Officials at mgm mirage’s citycenter project hosted a tour of the under-construction facilities to highlight the resort’s adherence to LEED standards during the the National Clean Energy Summit 2.0 in Las Vegas last month.

In an attempt to be a pillar of conservation, CityCenter has been equipped with the latest in energy efficiency, including floor-based air conditioning units, recycling facilities, limos that run on compressed natural gas and water fixtures that use less water without decreasing water pressure.

Air quality is also a major component of any Leadership in Energy and Environmental Design certification, and tobacco smoke in casinos poses a major challenge. To address this, rooms are sealed to help prevent the infiltration of tobacco smoke.

“Designing CityCenter with sustainable elements and practices reinforces its permanence and creates a healthier environment for our guests and residents, as well as for the 12,000 people who ultimately will work at CityCenter,” MGM Mirage CEO Jim Murren said.

CityCenter is scheduled to open its doors in December.