Energy Secretary Jennifer Granholm on Wednesday announced a series of new building energy code determinations that the Energy Department says will save $138 billion over three decades.

The department projected the new code determinations will save up to 4.7 percent on-site energy, 4.3 percent source energy, 4.2 percent carbon emissions and 4.3 percent in energy costs. The department projects the determinations would generate savings of $138 billion over the next 30 years for homes and businesses, or about $162 per residential unit a year.