Hall County government announced a pledge last week to reduce its energy use by 20 percent by the year 2020 as part of its commitment to a federal initiative. Earlier this year, the Hall County Board of Commissioners accepted an invitation to join the U.S. Department of Energy’s Better Buildings Challenge, a program that connects governments, businesses and nonprofits in sharing methods to reduce energy use. According to the Department of Energy, commercial buildings and industrial plants account for 50 percent of the nation’s emissions of greenhouse gases.