In North America, there are many ways to “live green” – you can compost, recycle, install compact fluorescent lights. But perhaps the ultimate in green living is the “Earthship”. Designed by Earthship Biotecture in New Mexico, Earthships are the “epitome of sustainable design and construction”. They are typically off-the-grid and leverage available local resources.
To elaborate, Earthships are homes made from natural/recycled materials and powered by solar or wind energy. External walls are often built from earth-filled tires and internal walls from recycled cans joined by concrete. To regulate the temperature, Earthship walls are thickly plastered and roofs are heavily insulated. Windows along sun-facing walls maximize solar heat (and light), while natural ventilation and contact with the earth assist with cooling.
For water, earthships collect rooftop water and pass it to a cistern for filtration. Once clean, the water is pumped throughout the house—except to toilets, which are filled with “greywater”. Greywater is produced by passing used water (from the shower and sink) through a botanical cell. Composed of plants and gravel, the cell can also be used for food production. Water from toilets is sent to solar-enhanced septic tanks.
This design contributes to a remarkable zero carbon footprint. During construction, the transportation and use of local materials produces low carbon emissions. However, the emissions are offset by the use of recycled materials (45% of the home). These materials have a negative carbon footprint because they eliminate the need for waste processing and the production of new materials. Furthermore, by using renewable energy and heating/cooling without fuel, the home’s operation produces no emissions. This zero carbon footprint compares to CO2 emissions of 110 tons/year for the average American household. Combined, emissions from homes account for 17% of total US greenhouse gas emissions.
So what is the catch – high costs, rigid building parameters, lengthy construction periods? In fact, “Earthships cost about the same as a conventional home”. The Global Model, for example, costs approximately $225 per square foot, with construction drawings ranging from $5,000 – $10,000. These costs drop by almost 40% when the owners build the home themselves. Furthermore, the Global Model can be customized for almost any climate and size, and can be built by the Earthship crew in only one month.
Want an Earthship – or inspiration for your own home? Visit: www.earthship.com.
Flickr photo credit: RONg