Lotus effect

how the lotus get rid of the water

Thanks to a nano structure, the droplets of water cannot wet on the leaves of the lotus. As a consequence, the droplets of water just rolls onto the leaves recovering the dirt.
The scientists have mimic this structure in order to keep walls and windows clean.
In the case of our building design, this lotus structure must recover at least the glass roofs. So the building will not need any cleaning: it will save energy.