On the cusp of potentially explosive growth in home area networks that can help save energy, companies are rushing to cash in on what could be a trillion dollar-plus market. Market research firm OnWorld estimated earlier this year that there will be 20 million home area network-enabled households worldwide by 2013. In North America alone, the race is on to retrofit what Millenia Group chief executive officer John LaGrou estimates are 10 billion electrical outlets for home area networks. Surfing the waves of potential buyers, companies are taking different tacks. Some look to those fascinated with the Internet. Some cater to couch potatoes. Others bank on those with gizmo fixations. Google, for instance, is busy developing software to give residents remote and automatic control of countless electrical devices in their homes from the computer desktop. Control4 is marketing a home entertainment system remote control device for $595 to allow household energy management through a display on a big screen TV from the comfort of the couch. Other companies are focusing on “dashboard” displays mounted to the wall. However, Austin, Texas-based GreenSwitch is betting that simplicity will rule the day in the emerging home area network market. “I don’t stare at my wall,” remarked Greg Hood, co-founder of GreenSwitch. “When I’m on my computer, I’m working.” That’s why GreenSwitch is developing a system that allows people to minimize household power use when they leave or go to bed with the flip of one switch. “Simple is what works,” said Hood, noting that because of complexity only 10 percent of the people who have installed programmable thermostats have bothered to program them. “That was a dismal failure of the Energy Star program.” The GreenSwitch home area network technology is based on the ZigBee wireless communications protocol. To work, wall switches and outlets must be retrofitted with devices that can receive radio signals from the master remote switch to power up or power down. The household thermostat also must be replaced so it can be controlled by the master switch through radio signals. In addition, since it is compatible with so called “smart meters,” utilities can use the system to remotely control thermostats in homes to manage power load. LaGrou said the GreenSwitch system should cut energy use by at least 20 percent in most households. However, the company wants a third party, like a utility, to study how much energy the system saves in households. LaGrou said that meanwhile, the estimated savings is based on documented energy savings of 25 to 45 percent in the hotel industry in Europe and Asia, where the system is commonly used in rooms. Retrofitting the average-sized home costs about $850 to $900 and takes a little more than an hour, according to LaGrou. While GreenSwitch products are designed for the “do it yourself” market, the company is distributing them through dealers who install them at this early point in the development of the home area network market. In hotels, the room is energized when a guest inserts a card key into a reader after entering their room. The key remains in the slot when the guest is in the room. Upon leaving, the guest removes the key which cuts the power to the room. In 2006, GreenSwitch formed and applied the technology to household and small business use, LaGrou explained. The company makes the hardware for its system in the United States, including one factory in Southern California and another in Pennsylvania. GreenSwitch had an exhibit at the Governor’s Global Climate Summit earlier this month and hopes to qualify for utility rebates through the state’s energy efficiency program.