Green and Gorgeous: By Reducing Emissions Energy Secretary Steven Chu Says U.S. Can Achieve Net Savings of US$680 Billion by 2020

Energy Secretary Steven Chu wrote an op-ed in this behemoth World Economic Forum report.  

For the next few decades, energy efficiency is one of the lowest cost options for reducing US carbon emissions. Many studies have concluded that energy efficiency can save both energy and money. For example, a recent McKinsey report calculated the potential savings assuming a 7% discount rate, no price on carbon and using only “net present value positive” investments. It found the potential to reduce consumer demand by about 23% by 2020 and reduce GHG emissions by 1.1 gigatons each year — at a net savings of US$ 680 billion.

[JR:  McKinsey report is here:  "McKinsey must-read: U.S. can meet entire 2020 emissions target with efficiency and cogeneration while lowering the nation’s energy bill $700 billion!"]
Likewise, the National Academies found in 2009 that accelerated deployment of cost-effective technologies in buildings could reduce energy use by 25-30% in 2030. IHS CERA Report