Sources

http://energy.gov/science-innovation/energy-efficiency
The website energy.gov is a government website that has a lot of information about how we use our energy and how it impacts us. It's very informative about how we use our energy and gives evidence such as facts and statistics to backup it's statements.It's goal is to inform people how energy is used threw out the USA.

http://eetd.lbl.gov/ee/ee-1.html
This website defines energy efficiency as "using less energy to provide the same service." It also shares information on how people can be energy efficient and gives different examples of things that help become energy efficient. The purpose of this website is to inform people about the benefits of becoming energy efficient.

http://www.greentechmedia.com/articles/read/report-u.s.-energy-efficiency-is-a-bigger-industry-than-energy-supply
This is a website from Greentech Media, and it provides information in articles about green technology. In an article I read, it states that energy efficiency has a greater impact on the economy than energy supply. It gives information based on studies and facts proven. It's goal is to inform people about green technology.