Not a bad bargain. Though retrofitting your home for energy efficiency entails some capital expenditure up front, it can provide from 10 to 60 percent return on your investment per year.
All homes are candidates, no matter what their age.
In order to conserve energy, it's important to reduce wasteful use and, when replacing worn out appliances, to buy models that are as energy efficient as possible. Always check the Energy Guide labels when shopping for new appliances. Though they don't tell the whole story, they help you compare energy efficiency. Next to heating and cooling, water heating is typically the largest energy user in a home. Often you can substantially reduce hot water needs through water conservation.