Living PlanIT is planning to build the world's greenest city from scratch at a site in northern Portugal. Establishing its PlanIT Valley development as a working template for a new generation of low carbon cities, ones that combine real environmental sustainability with a quality of life and capable of housing 225,000 people, while producing "negligible" greenhouse gas emissions. The company estimates that it will need to raise $10bn for the project.

The company plans to integrate IT into the fabric of the city, installing hundreds of thousands of sensors that allow an urban operating system to deliver intelligent buildings that are constantly optimized to enhance comfort, buildings that know to turn the air con up before you even realize you are hot, productivity and environmental sustainability. Meanwhile, the latest renewable energy technologies and green building techniques will allow the city to operate with a virtually non-existent carbon footprint.

Projected population growth means the world has to deliver between 9,500 and 10,000 new cities over the next 40 years to house everyone. There is no chance of avoiding dangerous levels of climate change unless this expansion is delivered in an environmentally-sustainable manner.