High Performing Buildings - Winter 2008 - (Page 26)

I N T E G R AT E D W I N D P O W E R The Pearl River Tower’s wind design is based on a small turbine (almost 10 ft or 3 m in diameter) by English manufacturer Quiet Revolution. Each of the design’s four turbines has a rated performance of 10,000 kWh per year. SOM pulled in the largest wind engineering and consultancy in the world to help them with testing and modeling for the wind design — Canadian firm Rowan Williams Davies & Irwin Inc. (RWDI). RWDI’s models helped to size and place the turbines and provided suggestions to SOM for selecting turbines —considering maintainability issues, noise, and vibration issues. One of RWDI’s tasks was to model wind potential. Power potential for wind is a cubed relationship, Frechette said. Air is pulled through the building, accelerating the speed of the wind by more than two times — and increasing its power potential by a factor of eight. For this site, models showed that average wind speeds of 9 mph (4 m/s) will speed up to as fast as 18 mph (8 m/s) when they are sucked through the building openings. “In essence, one wind turbine located in one of the openings could theoretically produce the energy of eight turbines somewhere else,” said Frechette. “So, this building has power comparable to 32 turbines.” The turbines are estimated to provide 1% of the building’s energy needs. Pearl River Tower design was based on a turbine by Quiet Revolution. through the holes in the envelope by the negative pressure on the leeward south side, accelerating winds to speeds of about 18 mph. Modeling and wind tunnel testing show this design has a power potential capacity of nearly 15 times more than a typical stand-alone wind generator — in this case about 1% of the tower’s power needs. The design was based on using four small wind turbines manufactured by Quiet Revolution, which have a capacity of 10,000 kWh per year. SOM also is taking advantage of the tropical sun, using two kinds of solar electric panels on the east and west façades. At the crown of the tower, the design calls for photovoltaic (PV) technology integrated into more than 16,000 ft2 (1500 m2) of the façade glass itself. Another 16,000 ft2 (1500 m2) of PV will be mounted onto the ﬁxed solar shading feature on the west façade. In all, the tower’s PV technology will have a 300,000 kWh capacity 26 HIGH PERFORMING (about 2% of the building’s needs). The wind and photovoltaic systems not only reduce the amount of electricity needed from the power grid to operate the building, but also create a more efﬁcient system altogether. SOM’s initial design also included the capability of producing power on-site using microturbine technology. Conventionally, power generation starts at the power plant, sends electricity along lines to a transformer, and ﬁnally to the building’s wall receptacles. Energy is lost along every step of the way, making that energy pathway about 30% efﬁcient. Generating electricity at the site where it will be used reduces the losses that come from handling and distributing it. According to Frechette, the Pearl River Tower systems, with heat recovery, would be able to use about 80% of the energy that is produced, much more efﬁcient than “importing” electricity from the utility. Multipurpose Double Wall Façade With 71 ﬂoors of glass exposed to tropical sun, one key element to reducing cooling load and the energy associated with it is the façade itself. SOM and their Canadian subcontractor Rowan Williams Davies & Irwin Inc. (RWDI) used modeling and wind tunnel testing to ﬁnd the façade that would ﬁt the structure and design intent. Skidmore, Owings & Merrill LLP Four openings in the façade house the wind turbines and reduce pressure on the tower structure. BUILDINGS Winter 2008 Skidmore, Owings & Merrill LLP

Table of Contents for the Digital Edition of High Performing Buildings - Winter 2008

High Performance Buildings - Winter 2008
Passing On the Gift: Heifer International Headquarters
Head of the Class: University of Florida’s Rinker Hall
How Far Can You Go? Pearl River Tower
The Proof Is Performance: How Does 4 Times Square Measure Up?
Lighting the Way: Two Guilford County Schools
Montreal’s Retail Example: Mountain Equipment Co-op® (MEC)

High Performing Buildings - Winter 2008