Toxic dust, stale indoor air, mold and formaldehyde. The California Air Resources Board found all of them in the least desirable place: California’s K-12 classrooms. 


A team of local design professionals have targeted portable classrooms, which the 2004 CARB report suggests are even more environmentally sketchy than traditional classrooms. 


Paul Byrne, a Carmel architect, started Green Apple Classrooms with a vision for greener and healthier schools. GAC’s portable units are designed to produce as much energy as they use (making them “net zero,” in eco jargon) and improve the ventilation, lighting, noise and toxic inputs that typically degrade the learning environments in standard portable classrooms.


Byrne started drafting net-zero portable classroom design in 2009 after hearing about President Barack Obama’s proposed $6 billion green-schools initiative. The Senate voted down the bill, but Byrne pushed forward – partnering with David Knight and Abe Stallcup, owners of the Pacific Grove-based mechanical engineering firm Monterey Energy Group; and Csilla Foss, principal structural engineer of the Howard Carter Association firm in Monterey.


Knight saw more than a market opportunity. “We all had kids in school, and they were all in portables a portion of the time,” he says. “And [those classrooms] tend to be not very nice.”


Standard portable classrooms, Byrne says, are about as energy-inefficient as it gets. Unlike enclosed permanent classrooms insulated by brick and mortar, portables are exposed on all sides and use cheap materials that provide little insulation. “In terms of ventilation and air conditioning,” Byrne says, “they are the worst metal boxes for energy.” 


GAC installs solar panels on the roofs of its portables, uses cool-roof technology to reflect the sun’s heat, and features a super-insulated building shell. “They become little energy producers,” Byrne says. “When they are not being used in the summer, they are sitting in the yard producing energy, and that energy is going back into the grid.”


GAC units are designed not only to be more energy efficient than typical portables, but also healthier for their occupants. The 2004 CARB report found that portables are more likely than traditional classrooms to have substandard health conditions due to inadequate ventilation, uncomfortable temperature and humidity levels, poor lighting and the use of toxic materials like formaldehyde. GAC aims to create a healthier environment with windows that take advantage of natural light, efficient heating and cooling systems, high-quality air filters, pressurizing systems and less-toxic materials. 


The company plans to install its first five units in the San Carlos School District near Redwood City on July 24. But GAC’s owners see a much bigger potential market. They cite a Collaborative for High Performance Schools manual counting more than 85,000 portable classrooms in use in California, with up to 4,000 new ones added each year.


GAC was one of three finalists in its category at this year’s Monterey County Regional Business Plan Competition. Although GAC didn’t take home the top prize, competition judge Alan Barich predicts it will be very competitive in the marketplace. 


“They upgrade the temporary portable classroom on a cost-effective basis. And from a green standpoint, GAC has potential,” he says. “People want clean.”