I’m at the Greentech Media Networked Grid conference in San Francisco this morning, where one of the big questions being posed is — where has the venture capital for smart grid startups gone? According to Greentech’s Eric Wesoff, smart grid landed only about $53 million in VC so far this year, or about 2 percent of the $3 billion going to the green sector in the first four months of 2011. (That tally doesn’t include the $135 million put into OSIsoft, which provides data management technology for utilities as well as for broader manufacturing clients). What’s the deal? One big issue is smart grid’s utility-scale timelines to market — while consumer electronics or servers turn over every few years, smart meters and grid communications and controls systems are supposed to last decades, which is longer than most venture firms’ horizons. Smart meter startups like Silver Spring Networks and Trilliant have already raised hundreds of millions of dollars, and the big influx of VC capital into home energy management startups has arguably led to an over-saturated market. Finally, let’s not forget that what smart grid lacked in first-quarter VC may have been more than made up by smart grid corporate acquisitions, with Johnson Controls, Alstom, IBM, ABB, Schneider Electric, General Electric and others buying up smart grid software, equipment and services firms at a rapid pace.