Data center energy management firm Viridity Software this week raised $8 million in a second round of funding from Battery Ventures and North Bridge Venture Partners, bringing its total haul to date to $15 million.

More than just monitoring energy usage — a common enough capability these days — the Amesbury, Mass.-based startup develops software that helps data centers weighs their power consumption against their physical IT infrastructure. With this information in hand, IT shops can do a better job of pinpointing trouble spots like underutilized servers. In essence, Viridity provides a stepping stone for cost-cutting strategies like server virtualization and consolidation, as well as situating servers to maximize cooling efficiency.

The message is clearly resonating with some businesses. The company revealed that it had signed on some key customers including F5 Networks, Highbridge Capital and LexisNexis. It also helps that its EnergyCenter 1.1 release provides new levels of auto-detection that helps take the guesswork out of profiling a data center’s energy usage.

From the looks of it, giving data center operators a roadmap to lower cooling and energy costs is not a bad business to be in.