Throughout the 2010 World Expo in Shanghai, green has been the chief buzz word. From solar panels to rooftop gardens and eco air conditioning, more than 200 pavilions from around the world are showcasing new green technologies.

The new technologies being shown at this year's Shanghai World Expo are almost all tinged with green.

The 5.28 square km site is brimming with all things eco friendly.

The China Pavilion and Theme Pavilion themselves are fitted with solar panels on their roofs.

The Expo axis has been designed as a parade of so-called "sun valleys" - sunlight catchers that light the multi-level walkway and collect rainwater for use in cooling the structure.

Each pavilion has taken on the challenge in a different way.

The Shanghai Pavilion, called EcoHome, showcases a home of the future, with rooms for grandparents as well as children and examples of how to save water.

Fan Yifei, Ecohome's Architect, said, "Eco-architecture doesn't have to be unattainable or very expensive. Instead, it can adopt elements that already exist in traditional culture."

The model home features solar panels and a rooftop garden that cools the building in the summer and offers a sun terrace in the winter.

The Finland Pavilion packages sustainability in modern Finnish design. The entire building, known as the Giant's Kettle, is covered in shingles that resemble fish scales.

The building has been designed to have a long life cycle, past the end of the six-month long World Expo.

Mikko Puustinen, Deputy Commissioner General, Finland, said, "I think Finns are serious about sustainability so we don't like it to be just thrown away after the Expo so we want to find a good home, and also hopefully in a small way but still in an important way to

contribute to the sustainable principle and also practices in China."

The Swiss Pavilion is strikingly different. The pavilion is meant to address the idea of urban-rural interaction.

The director says that the design showcases the fun side of sustainability.

Manuel Salchli, Swiss Pavilion Director, said, "The solar cells absorb the solar energy that is around, there's plenty in Shanghai, and then there are LED lights which are powered with these solar cells and they blink and they actually show to the

visitors how much energy there is available which could be used sustainably."

The nearby Denmark Pavilion features walls pockmarked with holes on all sides. The building uses little air-conditioning, depending instead on fans to cool down the pavilion.

The pavilion showcases Denmark's own vision for what a modern city could look like.

The walkway in the pavilion also features a lane specifically for bikers.

Denmark, known as the Kingdom of Bicycles, wanted to represent that aspect of their culture to visitors through the Pavilion.