This « eternal stretching street that is elegant as an I » as Victor Hugo, used to say was created in the 18th Century to resolve the traffic jams and the hygiene problems in the overcrowded old districts by controlling at the same time the popular uprising of the capital city. The model of the rue de Rivoli was extended to all the new Parisian streets leading to a standardization considered by some artists of that time such as the architect as «stifling monotony».
 
The « Mountain Towers » project aims at controlling smog, making denser and naturalizing thus type of hyper energy and space consuming urbanism by the construction of bioclimatic mountains integrating the renewable energies on the roofs and in the heart of the blocks. The « Mountain Towers » with positive energies will enable thus to triple vertically the housing in each Parisian housing block by distributing the structural loads through the old ducts of blocked chimneys.
 
Three types of renewable energies will be available in each tower : During the day, two huge photovoltaic and thermal solar shields bio inspired by the structure finely cut from dragonfly wings will produce electricity and hot sanitary water. At night, a reversible hydro-electrical pumped storage station will let an urban cascade flow out from the top of the tower between to basins of rainwater retention tanks located at different levels, preventing the need of batteries to store the electricity produced by the solar dragonfly wings.
Finally, the garden balconies will surround the inhabited storeys and filter in clean recycled waters rejected by the inhabitants by phyto-purification and bio-composting.

These depolluting towers will offer a strong urban density of cultivated housings thanks to their minimal impact in the ground and their architecture in splay. They will be integrated at the geographical crossings between the radial Parisian boulevards and the PC and along the existing ecosystems such as the Buttes Chaumont, the Monsouris Park, the André Citroên Park, etc.
 
Energetically, these towers will produce electricity by the integration of axial wind turbines of Darrieus type in the strengthened facade on the one hand and on the other hanf in photovoltaic flexible textile that enable the rainwater and dew on the roof. Regarding the thermal part, the temperature differential with the tunnels of the Petite Ceinture will be used to create geothermal cooling/heating tubes enabling to bio-air condition passively the surrounding air inside the tower. These tunnels will be lighted by piezoelectrical promenades.

In 2050, Montparnasse tower will thus be a carbon neutral BEPOS ecosystem without fossil fuels built under the shape of a vertical public park on several floors overhung by sky gardens. Banisters will meander around the reinforced structure and will offer helical piezoelectrical promenades in the sky of Paris around the 58 floors in the shape of almond.
 
In the triangular openings located at both extremities of the tower, the public elevators with renewable energy will be integrated in order to separate the visitor ways from the staff working in the offices of the tower. The slab-roof of the shopping mall will be transform into a phyto-purification lagoon recycling the used waters of the building.
This planted green space in the heart of Paris will cover Montparnasse tower as well as other smaller towers (building C ad Express tower) with an insulating bio-facade that produces biofuel. Green micro algae will be cultivated on curtain-walls in planar and triangular photobioreactors built in laminated glass. They will capture the thermal solar energy by serving in the same time the generation of biomass used to produce methane. The CO2 will be used as nutrients to the algae that proliferate under the solar radiation. These bioreactors will enable to improve the thermal inertia up to 50% of heating and air condition saving whereas the biofuel refinery will be directly integrated in the base of the building. 

Besides the bio-air condition of the atmosphere provided mainly by the evapo-perspiration of the plants, and in addition to the electricity generated by the axial wind turbines implanted on the roofs-blade in the funnels, the main energy source will come from the concentrating thermodynamic plant. This will be composed of a collector implanted on the “Abeille Tower” and parabolic helio-static mirrors planted on the Parisian zinc roofs and concentrating towards the collector the sunrays to increase the temperature of a heat transfer fluid. This liquid will be sent in a water heater transforming the water into steam. The steam will make the turbines turn which will pull the alternators producing thus electricity even outside the solar irradiation time, i.e. 24/7.
The towers of Villa d’Este will be BEPOS (Building with positive energy) whereas the inhabitants will cultivate their own organic food in this nourishing ecosystem, new social innovation ground !

In order to increase the offer of housings in Paris, the « Honeycomb Towers » propose to double the height of theses HBM by an architecture leading to the construction of individual mini-houses interlocked the ones to the others. Such as a honeycomb with hexagonal alcoves, this urban implant will offer to the new inhabitants vegetable gardens and suspended orchards repatriating thus in the city the advantages of a rural individual house. Structurally, this hive is supported by a steel structure that descends the loads vertically through the existing chimney ducts crossing the buildings.
 
