Another key lesson from new construction is equally important with green renovations: Commissioning and retrocommissioning are critical to seeing savings. "Certainly commissioning is critical, whether for a small renovation or a capital project," says Strazdas. Western Michigan actually has an in-house commissioning staff member for renovation projects, and it's something Strazdas says he highly recommends. "If you're large enough to do this, do this. Count all the hours you chase problems post-renovation, and apply those to commissioning."
Carlos Santamaria, vice president of engineering services with Glenborough, points out that if part of the financial justification for a renovation includes a utility or government rebate or tax incentive, commissioning will most likely be required. And therefore, facility managers should get in the habit of including commissioning as a standard part of the renovation process.
Cooke says that his organization always does commissioning with renovation projects, but adds another piece of advice. "What we really try to do, and would suggest you do, too, is to recommission." Cooke explains that, through no fault of anyone running the building, systems can get out of whack. Recommissioning is a periodic reality check to make sure systems are optimized to run as efficiently as they can.
The only way to know for sure systems are running efficiently is to measure and verify. "A lot of people get hung up on estimating, but buildings are dynamic," says Santamaria. "So it's hard to predict energy use. Metering of real-time data is something that needs to occur more frequently."
One of the biggest problems skeptics have always had with the LEED for New Construction rating system is that it relies on an energy model to award points for energy efficiency, but there's no requirement (though there are voluntary credits for M&V) to follow through and verify assumptions made during the energy model. So one main difference between a renovation and new construction project is that if a renovation is part of a LEED-EBOM strategy, facility managers are required to record a real-world energy result in the form of an Energy Star score — and it must hit at least 69 (the requirement goes up to 75 with the soon-to-be-released LEEDv4) for any level of certification.
While Energy Star is a great way to determine a "big picture" view of how a building is doing, some facility managers may want to get to a more "granular level," as Santamaria puts it. And for them, building into a renovation project the capability to do real-time energy monitoring with a network of submeters is the best tack to take to measure success.
At Toyota, Cooke says 99 percent of the facilities are equipped with real-time monitoring — that is, the capability to monitor energy data in 15-minute increments, with one person responsible at each facility for keeping track. Cooke says the organization is also starting to implement alarm capabilities. An alarm is automatically triggered if a particular system hits a pre-set energy threshold. "This definitely helps gauge our post-renovation energy use," says Cooke. "But really this just ensures that we're not using energy we don't have to be using."
Still, it's important to keep in mind all the different factors that ultimately make a renovation successful. Not every project has a specific energy component or an easily calculable return on investment. "Success is a mix of the qualitative and quantitative," says Santamaria. "The factors include energy efficiency, tenant retention, operational efficiency, tenant comfort, and asset value." Indeed, as Strazdas says, the most important factor of all is how happy the customer is. "We always layer energy strategies onto aesthetics and usability," he says. "For renovations, we're really focused on what the customer wants."
How To Realize Actual Savings From Green Renovation Projects
Commissioning, Retrocommissioning Are Critical Elements Of Green Renovations
