Serious Energy has bought Agilewaves, marking the San Francisco-based startup’s second purchase of software meant to pull energy intelligence out of buildings and deliver efficiency.  The deal will bring Serious a whole new level of granular building energy data from Agilewaves’ detailed, if expensive, building monitoring system -- and it may bring Serious some new customers, as well.   

Terms of the deal announced Wednesday weren’t disclosed. Agilewaves was founded in 2006 with private and angel funding, and while it has been looking for funding since 2008, it hasn’t announced any investments since then. While it’s hard to say why these efforts haven't been successful, it could be because Agilewaves’ solution, which involves monitoring building power use down to the circuit level and detailing it via the web, is quite expensive to install, in the thousands of dollars per building range.

But Serious, which has raised more than $140 million in VC investment to pursue a shifting building energy strategy, could use that kind of detailed data. Its just-launched Serious Capital program offers building owners no-cost efficiency retrofits, based on Serious’ ability to finance the projects and pay itself back through energy reductions. That puts a lot of pressure on Serious to make sure it’s getting as complete and detailed a view of building energy use and waste as possible -- which Agilewaves’ circuit-level monitoring could well provide.

Serious plans to integrate Agilewaves’ Building Optimization System (BOS) with its own software-as-a-service energy efficiency platform, which is built on the software it got when it bought Valence Energy last year. As part of that process, “All of Agilewaves customers will eventually be migrated to a comprehensive consolidated platform,” Serious said in its Wednesday release.

So, who are Agilewaves’ customers? Agilewaves CFO Ed Campaniello told us last year that the startup was working with “upwards of 30 customers right now, including some of the leading real estate companies in the country,” though he didn’t name names.

Since 2009, Agilewaves has also been working with the U.S. Department of Housing and Urban Development on a project aimed at getting a more accurate energy efficiency view of public housing buildings in Baltimore. The “HUD Mark to Market and Green Initiative,” as it’s called, was aimed at getting an accurate view of just what financial benefits can accrue from the workaday window, fluorescent lighting and insulation replacements that make up the bulk of the federally supported energy retrofit projects out there.

As The New York Times reported this week, new studies are starting to prove out the benefits of these kinds of energy retrofits. But getting real-world data out of buildings will be key to verifying that the initial investment in efficiency can pay off at a predictable rate over time. Agilewaves’ work with HUD could lend it expertise in this kind of analysis.

Agilewaves has also built a system to track building performance specifically to meet reporting requirements for LEED advanced energy metering credits, to give another example of how technology is being married to building efficiency policy and practice.

The fact that Agilewaves actually installs sensors in buildings could also help Serious in the task of “continuous commissioning,” or maintaining the efficiency gains of retrofits over time. If not watched, buildings tend to see their efficiency gains slip over time as fans and compressors fail, sensors get out of whack, occupants reset or override thermostat and lighting presets, and other such daily wear and tear occurs.

While it’s cheaper just to design software that takes advantage of existing building systems to improve efficiency, getting it to work smoothly with those buildings may take some more on-the-ground expertise. Witness software startup Scientific Conservation’s decision to buy energy services company Servidyne and rebrand itself as SCIenergy earlier this year.

Serious Energy has already made a shift from a pure-play green building materials company to a software-based building energy management company. Its Serious Capital launch could be seen as positioning it in competition with giant energy services companies like Siemens, Schneider Electric, Honeywell and Johnson Controls. Getting ahold of the kind of submetering, circuit-level monitoring that Agilewaves offers may well be an expensive, but necessary, step toward making that competition possible.