Actually, from the 1^st January 2015 the wood combustion will be totally forbidden in Paris and these ducts already drilled will find a second use. The structure in honeycomb will enable to reinforce the resistance of the tower by assuring maximum lighting. The single-family module will be standardized and prefabricated. The concepts of double-wall and double deck will be directly integrated for a maximal spatial flexibility, an efficient innervation of the fluids and an optimal thermal and sound insulation. This great meccano toy with an organic silhouette will be transformed into a true suspended nourishing garden in the sky inviting the Parisian fauna and the flora to thrive
The roofs will be covered by thermal and photovoltaic solar panels whereas the Sérurier and Mortier boulevards, the Phylolights (hybridization of a lamp and an axial wind turbine) will assure the public lighting self-sufficiently. 

 
The objective is to repatriate the countryside in the heart of the city and to reintegrate the food production locally. True city district piling up mixed blocks, these Farmscrapers make denser the urban space by optimizing the quality of life of the inhabitants by the reduction of the transport means, the implantation of a domotic network, the renaturalization of the public and private spaces and the integration of clean renewable energies as the biomass, the methanisation, the photovoltaic and thermal solar energy and the wind turbines.
This pioneer project aims for the 8 following objectives :
1/ The reduction of the ecological footprint enhancing the local consumption by its food autonomy and by the reduction of the transport means.
2/ The reintegration of the local employment in the primary and secondary sectors coproducing fresh and organic products.
3/ The recycling in short and closed loop of the organic waste by anaerobic compost, hydrogen fuel cells and phyto-purification lagoon.
4/ The saving of the rural territory, reducing the deforestation, the desertification and the pollution of the phreatic tables.
5/ The oxygenation of the polluted city centres whose air quality is heavily polluted.
6/ The limitation of the systematic recourse to pesticides, insecticides, herbicides and chemical fertilizers.
7/ The water saving water by the recycling of the urban waters.
8/ The protection of the ecosystemic cycles in the heart of the city. It’s a project of BEPOS living stones reintegrating the biodiversity ! 

As their name indicates it, the « Mangrove Towers » will be inspired by the mangrove trees of the maritime marshes with their pneumatophores and their stilt roots. They will be implanted directly of the platforms of the Gare du Nord and they will ramify each other as ecosystem resilient to the climate imbalance. These towers will accommodate a mixed programme of offices, hotels and housing dedicated to international and traveling customers. True forest of planted towers, this urban mangrove will be energy positive, that means i twill produce more energy than it will consume (electrical, calorific or food energy).
The project will be eco-designed from state-of-the-art renewable energies to present a zero carbon footprint. Indeed, the station platforms will be full of piezoelectrical captors polarizing under the action of the mechanical constraint generated by the travelers. The tubular facades will be composed of Grätzel cells forming a photo-electrochemical skin inspired by the light (photons), will also produce the electricity by electrolysis. Finally, the towers will not only be self-sufficient in energy but they will be also depolluting thanks to their structure in titanium dioxide.
Their structure in branches (imitating the bark of mangrove trees) will cause under the action of the x-rays in the presence of oxygen and humidity, the degradation of the organic, solid, liquid and gaseous matters in the urban smog (through self-cleaning, destruction of COV, destruction of NOX, anti-mist, UV absorber, etc.).
 

They will be twin towers molding and re-customizing extraordinarily both existing bridges of the ring road in order to enhance both entrances to the city by the river along which its history flew from Lutece. Perforated by wide funnels, the towers will be supplied by electrical energy thanks to multi blades wind turbines replaced by hydrokinetic turbines (hydroelectrical turbines) which will use the kinetic energy (river motivity). The conveyors of these water wheels will enable to reestablish the rotary movement of the axis from the linear movement of the river. The heat pump will enable to capture the water calories of the Seine to heat the towers. By this use of renewable energies, the towers will be BEPOS building, i.e. with positive energy.
True urban link, this bridge, until here passage between two banks, will be a new territory created by a new urban form linking two towers of more than 200 meters. By its junction, it will reinforce the urban continuum by affirming in the same time its particularity, which is to be linked to the river that it crosses and to the grounds it reconnects.

This inhabited bridge, these two amphibian towers across the Seine, will meet the housing crisis of the city of Paris by including a dense and mixed programme facilities , but also hotel-apartments to meet the needs of the « world city ». The inhabited bridge will reinforce the symbolism of the city and will refer to a new form of urban and social innovation in terms of clean collective housing with zero carbon emission and zero waste!
 
Copyright : Vincent Callebaut, Lead Archibiotect

More information:
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Passage du Cheval Blanc, Cour de Mars
F-75011 Paris
+33 (0)1-43430856
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