Energy utilities are getting with the program when it comes to smart grids, and that’s translating into interest in a generation of startups innovating new ways to track how energy is distributed across large networks.

A startup that is also traded on the over-the-counter bulletin boards, Ambient Corp. (OTCBB: ABTG) works on smart grid tech with utilities on the east coast. That includes Duke Energy, which just inked a $10.7 million contract with the company to further develop the technology, according to VentureWire (subscription required).

The investment follows closely on two others into similar companies: eMeter just received $12.5 million, and last week, GridPoint, which also works with Duke, took on $15 million more. But there’s plenty of room in the market; as we wrote several years ago, the smart grid space may be worth as much as $45 billion.

Ambient, which is based in Boston, also picked up a $2.5 million investment in January.