greening Paris - and Mumbai, Beijing, Chicago...

From Inhabitat, two innovative building projects in Paris.

Anti Smog is a project that takes "air rights" to new levels of sustainability:

[Architect] Callebaut describes the process as an intention to “absorb and recycle by photo-catalytic effect the cloud of harmful gases (Smog) from the intense traffic near Paris.” Under the smog eating exterior, the building houses public spaces with a central courtyard and natural lagoon, a place Callebaut envisions for teaching opportunities about urban ecology and renewable energy. The Solar Drop also harvests rainwater from green space on the roof for use inside the building.

Energy Plus is an office building intended to be zero-energy, generating all its energy requirements:

How does this building achieve its goal? For starters, the building will be heavily insulated - enough to reduce its energy use to about 16 kilowatts per square meter, which is considerably lower than that of a standard building. Cold water from the Seine river will be pumped throughout the offices eliminating the need for a standard air conditioner unit. And to actively contribute to the highest standard of energy efficiency, designers have engineered the building to have the largest solar array in the world installed in the roof. It is this solar array which will provide all the energy needs of the building, as well as providing additional energy to be fed back into the grid.

And the Wall Street Journal showcases the energy-saving strategies of nine cities from around the world. As usual, Africa doesn't feature.