However, few companies have taken on the net zero challenge in the commercial office space, where there are more complications.

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When you factor in some of the other common expenses like expensive commercial office space, perhaps sky-high midtown Manhattan office space, along with expensive travel, and the costs quickly add up.

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Construction currently dominates the island, but it will soon be the location for more than 500, 000 square feet of commercial space, including office buildings and luxury shops as well as Rosewood Abu Dhabi, Cleveland Clinic and a Four Seasons hotel (planned to open in 2013).

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It also owns a 41% common equity interest in PS Business Parks ( PSB), which owns and operates commercial space, primarily flex, multi-tenant office and industrial space.

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It also owns a 41% common equity interest in PS Business Parks Inc. ( PSB), which owns and operates commercial space, primarily flex, multi-tenant office and industrial space.

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Construction on 260, 000 square meters of office, commercial, residential and hotel space is to start in 2001 and be completed in two phases by 2007.

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He said: "We have to rethink and redesign what our city centres are all about - and the city centre of Newport has taken a brave step in saying that maybe it's not just about retail, that it's not just about office space - it's about this kind of mixed activity, so dwelling spaces as well as commercial spaces".

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