Year % of total electricity output 1990 1.86443127619598 1991 1.80603005074795 1992 2.37397768257785 1993 2.60851774815017 1994 3.05023206425868 1995 3.97358646306232 1996 3.54261003086662 1997 3.41498357132846 1998 3.06851943550384 1999 3.67524431490516 2000 3.1325863038499 2001 3.47145512837783 2002 3.94499638134088 2003 2.26888523956723 2004 3.27127342164936 2005 3.8227288816199 2006 4.2078083534559 2007 3.88541998997311 2008 4.47926045981151 2009 5.70119560956488 2010 6.91813578394599 2011 8.35253987277588 2012 9.30358646625215 2013 10.8234117756488 2014 10.7784149666259 2015 11.4045705432362