement, ensuring the light is constantly reflected onto the chosen target.


The Tourneseul : a source of soft water.

The concentration of light energy can also be used to extract the salt from salt water, with or without the conversion of heat into electricity.


Not enough light in a room ?

Thanks to the Tourneseul it is now possible to send sunlight into a room that gives onto a dark courtyard and into other spaces that don’t usually benefit from natural light, such as rooms with just a north-facing window and homes situated in a steep-sided valley.

For example, your bathroom is situated at the back of the house and you would like some sunlight while you’re getting ready in the morning. Now you know about the Tourneseul, sunshine will soon be beaming into your bathroom.


A project in development involving a group of Tourneseuls.

Combining the output of several Tourneseuls – in effect, a sort of solar power plant - could be used to produce large amounts of energy.


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