The state government is offering a small sweetener to encourage buyers of manufactured homes to upgrade to a model with the Energy Star federal efficiency rating.

The N.C. State Energy Office said today it would provide a $500 rebate to buyers of Energy Star manufactured homes. Such homes are built with superior insulation and materials to cut energy costs by an estimated 15 percent.

The incentive program is designed to increase demand for Energy Star manufactured homes, which cost slightly more to build than a less efficient home. A manufactured home is prefabricated off-site and delivered for assembly, rather than built on site.