Social energy efficiency

Was watching Jimmy Carter on CNN. Wow...his speech on peace, development, palestine, corruption, development very interesting. He said that in his term (began 1977) oil usage was reduced in the US from 8million gallons to 4million (I don't know the time period) and now is back to 12million. Just interesting to see what can be done by introducing efficiencies,....apparently they encouraged people to install solar etc. A very inspiring leader.