Greentech marked its best year ever in 2010, and part of that is thanks to the wealth of activity across sectors during the fourth quarter. Global investment in clean energy surged, and while wind power remained the biggest greentech area, solar power saw the fastest growth. The energy efficiency sector appears to have more room for smaller players to make their mark amidst a rapidly maturing market. Meanwhile, China’s stance as a growing greentech giant continued to complicate its relationship with the United States. Companies mentioned in this report include General Electric, Intel, ZigBee, iControl, People Power and EnerNOC. For a full list of companies, and to read the full report, sign up for a free trial.