(Milwaukee)--On this very gray day, green is the color of choice for the city of Milwaukee. It has the proud distinction of being a national leader of reducing its energy consumption by 10% in just a handful of years. The central library is a showcase behind the city's work at being better environmental stewards. According to estimates, it's saving close to $40 thousand a year in energy costs alone.

Some steps this national historic landmark has taken to get itself on a greener path include a green roof with solar panels, enough to power three homes a year. Then there are new florescent lights for the dome and LED lights in the rare books area not to mention the repairing of hundreds of steam traps.

The 115-year old library is actually part of a \"Better Buildings Challenge\" put forth by President Obama to reduce its energy use 20% by the end of the decade.