Fast nearing completion in the heart of Bahrain is a dramatic building which will become the world’s first large-scale integration of wind turbines and a skyscraper.

The $93 million Bahrain World Trade Centre project involves two 50-storey, sail-shaped office towers - each 240 metres high - supporting three 29 metre diameter horizontal axis wind turbines.

“The towers and turbines were inspired by traditional Arabian wind towers which harness the wind energy from the onshore breeze,” said Shaun Killa, of the architects of the landmark towers, WS Atkins.

The wind turbines will work by harnessing the offshore breeze and providing a substantial source of renewable energy. This is predicted to be around 11-15% of the building’s annual energy requirements.

Each turbine will generate between 1,100 and 1,300 megawatt hours per year. In carbon emission terms this equates to an average of 55,000 kgC.

The towers will act as aerofoils, funnelling the breeze between them. The vertical sculpting of the towers is also a function of airflow dynamics, maintaining a near equal wind velocity on each of the three turbines for optimal operation and energy yield.

The designers used wind tunnel testing and computational fluid dynamic modelling to confirm the wind stream remains nearly perpendicular to the turbine even if the wind direction deviates up to 45 degrees

either side of the central axis. This increases the turbines’ potential to generate power

Tower power

Bahrain’s World Trade Centre heralds green skyscrapers

The towers and turbines were inspired by traditional Arabian wind towers which harness the wind energy from the onshore breeze

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while reducing fatigue on the blades.The project has been described as “blue sky thinking”

and WS Atkins said: “With this building our client wants to demonstrate Bahrain’s commitment to reducing demands on fossil fuel energy reserves.

“The complexity of integrating large-scale wind turbines into a building is not to be underestimated and the knowledge and experience we gain from this project can be shared with designers around the world.

“We believe that this building will be a significant influence on urban design and architecture for desert climates, instigating a shift towards a more sustainable mindset.”

The three wind turbines are being installed on 65-tonne bridges. Conventional bridge bearings including single-point bearings and rolling bearings transfer the load of the bridges to the building structure.

The frequency responses of the bridges, turbines and blades have been taken into account in the design to mitigate transmission of noise and vibration to the building.

The speed of the blades has been lowered to an optimum level compared to standard wind turbines. In addition, the sound insulation of the cladding adjacent to the line of the blades has been beefed up and the thickness of the glass near the wind turbines has also been increased.

As well as producing some of its own energy, the trade centre is the first project in Bahrain to procure a district cooling system. Chilled water will be pumped through the air conditioning system from an underground network of piping from Tabreed’s new facility.

The towers themselves are positioned on top of a three-storey sculpted podium and basement, encompassing a shopping centre, restaurants, business centres and car parking.

The trade centre is also a “smart” building incorporating the latest intelligent office technology with a number of systems that have yet to be implemented in Bahrain and some that will be a first worldwide.

For example, it will also be equipped with a structured cabling system that integrates smart features including all forms of surveillance, data, energy and other operating systems.

Security features include the latest in closed circuit television surveillance and monitoring, automated access for tenants to common areas, parking facilities and individual floors as well as the latest warning and response systems. The building will also provide tenants with crisis management, disaster recovery and business continuity services.

“The building’s smart features will set a new precedent both here in Bahrain and across the region,” said Claire Hughes, associate director of leasing and management agents, DTZ Bahrain.

For more details, visit www.bahrainwtc.com

Ireland’s Airtricity has announced the creation of a pan European sub-sea energy grid, called Supergrid, which will link a series of offshore wind farms from the Mediterranean to the Bay of Biscay, Atlantic, North Sea and Baltic Sea.

The Supergrid is designed to carry energy generated by wind turbines to suppliers and act as a transmission network to deliver electricity around Europe, making its power markets more efficient at energy trading.

Airtricity and its technology experts, ABB, began work on the Supergrid in September last year with the aim of designing a high-voltage AC/DC power network to link national grids and deliver power from offshore wind farms.

The scale of this undertaking means that, when fully operational, Europe will have access to wind energy at all times because the wind will always be blowing somewhere on the grid.

Airtricity last month also announced a $28 billion, 10 gigawatt offshore wind energy foundation project in the North Sea between the UK, Germany and the Netherlands – the largest offshore wind farm proposed for European waters which could power eight million homes.

Airtricity’s Chief Executive, Eddie O’Connor, said: “Europe needs a reliable, secure and environmentally friendly energy supply. Supergrid and the 10 gigawatt foundation project are practically and symbolically significant proposals and release to Europe its most abundant primary energy resource.”

Turbine power Supergrid