The global economic slowdown isn’t stopping some architectural designers from coming up with new and greener ideas for city living. Just take a look at the following innovative eco-skyscrapers:

California-based design firm Nectar proposes a skyscraper designed not for people but for trees. The CO2 Scraper (pictured at left) could hold 200 to 400 large trees high in the air to absorb greenhouse gases, and would use wind power for most of its energy needs.

Completed last August, The Sail @ Marina Bay (at right) is the tallest residential high-rise building in Singapore, according to NBBC, the architecture firm that designed the structure. The building, expected to be recognised with Singapore’s Gold Standard of Sustainability, offers a mix of residences, restaurants and recreational facilities under two tall roofs.

Perkins Eastman has proposed two designs for the Kohinoor CTL competition in Mumbai, India. Both structures (one at left) include such features as rainwater harvesting and recycling, alternative energy sources, solar chimneys and facade plantings for air filtering.

Located in Nagoya, Japan, design firm Nikken Sekkai’s Mode-Gakuen Spiral Towers (at right) are designed to be more than earthquake-proof. They’re also built with double-glassed windows in which air flows between the two panes to reduce heating and cooling costs.

Finally, architect Daniel Libeskind has come up with a design for a 54-story residential tower (at left) in New York City. The structure would feature terraced gardens placed within cutout areas along the length of its facade.

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