Earthships: bastions of sustainability or green-washing parading as a lifestyle? It’s hard to say. The intention and design of the Earthship model is a venerable one, and these sustainable homes are remarkably successful for many. However, there are drawbacks to living in Earthships, which many say are far less sustainable than their originators claim. So, would building Earthships on the Big Island be a momentous step forward for agriculture in Hawaii? Or would it be a floundering attempt to implement an unrealistic model of sustainability?
As more and more work exchange projects and community living arrangements emerge around the construction of Earthships, their viability is becoming an increasing matter of concern. And this is especially true for agriculture in Hawaii, as island resources are finite. Today we explore the benefits and drawbacks of Earthships, and why they may or may not be a progressive contribution to agriculture in Hawaii.
The Origins and Intentions of the Earthship
So, what exactly is an Earthship? In simple terms, it is a self-sustaining home made of natural, recycled, and predominantly local materials and supplied with renewable energy. The architect Michael Reynolds founded the concept in the 1970’s in New Mexico, where he first began experimenting with the Earthship model. In 1972, Reynolds built his first Earthship out of cans, bottles, and tires—the materials that remain an integral facet of the standard Earthship model today.
Reynolds conceptualized the Earthship as an element of what he called “radically sustainable living.” For Reynolds, radically sustainable meant completely off the grid and self-sustaining. He also wanted that model to be accessible to all socioeconomic classes. His model is thus predicated not just on principles of sustainability, but also on affordability and simplicity. The idea? Earthships would only gain traction and change the world if the average person could afford to and was capable of building one.
Reynolds went on to found the company Earthship Biotecture, which constructs Earthships for about $225 per square foot. They also sell power-organizing modules and other parts necessary for building an Earthship independently.
Earthships and Agriculture in Hawaii
Gardens and planters are integral facets of Earthship construction, rendering the structures a potential asset to agriculture in Hawaii. The Earthship can only be truly self-sustaining if it is able to support food production. Indoor and outdoor planters incorporated into the Earthship model are intended for that very purpose. Some people even add on chicken coops for eggs and meat, or fishponds for seafood and even Aquaponic greens. Greenhouse attachments are also common additions to the Earthship model.
Earthship Construction
Most people build Earthships out of recycled cans and tires. The walls of the exterior are constructed with tires, which are packed with earth for solidity and temperature control. To create them, one person shovels dirt into a tire while another sledgehammers and compacts the material. Each tire, once packed, weighs about 300 pounds. It is therefore most efficient to ram the tires in place, as they are difficult to lift. Builders then cover the tires with concrete. They also cover the thinner interior walls made of a “honeycomb” of cans. They sometimes cover these tin can walls with adobe, so long as they are non-load bearing.
Builders typically construct the home in the shape of a horseshoe, with windows at the base of the “U” facing north to produce heat via sunlight. Insulated roofs increase the efficiency of the Earthship’s solar energy sources.
Because the tires are earth-rammed, they don’t burn, thus reducing fire hazard relative to your average American home. They also reduce needless landfill waste, as we generate over 250 million scrap tires annually in the United States alone, and even more tin cans.
Modulating Internal Temperatures
The thick, earth-rammed walls are, in theory, thermo-regulating, as they absorb heat during the day and release it at night. Sun-facing windows provide thermo-solar heating. The light they allow to enter is supposed to stabilize the internal temperature at about 70 degrees Fahrenheit.
While these windows effectively heat the home on sunny days, data reveal that not all Earthships stabilize at comfortable temperatures. Hot days can produce temperatures up to 90 degrees in the north-facing rooms closest to the windows. South-facing ends of the house, on the other hand, may hover closer to 65 degrees. And on cloudy days, the whole Earthship can become unbearably cold.
Sustainable Energy
The Earthship’s thermo-solar heating mechanism is not the only means of sustainable energy production that the Earthship affords. Earthships also provide solar and wind electricity, rain catchment systems, and self-contained sewage treatment.
The primary mechanism of water procurement is a rain catchment system located on the roof. Rain that falls on the roof fills a cistern that, in turn, fills a water-organizing module that filters the water, supplying the entire house. This filtered water is safe for drinking and typically supplies sinks and showers. Grey water, or the water used in the shower or for dishes, can then become water for indoor plants and edibles, and also for flushing toilets.
Flushed toilet water becomes black water. The anaerobic digestion that occurs in the Earthship’s septic tanks, which are sun-heated via an equator-facing window, separates solid waste from the black water. Dwellers use the black water to water outdoor, inedible plants. Be recycling precious water, these water systems could be great for agriculture in Hawaii during dry seasons.
Deep cycle batteries harness and store power from exterior wind turbines and solar panels. These batteries are capable of powering the whole house, provided you are mindful of your use of lights and electronics. A power-organizing module converts stored energy from the battery into AC.
Though Reynolds intended for the Earthship to be self-sustaining, they are not necessarily designed to power the modern lifestyle, as it would be both inefficient and ethically contrary to the founder’s sustainable intentions. The thermo-solar power of the north-facing windows does reduce the demand on solar panels.
Benefits of the Earthship
There are several benefits of building an Earthship. The primary benefit and overall objective is to create a hospitable environment that is energy-efficient and good for the earth. Living in an Earthship also means no mortgage payments, utility bills, or gas, and a good deal of creative aesthetic freedoms.
The simplest, independently built Earthships can cost little as $20,000 to construct. Nicer Earthships are still relatively affordable, around $70,000. Finally, being able to grow food will not only save you; it will also bolster agriculture in Hawaii as a whole by promoting a larger shift toward sustainable, locally grown food.
Drawbacks of the Earthship
There are, however, several drawbacks of the Earthship, especially for agriculture in Hawaii. While many aspects of the Earthship look great on paper, they don’t necessarily pan out in all situations or climates.
The first and most relevant concern is the environmental sustainability of the house. Though it is made of recycled materials, it is not necessarily environmentally friendly. Concrete, for example, consumes oxygen and emits greenhouse gases. As the tires in the walls decompose, they, too, will release toxic gases, which could potentially become trapped in the Earthship. Because Reynolds designed the Earthship to function in arid New Mexico, these houses don’t necessarily operate effectively in humid places like Hawaii. Mold and algae are common and dangerous complications for Earthship dwellers.
They are also typically more expensive than most independent builders anticipate. A functional, barebones Earthship costs about $150 per square foot. Those costs don’t account for the time and energy you will spend to collect cans and tires. It can also be incredibly hard to obtain a loan or mortgage to cover the costs of building an Earthship.
Many people also find that the dream of complete self-sufficiency is not a reality for Earthship dwellers. Unless you live in a climate that generates at least 11 inches of rain annually that hit the ground, you will have to purchase water. It is also very unlikely that your Earthship will also be able to provide for all of your dietary needs.
There are several, smaller concerns that Earthship dwellers typically espouse. These range from the noisy pumps to spotty temperatures, from infestations to water damage. Thus, building an Earthship for agriculture in Hawaii requires a low maintenance attitude, careful construction, and functional adaptations.
