How much money did green technology startups raise in the first quarter, anyway? It appears that the answer to that question relies on how you define what makes a startup “green” in the first place. Today’s example comes from an Ernst & Young analysis based on data from Dow Jones VentureSource, which put the first quarter’s cleantech venture haul at $1.14 billion, up from $743.3 million in the same quarter last year. That figure is way smaller than the $2.57 billion in first quarter green VC reported by the Cleantech Group last month — what’s the difference? I’m guessing that Cleantech’s list included some companies that Dow Jones didn’t, based on a more tangential connection to definitions of green technology. For example, Cleantech Group named Plastic Logic as the top VC earner in its “materials” category, with a $200 million equity round raised as part of a larger funding package in the first quarter. But the California-based company’s connection to green technology is mainly based on the idea that its plastic electronics reader product could replace viewscreens that use more materials. Despite the differences in categorizing green tech, both the Ernst & Young and Cleantech Group reports did find that VC investment rose in the first quarter of this year, so the trends are moving in the right direction — even if larger-scale renewable energy investment fell in the first quarter.