It isn’t hard to guess that Mayor Richard  M. Daley’s color of choice out of a crayon carton would be green, the color of energy-efficiency and a trend that could lead to Chicago becoming the greenest of all American cities.

About 6,000 trees have planted since Daley has been in office; 90 miles of median planters have been constructed; eco-friendly rooftop projects have been started, and now Daley’s newest accomplishment, Leadership in Energy and Environmental Design certification for all new public buildings.

“We don’t necessarily get the exposure of Portland, Ore. or Vancouver, but there is a very active [green] community here, and some of the best minds who are working on these issues in architecture, design and construction, are in Chicago,” said Ben Ranney, a principal of Terra Firma, an architecture firm that focuses on green buildings. “We also have very strong municipal leadership in this regard. Mayor Daley has made a big point of promoting environmental construction and I think he cares about it very deeply.”

The United States Green Building Council announced that Chicago has earned Leadership in Energy and Environmental Development certification for 88 public buildings, which puts Chicago at the top of the list, beating out Portland, which was 2nd with 73 buildings and Seattle, with 63 certifications. Examples of these green buildings include the West McCormick Place Building, 2301 S. Lake Shore Drive, and the new F.B.I. Headquarters, 2111 W. Roosevelt Road.

There has been some criticism of the LEED certification program since it started 11 years ago.

Erin Duncan, a real estate agent for Saffron Realty Group who specializes in eco-friendly realestate said, “Some people say it’s too expensive, but it is a non-profit third-party organization. The other criticism would be that it doesn’t follow up once a building is certified, which definitely was the case a few years ago. However, with the new version of LEED, they do require additional follow up.”

According to the USGBC’s Web site, LEED  certification is determined by the total points a building earns through a scoring system devised by the council. Points are given if the building is near public transportation, if it was built with sustainable resources, if the indoor air quality is good and if the building is energy and water efficient, among other things.

Larry Merritt, spokesman for the Chicago Department of Environment, said going green is a large priority for the city because it lowers costs, and it improves the quality of the environment in the city.

“What we found is that 70 percent of our gas emissions come from buildings, about 21 percent comes from transportation, so buildings are the largest area dealing with greenhouse gas emissions,” Merritt said. “It’s important that we address that through more energy-efficient buildings.”

Merritt said making public buildings cost-effective can potentially save taxpayers money within the next several years.

“There may be an initial increase in cost to implement some of these features, but the payback, whether it’s five years or seven years, it’s definitely worth it,” Merritt said. “When you look at the economics of it, and also the environmental impact, it’s a wise decision.”

Ranney said eco-friendly buildings are becoming more popular for both public and private buildings, including Walmart because it can save money through the reduction of utility costs every year and the improvements can keep employees healthy.

“There is research that has been published about worker productivity,” Ranney said. “[The research] proved through studies of workers who have been in green buildings that they are less likely to fall ill and they’re more likely to show up for work. There are also some intangibles that suggest people are happier and work harder when they work in a nicer environment.”

Ranney said private companies are also going green to boost their images for potential clients.

Duncan said green improvements are not just happening in public commercial buildings. Construction is also taking place on a smaller scale in private commercial businesses and people’s homes. However, the green advancements in residential buildings are less publicized and often overlooked because they haven’t reached complete LEED certification.

Jaemi Jackson, a Chicago LEED accredited professional, said Illinois and the federal government offer tax rebates on a lot of the sustainable products to promote green buildings. She said environmental improvements can also add value to buildings.

Duncan said potential home buyers cannot always afford to buy a fully remodeled, eco-friendly home because of the value the improvements add.

“Another option a lot of people are thinking about right now is buying a place that currently doesn’t have as many green features and retrofitting it into much more of a green home,” Duncan said. “That seems to be something that people are really comfortable with doing right now. Doing [green improvements] as a long term project rather than buying something that is finished out and ready to go, you can split those upfront costs.”

These improvements are normally small and revolve mainly around buildings with sustainable materials that use energy-efficient appliances.

“No matter how small the [green improvements] that people are making right now, everyone wants to do what they can,” Duncan said. “You do have to make a bigger investment, but of course over time, everything as far as the energy efficient features catch up and you end up saving money. It usually takes several years to do that, which is kind of the tough part right now.”