Pearl River Tower

Pearl River Tower is a 71-storey office skyscraper in Tianhe, Guangzhou, China. It is about 309.6 metres tall. Ground was broken on 8 September 2006 and it was finished in March 2011. Skidmore, Owings and Merrill designed it, with Adrian Smith and Gordon Gill as the architects. China National Tobacco Corporation occupies part of the tower.

It is called a clean technology skyscraper because it was designed to use as little energy as possible. Its curved shape guides wind into openings at two mechanical floors, where wind turbines turn. The designers aimed for a zero-energy building by using ideas such as radiant cooling, solar panels and a double-skin facade.

Four steps to save energy

The designers used four steps: reduction, absorption, reclamation and generation. Reduction uses things like low-flow ventilation and high-performance glass. Absorption uses wind turbines and solar panels built into the building. Reclamation reuses heat from exhaust air. Generation aims to make enough electricity on site with small turbines. The goal was a zero-energy building.

Catching the wind

The shape of the tower funnels wind through four large turbines. They can produce up to 15 times more energy than normal free-standing turbines. The wind then goes into the tower's ventilation system. The widest side faces the wind, since in Guangzhou wind comes from the south for 80 percent of the year and from the north for the rest. This helps the turbines catch as much as possible.

Staying cool

Guangzhou is hot, so cooling is vital. Radiant ceilings cool the offices. The building has a double-skin facade, where an outer layer lets in solar heat and an inner layer blocks it, with a ventilation corridor in between that the layers adjust automatically. Lights come on only when needed, and curved ceiling panels spread light evenly, so less power is needed.

On the globe

The model shows the curved glass tower with openings where the wind passes through. Look at the smooth, bent front.