UPDATED – The King Abdullah University of Science and Technology (KAUST) at Thuwal (near Jeddah) in Saudi Arabia was recently announced as one of the winners of the American Institute of Architects’ Top 10 Green Buildings awards for 2010.
The new international graduate-level research university was established by the government-owned Aramco, the world’s largest energy corporation, to drive innovation in science and technology and to support world-class research in areas such as energy and the environment. The campus project was designed by HOK Architects and was completed in September 2009.
KAUST’s new campus is Saudi Arabia’s first LEED certified project earning a Platinum certification, the highest rating in the United States’ green building rating system At 496,000 Square meters, the project also represents the world’s largest LEED Platinum project.
The design brief for this project was to create a contemporary work of architecture that would resonate with the global scientific community while being firmly rooted in the local Saudi culture. The brief also required the designers to produce a campus of the highest physical quality at an unprecedented speed. The brief was to develop the project from a concept to completion in just three years.
In addition, since KAUST’s research agenda included research into renewable energy, and considering its many partnerships with many leading universities with sustainability commitments, sustainable development also became an integral part of the campus’s design and operation. In fact, the Project’s design brief included clear instructions to create a low-energy, efficient, and highly sustainable campus.
The decision to include efficiency and low energy design into the design brief must be understood in its local and regional contexts. In Saudi Arabia, the cost of electricity is quite low (ranging between 2-4 cents/KWh) due to substantial government subsidies. This means that there is little financial incentive for building owners to save energy and that the payback period for many energy saving strategies implemented are too long for them to be economically feasible.
However, the decision taken by KAUST to create an efficient low energy campus was not about financial return, but rather to provide a campus that would serve as an example for environmentally responsive buildings in the region.
Design Inspiration from Traditional Middle East Architecture
In order to achieve these goals and to respond to the extremely hot and humid climate of the north Red Sea, the project team led by HOK Architects sought inspiration form the traditional architecture of the Middle East. These traditional inspirations included:
1. The compact planning of the traditional Arab cities of the Middle East.
This feature of bringing buildings closely together helped minimize the areas of the buildings facades exposed to the sun and encouraged passive ventilation between them. This shading and ventilation helped temper exterior microclimates which together with reduced outdoor walking distances, are both critical to fostering outdoor activities and interactions(Image 3).
2. The Traditional Souk,
Like the Souk, or traditional marketplace, which was often shaded and passively cooled and ventilated, the circulation thoroughfares within the campus are shaded and passively cooled. They are also characterized by dramatic natural lighting via their roofs and social spaces (Image 4).
3. The overhanging Arabic Bedouin tent
The project designers were inspired by the Bedouin tents to create a monumental roof system that spans across the campus’s building masses to block the sun from buildings’ facades and from the pedestrian spine. This helps to facilitate natural ventilation and to filter light (Image 2).
4. Traditional passive ventilation strategies of the traditional Arabic houses.
The designers of the campus were also inspired by the design of wind towers that encourage airflow in pedestrian walkways. The wind towers used are the solar wind tower, also known as the solar chimnies.
5. The traditional Mashrabiya
The Mashrabiya, or wooden latticework screen, inspired the design of the campus’s shading devices. Like the Mashrabiya, the design of the shades was both to filter the sun as well as create beautiful light and shade patterns.
Like much of the United States and unlike most European cities, Saudi Arabia is almost completely reliant on private cars as the primary means of transportation, with public transportation almost nonexistent. The project designers sought to create a campus that relied less on the car and more on pedestrian and alternative transportation systems.
The campus is located a mere 800 meters from the dense new city of 10,000 – 12,000 people allocated for faculty and researchers. The two zones are connected with shaded walkways thus giving students and faculty opportunities for biking and walking to the campus. In addition, KAUST also implements a comprehensive alternative transportation plan which includes public and alternative forms of transportation including bicycles, Segways, community-shared electric vehicles, and buses. Preferred parking for alternative fuel vehicles, secure bike racks, and shower/changing facilities all help encourage these alternative modes of transportation.
The site also included two major sensitive marine habitats which required protection: coral reefs and mangrove forests. These two habitats were protected from the impacts of development by establishing a 50 meter buffer zone that limits development and construction activity within the coral and mangrove boundaries. The surrounding ecosystems are also protected by treating storm water before it leaves the site and by capturing run-off pollution and sediment.
Furthermore, to mitigate the impacts of the heat island effect, especially given the intensity of the sun and solar heat gain in Saudi Arabia, light-colored paving materials were selected to increase solar reflectivity and decrease the overall outdoor temperatures.
