Thursday, July 15, 2010

According to popular discourse, David Conrath has managed to meld tenets and technologies from "Planet of the Apes," ancient Egypt, an Antiguan monastery and 19th century prairie life into a sustainable formula that is catapulting Alexandria City Public Schools (ACPS) into the next generation, and the next, and maybe even the next.

Conrath, a free-associating kind of Captain Kirk of design and construction for ACPS, is ringmastering a sustainability makeover – or maybe more aptly a takeover – of ACPS’ 19 facilities, 17 of them schools. By his own admission, after four years at the helm, “…the road is littered with professionals – two or three civil engineers, an architect, and a couple of mechanical engineers – who didn’t get with the program and weren’t forward-thinking enough.”

In this case, the road to which Conrath refers is actually the asphalt parking lot that blankets TC Williams High School’s Minnie Howard campus. For the uninitiated, in Alexandria 9th graders are separated from sophomores, juniors and seniors, on their own campus, for what officials consider a pivotal year often fraught with transitional woes. While TC Williams High School was built a decade ago and achieved LEED Gold, the Minnie Howard campus was plagued by heating, cooling, and recycling failures, the detritus of the last energy crisis in the 1980s, and languished amidst mounting energy bills, insufficient classroom air and a Beatles-era Perkins diesel generator (what Conrath calls a “Planet of the Apes” scenario but which he has retained for emergencies “because the grid is pretty crappy in Alexandria”).

Hiring Dallas-based Energy Education Inc., a firm working with about 200 school systems across the country to facilitate energy modeling, according to Conrath, ACPS began by addressing the ‘80s answer to energy conservation. “In the 1980s, in our school system, they took out every fresh air intake for every classroom and bricked them up,” Conrath said, explaining that sometimes there’s an “unfortunate inverse relationship” between being green and indoor air quality – and energy savings. “To bring fresh air into the building costs a lot of money,” he added, noting that in order to save 16 percent of the energy bill back then, “not having to circulate, temper and condition fresh air was standard practice in the last energy crisis.” Unfortunately, the practice resulted in a lot of sleepy students and faculty, not to mention exceedingly high levels of classroom humidity and consequent “smelly, stinky problems,” according to retiring 9th grade teacher Mary Sue Garner, who said that even with an air conditioner, she had to keep the classroom door open.

Ground Beneath Their Feet

In a big picture effort to reverse the problem and address pervasive heating/cooling issues at Minnie Howard, and to align the school with 21st century sustainability, Conrath began the geothermal process by inventing methods to plant 64 wells, 310-feet deep, drilling through the asphalt parking lot without lifting it into the air (he admits the first couple of tries did just that). Drilling through the next layer - which was mud - ensued, as did tackling erosion sediment control and also installing a special muffling device so the work could continue throughout the school year. The job became a kind of choreography during the day, according to Conrath, because of the active bus loop meaning the work would have to start and stop and start again with an eye to bus schedules. The wells, which contain 10-inch diameter special piping with a silver nitrate lining (a natural biocide that precludes mold), would store air drawn in from the outside by a 10 kilowatt photovoltaic solar array, and keep it at a constant fifty-degree ground temperature. “If we draw in air at 95 degrees with 90 percent humidity (by the array), and it comes in at 80 degrees and 60 percent humidity, we get a 15-degree drop in temperature,” Conrad explained, noting that in winter, a 15-degree boost is expected. The solar array, in plain sight for educational purposes when you enter the parking lot (it also serves to shield southern exposure windows providing cooling for those classrooms), is linked to a variable zone refrigerant system, which serves to influence temperature even more when necessary.

Roof Over Their Head

With a green roof installed initially on a test basis on one-third of the footprint of the school, energy bills compared from a snowy, almost sunless January, 2010, to the same month of the previous year yielded more than $5000 in energy savings. A 5,000 sf green roof, visible from the road because of the way school is sited, is also projected for the school instead of the current tar roof, which will slow down storm water, filter and purify solids, and change nitrates and chemical properties of the water. It will also naturally insulate the roof, much like a 19th century prairie sod house.

“My first day on this campus I felt like Jethro Bodine in ‘The Beverly Hillbillies,’” Conrath quipped about the character who was always dazed and confused about creature comforts and accruing technology. “I was taking some time to wrap my head around the concept of putting Astroturf on the field and grass on the roof.”

Walls That Don’t Contain Them

In the bowels of the school, in what the crew of the Starship Enterprise might perceive as the command center (actually it’s the old mechanical room), the makings of a “Greenovation lab” emerge, a term coined by ACPS special projects assistant Grace Taylor. The kid-safe space replete with gauges, real time Web data, dashboards and other educational components will serve as an education center, maybe even imagination central, both for 9th graders and to entice some of the older children who have dropped out to return. The students will benefit from “green collar training,” or training in technology disciplines that don’t even exist right now like working with solar arrays, Conrath said, but which are “fast coming online.” In fact, at present, every system in every school can be directed from a laptop at Starbuck’s, Conrath noted.

Windows on their World

According to Conrath, among the many impetuses for the greening of ACPS was a series of incidents three years ago at John Adams Elementary School, located in an area where the grid is stretched thin. “We kept losing power and had to close the school,” Conrath said, “because there were no windows in the bathrooms.” Unable to afford an emergency generator, Conrath came up with a 21st century application of an ancient Egypt-based solution called a sun tunnel.

“While they didn’t have Fresno lenses and plastic in Egypt, the concept is the same where light is gathered through the lense’s multiple prisms (the lense is a small globe that sits on a white roof like a lighthouse),” Conrath explained. It is then sent down a mirrored tube into a 2’x2’ plastic light diffuser. “People never even knew there wasn’t a light in there,” he said.

At Polk Elementary School, seven emerging technologies including geothermal wells, a variable zone refrigerant system, solar renewable energy, photovoltaic energy, daylight harvesting, green roofs and an eco-air system grounded to the air/heat exchange system carry with them the distinction of making Polk the only elementary school in the country to merge these systems. The technology at Polk was used in the 1500s, Conrath explained, adding that he’d seen it exemplified at an Antiguan monastery where a catacombed basement was designed like a nautilus shell. When the wind blew, cold air from downstairs was rolled up through the monastery, exhausted and then emitted.

Citing a fiduciary responsibility to taxpayers and a dream way into the future to be off the grid, Conrath, who has a Masters degree in industrial design from RISD, said ACPS is trying to adopt Alexandria’s comprehensive Eco-City policy, implementing all of its projects. “It makes (progressive) San Francisco look archaic,” he said, noting the projects include water conservation, daylight harvesting, vegetative (or green) roofs and low-albedo finishes such as white roofs to reflect the heat. “As a school system, we’ve increased our footprint about 25 percent over the last 10 years but we’ve only increased our energy consumption by 10 percent,” he stated, with all that implies. “Nothing is as green as money.”

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