The motion detectors also have an important role in energy efficiency, turning lights on and off. In bathrooms, they turn on hot water circulation pumps when people enter, turning them off five minutes after they leave. "We don't have that pump running 24/7," says Aaron Ewerdt, Solaris' vice president of technology.

It's Always Sunny in Florida

Solar energy plays a prominent role. Twenty-four solar panels usually return power back to the local electric company after the EMA finds more efficient ways to use it in the homes by, for example, activating swimming pool pumps. One EMA screen shows the amount of power currently generated by the panels, daily and cumulative kilowatt hours used, and carbon dioxide (CO2) emissions avoided.

Pirelli says he is surprised that even during the two worst months for solar (December and January), the meter on his home was still running backward, earning credits from the power company and entitling him to thousands of dollars in tax rebates. Ewerdt adds that the panels somewhat unexpectedly put out around 3,800 watts, not far below their theoretical maximum of 4,080 watts.

The water heaters are also solar, passively heating the water. Pirelli believes the energy and cost savings of the heaters are so clear-cut that the equipment should be mandated by law. A Solaris spokesperson says that in comparison, a typical, 60-80-gallon gas water heater emits two tons of CO2 per year, the equivalent of two cars driven 10,000 miles each.

Pirelli seems inclined to blend social consciousness with tech savvy. In addition to his home automation business, he started a project called the Arial Home Initiative to bring affordable, mass-produced, energy-efficient homes made of galvanized steel to Third World countries.

Low Tech That's High Tech

The homes' building materials also play big roles in energy efficiency. According to Solaris and Cribb, the Structural Concrete Forms, referred to less formally as the E-wall system and sold by Florida-based Efficient Building Systems, are the most critical part.

Rather than being used and taken off site, the forms stay in place after the concrete is poured into them. Each E-wall has a two inch thick layer of industrial, closed cell polystyrene insulation on the inside of the house, plus a thick concrete wall that acts as a heat sink. Solaris says this results in exceptional strength for the walls, but it prevents the inside of the house from getting too hot or too cool relative to the outside air temperature.

"It's an amazing system," says Pirelli. "The entire house is poured in one day. Every single wall is connected to the other, and it's all poured at one time." Cribb says his company is so impressed by the technology that it might begin using it in future homes.

"The attic space was designed as a closed system," Cribb says of an energy-saving technique his company used for two years before the Solaris project. "There are no vents. That eliminates the outside are from getting into the attic." Cribb explains that this design conditions the air in the attic, and provides a greater thermal barrier and structural integrity over the typical system. "Your duct work for the air conditioning is in this conditioned space, which is cooler than an unconditioned space. The air conditioning runs more efficiently."

Adds Pirelli, "The whole idea is to keep the thermal envelope so the heat never enters into the house, so you never need to turn on the air conditioning." Glued-on window film also keeps excessive solar radiation from entering the home, he says.