For the most part, companies offering energy audits are reputable and legitimate and will help you both save money and reduce your carbon footprint if you follow their advice in regard to upgrades. Your local electric cooperative or heating and air conditioning contractor are a good place to start for advice on energy auditing services in your area.
The DOE’s energysavers.gov website has guidelines to help homeowners conduct their own do-it-yourself home energy assessments. For instance, DOE recommends that homeowners make a list of obvious air leaks. The potential energy savings from reducing drafts in a home can be as high as 30 percent per year.
You should also check filters on heating and cooling equipment to see if they need to be changed. And if these or other appliances are over 15 years old consider replacing them with newer models that meet federal EnergyStar efficiency criteria. Also, swapping out older incandescent bulbs in light fixtures with higher efficiency compact fluorescents is an easy do-it-yourself project.
A professional energy auditor with dedicated assessment tools and the knowledge of how to use them will carry out a more comprehensive assessment than you can do yourself.