Closed-ended energy investment company Riverstone on Thursday said it was pleased with its first quarter performance and said its investment pipeline for the group remained 'robust'.The group said it currently has "several" actionable exploration and production and midstream investments in various stages of review and negotiation. At the end of March the group's net asset value was $1,137m (December 31st: $1,139m), or $16.00 per share (December 31st: $16.04). Its market capitalisation was $1,060m (December 31st: $1,106m). During the three-month period it committed total capital of $225m and invested capital of $157m. To date, the committed capital totalled $375m, equal to 30.6% of the total capital raised, while capital invested to date was $158m, equal to 12.8% of that raised. Chairman Sir Robert Wilson, said: "The directors and I are pleased with our performance in the first quarter of the year, as demonstrated by new commitments totalling $225m to Rock Oil, Fieldwood and CIOC. "The investment pipeline for Riverstone remains robust with several possible new investments in various stages of review and negotiation."NR