Taos, United States - It's a green architectural movement that took root in the desert of New Mexico some 40 years ago. That's when Michael Reynolds, 69, began experimenting with building homes out of garbage and natural materials that he called "Earthships".

"I was [called] an idiot for building out of garbage, but people are starting to realise that maybe there is something to look at here," Reynolds told Al Jazeera. Although it hasn't been an easy journey, Earthships are becoming a more mainstream housing option. Today, people are living in Earthships in 50 states across the US, and in at least 25 countries around the world.

Earthships are built by digging at least 1.2m below the earth's surface, where the temperature remains stable throughout the year, thereby needing no fossil fuel-derived energy for cooling or heating. Exterior walls are made of recycled materials such as truck tyres, used bottles and spent beer cans.

Solar panels and wind turbines on the house generate enough electricity to run electrical appliances.

Earthships also harvest their own water from rain or snow, and store it in a huge tank on the roof. This water goes through a filtration system and is used for drinking and cooking.

More on the story