With its unusual design Taiwan's first carbon neutral building opens, and it has been nicknamed by security guards in the area as "Noah's Ark" partially due to its unusual roof. Y.S. Sun Green Building Research Center has a roof that has two solar chimneys, a natural roof garden, sun-shielding awnings, a wind turbine tower, and a leaf-shaped solar panel. The architect for the building is National Cheng Kung University's Lin Hsiente, who drew inspiration for the building from Noah's Ark, seeing it as a green refuge.
"One of the biggest misconceptions about green building on the market is that green building is high-tech. The solar power and green building our research team is promoting relies on ordinary and inexpensive technologies and locally sourced materials to achieve high efficiency," Lin told the Central News Agency.
The result is that this 4,800 square-meter" Magic School of Green Technology, "the building's name before it was recently given a more formal name by its main corporate sponsors, cost roughly NT$130 million (US$4.41 million), or NT$27,000 per square meter, to build, no more expensive than a typical low-rise office building.
So how efficient will this Noah's Ark be? Power efficiency is often measured by EUI (energy use intensity), which divides the total energy consumed by the building in one year by the total floor space. Low-rise office buildings in Taiwan have an average EUI of 125 kwh/square meter, but simulations done by Lin and his team suggest that this office building will have an EUI of 43 kwh/square meter, saving roughly 65 percent in power.
To make the building carbon neutral, NCKU agreed to plant trees on a 4.7 hectare piece of land on one of its campuses along Taiwan's coast to absorb and offset the carbon emissions produced by the building's energy consumption.
The key to the building's efficiency lies more in its design than actual high-tech gadgets. Lin's main weapons in the project were natural ventilation with the help of a solar chimney, a technology that has been around since at least the days of the Roman Empire, and ceiling fans.
"We designed a natural ventilation system so that the building's 300-seat auditorium does not have to be air-conditioned at least four months of the year. From what I've seen so far, the results have been really good, and we might be able to do even better than that, "Lin said.
Taiwan's muggy, humid climate almost dictates that packed auditoriums have to be climatized for comfort year round, but the NCKU green building avoids that when outdoor temperatures fall below 29 degrees Celsius by drawing cooler outdoor air into the auditorium through outside vents.
It then flows from below the stage up through the sloping seats to the back of the room, where it is then sucked out by the solar chimney located behind the solar panel on the roof.
The pull is created by the sun-heated chimney, with heat concentrated in a black aluminum panel inside the chimney that helps draw out the conference hall's hotter air.
Lin's simulations show that the draft of just below 0.5 meters/second will be able to turn over the air inside the auditorium five to eight times each hour, keeping it comfortable enough to avoid the use of air conditioning even during muggy spring and fall months.
Ventilation in the building's offices operates on the same principle. Each office has windows facing both outside and toward the inner atrium. That generates a cross-flow helped by slow-moving ceiling fans. Hotter air that flows into the atrium is then drawn through the chimney seen in the roof garden.
Other design features that limit power usage include limiting the size of windows to around 25 percent of the building's wall surface, using awnings that keep the hot summer sun out but the light from the lower-angled winter sun in, and using energy efficient lighting, without high-tech controls.
Click on the link above for the photo of the building, it is worth seeing.
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