They will originate from power plants either already in use or in the process of being constructed.
According to the IEA, there is little chance of achieving the ambitious goal set during the United Nations Climate Change Conference in December 2010 to limit the global increase in temperature to 2° Celsius (3.6° Fahrenheit) or less over the next ten years. In order to meet that goal, the percent increase in emissions from now until 2020 must be less than the percent increase that occurred between 2009 and 2010. BUT… Because the increase in emissions was directly linked to the global economy’s emergence from recession, a double dip would send emissions back down.
United Nations Environment Programme, (2010) "UN Climate Change Conference in Cancun delivers balanced package of decisions, restores faith in multilateral process", [online], Available: http://www.unep.org/Documents.Multilingual/Default.asp?DocumentID=653&ArticleID=6866