parking garage. It currently has six levels of parking for 495 cars. Several levels of this building extend across Fannin Street and connect to 1 Houston Center. They include a x bracing where the tramway would have been and a patio. It sits on top of Houston's six-mile (10 km) tunnel system. In 1999 former Mayor of Houston Bob Lanier moved the office of his real estate company to 2 Houston Center. Landar Corporation, Lanier's company, leased in 2 Houston Center. In July 2007, a fire was set in the northeast corner of the 16th floor of the building. In 2008 Crescent and the nonprofit Environmental Defense Fund worked together for 10 weeks to cost-effectively upgrade 2 Houston Center. As a result, Crescent will install new lighting, mechanical, and office equipment systems that will reduce the building's total electricity usage by 11%. The new systems may save Crescent and the tenants of 2 Houston Center $400,000 combined each year, and carbon dioxide emissions would be reduced by over 1,300 tons per year. Crescent plans to reduce 2 Houston Center's electricity usage by 20% over a 10-year period beginning in 2008. The company anticipates that the reduction will save the company $700,000 per year. In 2009 McJunkin Red Man Corporation expanded its lease in 2 Houston Center to of space. The United States Postal Service operates a center in 2 Houston Center. In July 2011 the USPS announced that the post office may close. The Houston Downtown Management District is headquartered in Suite 1650. The Consulate-General of Japan in Houston is located in Suite 3000. The lobby of 2 Houston Center was used as a filming location for The Swarm back in 1978. 4 Houston Center 4 Houston Center is a office building. In 2001 the building was 97% leased. The lower levels of 4 Houston Center have the Shops at Houston Center. In 2001 RWE Trading Americas leased of space in 4 Houston Center for its United States headquarters. The firm had the option to lease an additional of space in the following 18 months. Candace Baggett, the president of the real estate firm Calibre Group, said that the building is attractive to firms which need space for energy trading firms since the building has broad floors, each with over of space. Energy trading companies typically have wide-open trading floors. Many office buildings have half of the amount of space