Rising new One World Trade Centre to push the envelope in green building design

  • One WTC showcases eco-friendly construction and operations methods
  • Among the largest fuel cell installations in the world; waste steam recycled

One WTC has set a new level of social responsibility in urban design with its architectural, safety and environmental standards (photo credit: WTC)

New York’s One World Trade Centre (One WTC), which is part of a 6.4-hectare complex now being built to replace the World Trade Centre Twin Towers and other buildings destroyed in a terrorist attack on September 11th 2001, will be one of the most environmentally-sustainable buildings in the world when completed in April 2013. 

Designed by architect David Childs of Skidmore, Owings and Merrill, LLP, One WTC will be the tallest building in the US and one of the tallest in the world. It is also said to have set a new level of social responsibility in urban design with its architectural, safety and environmental standards. It will also achieve the US Green Building Council’s LEED (Leadership in Energy Efficient Design) Gold Standard.

One WTC and the complex will feature these green elements:

Fuel cells: Twelve United Technologies Corporation (UTC) Power PureCell Model 400 fuel cell stacks will provide 4.8 million watts per hour of clean energy. This will be one of the largest fuel cell installations in the world, according to UTC.

Waste steam recycling: Waste heat from the fuel cell system will be reused for hot water and heating in the podium and the entrances, amounting to 70,000 BTUs of high-grade heat and 500,000 BTUs of low-grade heat. Alternatively, with the addition of an absorption chiller, the waste heat can produce about 50 tonnes of cooling for the building, reducing power needs from the grid.

Recycled rainwater: Rainwater will be reused for the cooling system and fire protection, and irrigation for the complex’s extensive landscaping. Rainwater – 60 inches annually in New York – will be stored in high-efficiency evaporative cooling towers located on site.

Central chiller: Air-conditioning will be supplied, in part, by a highly-efficient 12,500-tonne Central Chiller Plant (CCP) that uses water from the Hudson River to cool the WTC transportation hub, National September 11 Memorial and Museum, retail space and some non-commercial areas. The plant will circulate more than 113,500 litres of river water every minute.

Fresh air: A high-tech system will monitor indoor air quality. Carbon dioxide monitors will control ventilation and make the building healthier. If the monitors sense more carbon dioxide than is healthy, they send a signal to the air handler software, telling it more fresh air is needed in that space. The system then automatically increases the fresh air mix in the area. The buildings contain over 3,000 points of monitoring, according to Eduardo Del Valle, director of design management at One WTC.

Daylighting: When natural daylight comes through the windows, dimmers will automatically lower the interior lights. Every space within 4.5 m of the building’s facade will be equipped with dimming devices. The buildings’ windows also use ultra-clear glass, which allows light in but blocks excess heat.

Low-water bathrooms: High-efficiency plumbing systems will save 30% on water consumption compared to a typical building of its size. Low-flow toilets and devices will limit water use for hand washing.

Green port-a-potties: During construction, workers used composting toilets instead of portable ones that use chemicals. Waste mixes with other decaying biological products to create nutrient-rich soil. After workers make their “deposits”, the solid waste is channeled into a container half full of sawdust and worms. The urine evaporates, leaving only a film of biological material. These toilets are also smaller and easier to move than large chemical portable toilets, an important feature for toilets high in the sky. Once human waste is processed, more than 90% of it is re-used.

Landscaping: The new main plaza of the complex will feature more than 400 trees, all of which were harvested within a 800-km radius. The trees’ roots will help keep temperatures regulated in the museum that lies below.

Waste material recycling: The building site is recycling about 80% of waste materials, exceeding its own target by about 20%.

Recycled building materials: The new WTC is 75% “old”, at least in terms of materials. Everything from its gypsum boards to ceiling tiles contains a minimum of 75% post-industrial recycled content. This reduces its eco-footprint.

No cement: One WTC was built with “green concrete”, which will save about 12 million pounds of carbon dioxide emissions, 8 million kWh of energy and 113,500 litres of fresh water. (Green concrete, however, contains coal fly ash, which is environmentally challenging.)

Renewable energy sources: The facility will make use of off-site wind and hydropower.

Clean diesel: Construction contractors can only use ultra-low sulphur diesel fuels or “clean diesel” to reduce nitrogen oxide and particulate emissions in and around the construction area. All construction vehicles are equipped with extra particulate filters to further reduce their environmental impact on air quality.

No VOCs: Materials that contain VOCs – volatile organic compounds – are banned.

Save the ozone: Builders have barred the use of ozone-depleting hydrochlorofluorocarbon (HCFC) refrigerants in the building’s mechanical systems.

Sustainable wood: Half the wood used in the building was sourced from Forest Stewardship Council-certified (FSC) forests.

Mass transit: Workers commuting to One WTC will have unprecedented access to mass transit service from the new complex. New climate-controlled corridors will connect the skyscraper to the WTC transportation hub, the new PATH terminal, 11 NYC Transit subway lines, the new Fulton Street Transit Centre, the World Financial Centre and ferry terminal, underground parking, and retail and dining facilities. 

Construction of One WTC is heavily in progress and expected to see completion by April 2013 (photo credit: Joe Woolhead/Silverstein Properties)

Fast facts on One WTC

As New York City’s tallest skyscraper, its antenna tower will rise to 1,776 ft as a symbol of renewal and hope, also commemorating the US’s year of independence

It will have 3 million sq ft of office space on 71 office floors

The designer intends the building to derive about 35% of its power from renewable energy sources. Once the building operates fully, it is expected to draw as much as 70% of its power from green energy

Its safety systems exceed code requirements and include elevators housed in a protected building core, a protected tenant collection point on each floor, dedicated stairs for firefighters, concrete-protected sprinklers, emergency risers and communications systems plus enhanced communication cabling.

Adapted from information on www.panynj.gov and “Green facts about New York’s New One World Trade Centre” by Tracey Schelmetic on news.thomasnet.com