World Energy Solutions Inc. closed lower for a fourth consecutive trading day. The Worcester company last week posted a quarterly loss of $1.7 million, or 14 cents per share, greater than its loss in the same quarter last year of $917,000, or 8 cents per share. Revenue, though, rose 10 percent from the year-earlier period to $7.9 million. The company recently changed its revenue-recognition policy, which defers revenue from certain deals. “This is clearly a transitional quarter for us,” CEO Philip V. Adams said.