The high temperatures and humidity levels of the site had tremendous effects on the project’s design strategies. The building orientations limited harsh eastern and western sun exposure. The harsh morning and evening solar gain from the northeast and northwest were also mitigated using appropriate shading of the corresponding facades.
But while the designed attempted to reduce sun exposure, it also sought to maximize daylighting to improve occupant comfort and to reduce lighting demand. The compact form of the campus, therefore, took the form of fingers with shallow floor plates, allowing natural daylighting to access all perimeter spaces well as a some of the interior spaces.
In addition to shading and daylighting, the campus design encouraged natural ventilation. A pre-design analysis of the wind direction in the northern Red Sea showed a consistent northwesterly wind direction with a speed of 6 m/s, however, a more detailed analysis of the site showed that its microclimate includes wind coming directly from the Red Sea in a northeasterly direction. The building’s solar orientation helped take advantage of prevailing Red Sea winds and to use wind as a cooling mechanism.
But perhaps the most interesting natural ventilation feature of the project is the use of two solar wind towers. These wind towers induced natural ventilation during the day even in the absence of wind by absorbing solar heat using a dark surface at the top of the tower. The hot dark surface heats the air around it which rises through an opening at the top of the tower, drawing cooler air from below to replace it. The air draw at the base of the tower creates air movement in the circulation spines connected to the tower. Computational fluid dynamic studies (CFDs) were carried out for the solar towers to optimize their design.
The use of the wind towers, also known as solar chimneys, together with the prevailing Red Sea winds helped create a natural ventilation effect that provides a high level of comfort throughout the year for people using the circulation spine areas, saving the need to condition approximately 1 million square feet.
Energy conservation and generation
After employing as many passive strategies as possible to reduce energy loads, the design team selected the most climate appropriate and efficient mechanical and electrical systems to further decrease energy demands. The design incorporated low energy cooling techniques such as chilled beams, heat recovery wheels, and displacement ventilation to reduce the cooling and ventilation loads. It also included high-efficiency lighting with controls such as daylight and occupancy sensors to reduce lighting use while increasing the productivity levels of occupants. These systems together with a campus-wide building automation system will help significantly reduce energy use.
In addition to therese energy conservation measures, the design also features renewable energy generation. The campus’s roofs are covered with large solar Photovoltaic arrays for electricity generation, as well as solar thermal arrays for heating domestic water. Together, the two systems produce a total of 7.8% of the energy requirements on-site. A further 70% of the campus energy load was purchased through Renewable Energy Credits. The campus’s overall energy savings is 27.1% (compared to ASHRAE 90.1-2004 standards), which is a substantial achievement given that the campus includes lab buildings that require high levels of process energy loads that reduce the overall energy savings.
Water conservation is critical in Saudi Arabia as well as in most of the Middle East. The average rain fall on the site of KAUST is a low 54mm annually, with much of this rainfall occurring in the winter season. Most of potable water use in Saudi Arabia is desalinated sea water, with Saudi Arabia desalinating more sea water than any other country. Given the scarcity of water and the high energy use associated with desalination, water conservation is perhaps an equally pressing issue in Saudi Arabia as energy conservation.
The design team implemented numerous strategies to reduce the amount of non-potable water needed to irrigate the KAUST campus. According to the campus’s comprehensive irrigation plan, all gray and black water is treated and used for irrigation. Native vegetation and adaptive plants were planted on site requiring less irrigation and therefore help reducing irrigation water demands. Efficient drip irrigation systems are also employed to reduce the amount of potable water lost to evaporation and runoff. In addition to irrigation water saving, other water-saving strategies have been incorporated to reduce the water demand by 40% by using low flow fixtures in the campus’ buildings .
Operations, Maintenance, and Post Occupancy Evaluation
In addition to the sustainable strategies incorporated into the design, KAUST will also implement a sustainable operations plan which includes using green cleaning materials and an extensive recycling program that includes composting of all food waste. All service vehicles for maintenance staff are electric vehicles to reduce their fossil fuel use. While the use of electric vehicles is questionable given Saudi Arabia’s fossil-fuel dominated energy mix, it represents a symbolic move and may be complemented with the installation of renewable energy powered vehicle charging stations.
As for post occupancy evaluation, the campus facilities management will implements plans to continuously assess the campus’s energy use and the occupants thermal comfort. Thermal comfort surveys will assess the effectiveness of mechanical systems, thus helping the facilities management to adjust the settings to ensure maximum occupant comfort. The campus’s automation system will also measure all energy and water use for the project with sub-meters and controls installed to allow for future increase in efficiencies of all systems.
Karim Elgendy is an architect and sustainability consultant based in London. He can be contacted at: Karim [AT] Carboun [DOT] com
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