In Portland, Going Green and Growing Vertical in a Bid for Energy Savings

Going green to save energy is expensive; may take a long time to
recoup costs.

In Portland, Going Green and Growing Vertical in a Bid for Energy
Savings

The federal government plans to plant a bold vertical garden with
"vegetative fins" that will grow more than 200 feet high on the
western façade of the main federal building.

http://s.nyt.com/u/tN3