U.S. venture capital investment in cleantech companies increased by 54% to $1.14 billion in the first quarter of this year (Q1'11), from $743.3 million in the first quarter of 2010 (Q1'10). This increase occurred despite a 13% decrease in deals year-on-year from 79 to 69, according to an Ernst & Young LLP analysis based on data from Dow Jones VentureSource. The top 10 deals in Q1'11 totaled $683.1 million, 60% of the total raised for the quarter, and two deals accounted for 18% of the total dollars raised. "The U.S. cleantech market experienced continuing momentum - both from a venture capital perspective and among the larger investment community," says Jay Spencer, Ernst & Young LLP's Americas cleantech director. "The second generation of solar companies and larger, later-stage rounds dominated VC investor interest in Q1." The energy/electricity generation segment, led by strong solar investments, raised $450.3 million through 16 deals in Q1'11. The solar sub-segment accounted for 32% of the total dollars raised for the quarter with $362.7 million, a 162% gain from Q1'10.