$18bn mega-project is billed as one of the most sustainable cities in the world
Billed as one of the most sustainable cities in the world, construction of the 6km2 Masdar City began in 2008. One of the five integrated units under the Masdar umbrella, backed by Mubadala, Masdar City is an emerging global clean-technology cluster where current and future renewable energy and clean technologies are showcased, marketed, researched and developed. With the potential to house up to 40,000 residents and 50,000 commuters when fully built in 2025, Masdar City will also be home to the International Renewable Energy Agency (IRENA) and the Masdar Institute of Science & Technology (MIST). The anticipated cost of the entire development is $18bn to $19bn.
Every aspect of the city’s urban planning and architecture has been approached with sustainability in mind, with a substantial focus on natural cooling in the way the city has been engineered. Streets are built to be optimally oriented on a southeast-northwest axis, thereby providing some shading at street level throughout the day. “We have done extensive wind engineering into thermal comfort,” explains Gaurish Wagle, urban planning professional.
Unlike normal city parks which are built as recreational areas only, Masdar City’s linear parks are scientifically placed so as to channel prevailing winds into the city, 38° counterclockwise of the north axis. Located throughout the city, they are intended to provide convenient, shaded oases for residents, workers and visitors, incorporating walking, jogging and bicycle trails, benches and other recreational facilities. “It is the principle of wind movement from a wider space to a narrower space. It gets flushed, making it cooler and healthier. There is a constant flushing of fresh air,” says Wagle.
The materials used for the building façades are designed for cooling purposes. Laboratory buildings are shielded with ETFE (ethylene tetrafluoroethylene) cushions that ensure almost no solar gain on the structures, as well as limiting the heat radiated on to the street. Windows not already shaded by adjacent buildings have louvres set to prevent direct sunlight from entering the building.
“Transportation is one factor and building efficiency another that is being constantly improved by providing adequate materials that minimise solar gain,” says Wagle. “GRC (glass reinforced concrete) panels form a cushion and reduce heat gain within the building envelope. It is a screen which shades the glass and acts as a buffer that reduces the heat gain on the wall so the building inside remains cool.”
Excluding the windows, the rest of the façade is wrapped in 90% recycled aluminium sheeting which has 6.7kg of embedded carbon per square metre of 2mm-thick sheeting, compared to conventional aluminium sheeting, which has 56kg of embedded carbon per square metre. A wind tower which rises 45m above the podium is a landmark of the MIST neighbourhood. Its height allows the capture of upper-level winds, which can then be directed to the square at its base. In addition, the square acts as a recreational space, housing cafes and restaurants which spill out on to it.
“When the temperature hits a certain level, the wind louvres open, suck in the air, and direct it down the tower. The temperature in the courtyard gets a bit cooler and more comfortable,” explains Wagle. While cooling is a significant focal point of Masdar City, the sun has played a huge role in its development. Masdar’s 10MW solar-power plant is the largest grid-connected plant of its kind in the Middle East. Constructed in 2009 at a cost of $50m, the 22ha plant comprises 87,777 polycrystalline and thin-film modules which work to provide clean energy to the MIST campus within the city, as well as Masdar’s temporary on-site offices, as well as some of the ongoing Masdar City construction activities.
“Overall the plant is energy-positive. Over a certain period, we are producing more here than Masdar City consumes. It is not always the case – at night, there is no power production, but ordinarily there is more production than the site consumes,” says Dr. Afshin Afshari, professor of practice and programme lead engineering systems and management. Excess is then transferred to the grid, but the plant is yet to provide a visible return.
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