Zero Emissions in the Desert New Tower Creates All Its Own Energy

By Frank Thadeusz

Part 2: Faith in German Engineering


The architects chose an ancient Persian architectural feature as their model. Hundreds of years ago, wealthy merchants erected wind towers on the roofs of their houses, an idea which was eventually exported to the Arab world. The buildings, which have now become tourist attractions, have a natural air conditioning system. Lateral openings in the towers suck in cool air like a chimney. The heavier cool air sinks down and displaces the lighter hot air, creating a comfortable temperature inside the living space despite the scorching sun.

Gerbers's design is designed to function in a similar way: The negative pressure created by winds breaking along the tower will suck the spent air from the rooms out of the building via air slits in the façade. The plan is for fresh air to be pumped into the interior of the building by means of a duct system at the same time.

Seawater will be used to pre-cool the air. Three large cooling units in the giant building's cellar will eventually lower the temperature to a comfortable 18 degrees Celsius (64.4 degrees Fahrenheit). Transparent ducts will channel the fresh air into spacious atriums and from there into the corridors and offices. The building's designers want to use high-quality steel ropes to suspend hanging gardens inside the air ducts, transforming a feature which is often regarded as an architectural blemish and hidden behind sheet metal in other buildings.

At the same time, the underground cooling center also cools the water in the pipelines running through the underside of each floor's ceiling. The system of tubes is designed to be a modern air-conditioning system which cools gently without unpleasant air currents.

However the most impressive feature of the building is that the operators of the tower will not need to use any electricity from outside sources. A 60-meter (197-feet) turbine on the tower roof and two photovoltaic facilities with a total area of 15,000 square meters (161,459 square feet) will produce sufficient electricity to meet the building's needs. Additional energy is provided by an island of solar panels with an area of 17,000 square meters (182,986 square feet), which drifts in the sea within viewing distance of the tower.

The excess electricity will be used to obtain hydrogen from sea water by means of electrolysis. The hydrogen is then stored in special tanks. At night, the energy facility uses fuel cells to generate electricity, keeping the tower working through the hours of darkness. In the daytime, on the other hand, highly reflective mirrors on the roof direct the sunlight onto a cone of light that goes through the center of the building and provides its various floors with plenty of natural light.

The Burj al-Taqa seems like the most recent example of a trend that has been observable for some time. In large cities such as Chicago, New York or Paris, environmentally friendly skyscrapers are being built that win ecological awards and apparently herald a new green wave in the construction of tall buildings.

But energy expert Mösle is unimpressed by his competitors. "They're constructing buildings that are just as inefficient as their precursors," he says bluntly. "We're not one, but two degrees better than them."

Of course, it is not completely certain that the giant pepper mill in the desert will really turn out to be a wonderful energy source. So far, the engineers have only tested the tower using computer simulations. The investors don't have any tangible proof if the tower actually works either. "They won't be able to check it in advance," Gerber admits.

But he feels confident the investors won't be disappointed. "They have the greatest faith in German engineering," he says.

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