A sculpture made out of trash might be the way that Kathy Baur would describe her earthship home.

"To me the concept of using cans, tires, anything you can recycle and make look pretty again was such a low profile way of building. I fell in love with the total concept immediately," Baur said.

More and more people are buying into the principles of an earthship home: a home that relies on concepts of green building to balance economic needs and the environmental impact using traditional and modern techniques. Construction materials vary from old tires packed with earth and adobe walls to high-tech photovoltaic solar panels. The perfect earthship, according to its adherents, is one that is completely self-sufficient.

According to information about green building on the state Energy, Minerals and Natural Resources Department Web site, "energy efficiency is the most cost-effective way to reduce the consumption of fossil fuels and the resulting greenhouse gas emissions that lead to global warming."

Nationally, the site says, buildings contribute up to half of greenhouse gas emissions.

People in the Estancia Valley like Baur have committed to building homes that use fewer natural resources and require spending little or no money buying electricity or paying for water.

No place like home

On a sunny day in late November, Baur stood on her rooftop and surveyed the 40 acres of land that she owns in Loma Parda west of Mountainair.

Mountains and desert are about the only things that can be seen and about the only noise is the sound of a train whistle. It's a very solitary place.

About 15 years ago Baur sold her house, quit her job and moved to New Mexico from Denver to build a 2,500-square-foot earthship. She had read three books written by Michael Reynolds beginning with "Earthship: How to Build Your Own." Reynolds' concepts helped create a self-sufficient housing community made from recycled materials in Taos in northern New Mexico.

"I totally cashed in all my chips and just said, gulp, because I gave up an awful lot of material things. A house, a good job, retirement setup, the whole nine yards," Baur said.

Baur built her house almost single-handedly. She only hired technicians for complicated installations like the solar system and windows. She alone pounded all the dirt with a sledgehammer into 1,000 tires that form the structure of her home. Then she stacked the tires and placed them directly onto the ground. Some of the tires show through her mud or concrete walls. Gravity holds the tires, and her house, in place.

Before she built her house, she built a well house or what she calls the "Baur Tower." It's a circular structure that surrounds her well and pump. She catches water on her roof but only uses it for watering plants. Her drinking water comes from her well.

Baur designed her home to use gray water. She pointed to a long trough in front of her south facing windows. "It's a garden space that you fill up with rocks and dirt and put plants in there. Then the water comes from the sink and bathtub and goes across the channel, and goes into a well. Then it gets picked up by a pump and gets recycled back through a toilet well. That means the water is getting used three times before it goes to septic," Baur said.

Baur opened the door into a dark room with a table that held many batteries for her photovoltaic power system.

"In here is the electric system. These are 360 amp deep cell batteries. This is how the energy gets stored during the day from the direct current solar panels. At night it slowly dissipates," Baur said.

She doesn't really need to heat her earthship home, which is entirely off-the-grid. The temperature was over 71 degrees in the late afternoon last month. So warm in fact that Baur kept several windows open. The coolest her home has ever gotten is about 58 degrees. In fact last summer she built an overhang to shade her south-facing glass windows.

"Up in Taos they have to angle the windows. Down here it's so hot most of the time that you don't have to angle the glass," Baur said.

Saving energy, selling energy

On the other hand Bryan Pletta and Cristina Radu have built a house hooked up to the grid. Their house stands on a steep hill overlooking Cedar Crest. Although they live on a cul-de-sac, a forest of trees keeps them relatively isolated from their neighbors.

The two sell the electricity they produce with a photovoltaic panel system on their roof to the Public Service Company of New Mexico.

They also have a solar thermal system that uses flat plates to heat their 2,400 square foot home and their water.

After getting heated through the system the water is stored in a tank.

"The hot water is used in showers, sinks and laundry. It's also used to heat water that circulates through the floor in the radiant floor heating system," Pletta said.

But it's still necessary on cloudy days to have a boiler for back up.

They will know next month if they have built a truly zero energy home because their systems will have been in place for one year. A zero energy home produces as much energy as it consumes.

Two meters link the home to PNM. One meter measures how much electricity is created by the panels. The other meter measures the power that PNM is taking, said Susan Sponar, PNM resources and corporate communications.

"For every hour created we pay 13 cents. If they create more than they use, then the meter spins backwards and we pay roughly 9 cents per hour," Sponar said.

Pletta and Radu spent about $45,000 on their two roof systems.

They also made sure their home got the most out of a very cheap energy source — the sun.

"We integrated the home to the landscape and built it oriented to the south for passive solar gain," Pletta said.

And there is no cooling system.

"We do it with windows. Passive solar not only heats but keeps cool in summer," Pletta said.

Although they have a wood stove, "the house pretty much heats itself," Pletta said.

Pletta and Radu had their new house checked last month by Larry Gorman, from Building Energy Solutions.

Gorman busied himself one day last month at their home installing a temporary fan in a door to perform an airtightness test.

"I'm going to suck the air out of the house," Gorman said as he punched numbers into a laptop computer that was connected to the fan.

The test was the pressurized equivalent of a 20 mile-an-hour wind hitting all sides of the home and the roof, he said.

Before performing the test Gorman handed Pletta an infrared camera so that the homeowner could look for leakage.

Pletta walked around inside the house holding the camera up to his face and staring at the walls. Leaks appeared on the screen as black space. Airtight walls appeared on the screen as white.

The test at Pletta's house cost about $340. It gave the home a Home Energy Rating System (HERS) index rating.

Pletta also plans to get a certification through the Build Green NM rating system. Homeowners could also be certified through the U.S. Green Building Council's Leadership in Energy and Environmental Design (LEED) rating system.

The state Energy, Minerals and Natural Resources Department issues a tax credit to homeowners that qualify based on the certification level and square footage of the residence, said Susie Marbury, energy efficiency and green building administrator.

Pletta said he hopes to get a tax credit for about $10,000.

Building the perfect home

Christian Meuli lives in a house made out of geometric shapes.

Four-sided parallelograms make up the sides of his 950-square-foot home in Edgewood about one mile away from Interstate 40.

Thirty years ago at a show in Albuquerque, Meuli said he saw the home and liked it.

"So I bought it from the engineers who had built and designed it," Meuli said.

He built his kit-home on a 10-sided foundation with the help of some friends. He is still finishing it by putting mud on the inside walls.

"The 20 panels bolted all together in one day. We used regular tools and cut windows before we put it up," Meuli said.

The home was made at Zomeworks, an Albuquerque company founded by Steve Baer.

During the day the inside mud walls get warm when the sun hits them. During the evening they release the heat.

Meuli also has a high efficiency wood stove and a back-up propane tank. He collects wood from his 12 acres and dries it himself.

"I've never bought wood in 30 years," Meuli said.

His limestone floor also heats his home, enough so that he can walk around barefoot in the winter time.

The trick to keeping the house warm is to let the sunlight in, but don't let the heat back out, he said.

Meuli's house also has a 6,000-gallon cistern for collecting drinking water.

"The longer the water sits in the cistern, the cleaner it gets. The secret is to keep the sunlight out so that nothing can grow," Meuli said.

Worth the effort

Building an earthship may not be for everyone, but Baur, Pletta and Meuli all agree that even the smallest efforts can pay dividends, whether it's simply trying to reduce consumption or selling electricity back to the power company.

Because they wanted to use recycled products, save money on heating and electricity, or just live less extravagantly, these homeowners would all agree that the time and expense they used building their homes was worth it.

"Everything is paid for. I didn't have to get a mortgage. I didn't have to buy anything until I got to the roof. All it cost me was labor," Baur said.