We knew things were going badly in the renewable energy industry, but this week we got a grim view of just how ugly it looks out there.

Today, research group New Energy Finance said first-quarter investment in so-called clean energy fell 44 percent from the fourth quarter of last year, which in the immediate aftermath of the credit crisis wasn’t exactly stellar itself.

The $13.3 billion of investment in the most recent quarter was 53 percent below the same quarter of last year, the group said.

Things are particularly bad in the United States, where financing of new renewable energy projects was only $500 million in the first quarter compared with $2 billion in the fourth quarter of last year and $5 billion in the first quarter of 2008, according to New Energy Finance.

That report came a day after several other groups, including Deloitte and the Cleantech Group, gave their own views of first-quarter activity in clean tech. Though they had different authors, all the studies sent the same message: green investment is way down, and it’s unlikely to bounce back any time soon.