Doha expert develops device to cut CO2 emission

The concept of the shading device was submitted by Martin Hay, Architecture Manager at GHD’s Doha office, at the company’s innovation programme which received over 6000 novel ideas. Hay’s concept was later developed and tested in collaboration with the company’s Brisbane and Melbourne offices.

“The external shading system sits like a skin on the outside of a building, moving around on tracks to shield the sun while still allowing daylight to penetrate. Made from a lightweight frame incorporating photovoltaic cells, the sunshield is capable of reducing the energy required to light and cool the building by 30 percent,” Hay said.

It can produce enough energy to power the movement of the shade and provide up to 10 percent of the building’s remaining power needs. The device is made from a simple and cost-effective series of modular panels, which can be removed individually without compromising the whole system; and incorporates a guide rail at each floor level to provide both structural support and access for cleaning and maintenance.

In the Middle East where summer temperatures can soar past 48C accompanied by weeklong dust storms, keeping homes and offices cool and well lit can consume up to 70 percent of the total power use for a building.

Hay said: “To create truly sustainable cities, shading needs to be an integral part of any infrastructure to reduce the need for air conditioning and lighting in the first place.

“Hot countries have traditionally regulated temperatures using a combination of anti-sun glazing, internal blinds and air-conditioning. However, blinds do not stop the heat from passing through the glass façade and being trapped within the building, and reflective glazing systems increase the need for artificial lighting.

“We have estimated that if you mounted the sunshade system on a 40,000 m2 tower, 40 floors high, the shade could reduce CO2 production by 600 tonnes and generate 1,000 Megawatt hours of power a year.”

The idea spiked interest in the construction industry after Hay presented it at a Building Materials’ Construction & Technology Congress in Kuwait City.

The sunshade concept has the potential to support sustainability objectives in the Middle East, as well as northern Australia, South East Asia, Africa and Central and South America.