ENERGY STAR manufactured homes and utility performance
ENERGY STAR's manufactured-home specification sets a measurable floor: a certified home must be at least 10% more energy efficient than a home built to the federal standard. That relative benchmark is not a promise that a resident's bill falls 10%. It covers the home as designed and certified, not a park's later maintenance.
The specification assigns the result to insulation, air sealing, ducts, windows, lighting, and heating and cooling. The unit is modeled home energy performance, the geography is the U.S. certification program, and the period is the current specification. The source does not publish a park-level sample size or controlled utility-bill experiment, so it cannot establish actual savings at one address.
Utility records answer a different question: what happened at one home in one period. Compare weather, occupancy, fuel, rate conditions, and billing days before attributing a change to a heat pump, envelope repair, or HVAC replacement. A VA can record kWh, therms, degree days, work orders, and vacancy periods; an owner or qualified contractor should interpret the result.