According to the US Energy Information Administration, residential buildings are responsible for 21% of energy consumption in America, while the construction and operation of buildings is responsible for 50% of the greenhouse gases generated by the country. And according to Edward Mazria, an architect from Santa Fe, New Mexico, architects have a lot to answer for.

Mazria gave up a lucrative career in architecture to establish Architecture 2030, a nonprofit organisation that aims to challenge the construction industry to halve carbon emissions by 2010 and to be carbon-neutral by 2030. He also travels the US in an effort to increase awareness and responsibility for the building sector's responsibility in the current environmental crisis. To this end, he's written a revealing and informative white paper titled "It's the Architecture Stupid".

Mazria isn't alone in his green housing crusade. Matthew Berman and Andrew Kotchen, partners in an architecture firm, consider themselves to be guerrilla soldiers fighting for a global cause, namely reducing the negative impact that housing has on the environment. In 2006 they won a competition to design a zero-energy affordable-housing development in cyclone ravaged New Orleans. Their project is currently under construction and consists of both houses and apartments that will be powered by solar panels and feature built-in rainwater collection systems. They are also designed to make the most of natural ventilation and will be constructed from prefabricated, sustainable materials.

In addition to their New Orleans project, Berman and Kotchen design custom-made, energy efficient homes for the wealthier members of society. As part of their environmentally friendly campaign they try to change the way their clients perceive status and space. While many of the more affluent members of society attribute wealth and success with the number of square feet they own, Berman and Kotchen try to persuade them that smaller is in fact better, and that they can have opulence, luxury and good design in a small space.

Wilfred Wang, one of America's more colourful and controversial architects, says that in order for builders to save the planet they need to stop building. He maintains that instead of designing new buildings, or knocking down existing buildings and replacing with completely new structures, architects should retrofit existing buildings to make them more energy efficient.

In response to the environmental and energy crisis, many green housing projects have been proposed or implements all around the world. In Las Vegas the Enchantment Way Development project was recently announced. The project is part of the US Green Building Council's pilot programme to introduce green building techniques and energy efficient design to the region. Part of the project will be devoted to creation of a Desert Tortoise Habitat and to protect indigenous desert growth.

Britain has its first entirely green housing estate project on the cards, with a proposed development in London's Docklands. The project will include wind turbines, rainwater harvesting, organic fruit and vegetable gardens, solar panels, a cycle club and a car pool club. Austria has its very own EcoCity, or Solar City that uses modern insulation material and solar panels to reduce energy consumption and unique urban planning that locates all city facilities and amenities with walking distance of each other. Australia has the Aurora housing project that aims to deliver 8, 000 energy efficient homes for 25, 000 people within the next 20 years. And even India is getting in on the action with Kolkata's Rabi Rashmi Abasan solar powered housing complex.

Many people believe that the current slump in the housing and construction market is exactly the boost that green housing initiatives need to propel themselves into the limelight and bring their advantages to the attention of a desperate public. A report from McGraw-Hill Construction and the National Association of Home Builders reveals that the green housing market is expected to grow from $12 billion in 2008 to between $40 and $70 billion in 2012. This suggests that green housing projects will soon surpass traditional construction methods in both popularity and profit margins.