Don’t expect to see windmills or giant solar panels on the top of any Hall County government buildings soon.And don’t think the Hall County Sheriff’s Office is about to start chasing criminals in the Toyota Prius.Regardless, the county is earning some national accolades from the U.S. Department of Energy for recent energy-efficiency and environmentally friendly initiatives.Based on its use of a $762,000 Energy and Efficiency Conservation Block Grant, Hall County government was invited to participate in the Better Buildings Challenge. The national initiative brings together state and local leaders, CEOs and university presidents who have made commitments to energy efficiency.The county’s approach to energy efficiency has largely been to retrofit its existing buildings with more cost- and environmentally friendly upgrades. Largely, the county focused on replacing old lighting fixtures with newer, more energy-efficient ones and with updating its heating, ventilating and air-conditioning units, said Ken Rearden, director of the county’s Public Works Department.“We implemented the easiest things that would give us the most bang for our buck,” said Rearden.That direction has allowed the county to go for the low-hanging fruit rather than investing in some of the more underdeveloped energy-saving equipment.As part of its invitation to the Better Building Challenge, some Hall County officials are traveling to a summit in Denver with other governments, colleges and businesses to share best practices.