Save Your Energy
- By Michael Fickes
- November 1st, 2012
An emerging process called monitoring-based commissioning (MBCx) may be able to cut energy use in your next new school building by up to 70 percent compared to your existing buildings.
It sounds incredible, but that is indeed what industry experts are saying. “Building automation system capabilities aren’t typically utilized fully, today,” says H. Jay Enck, co-founder and chief technical Officer with Duluth, Ga.-based Commissioning and Green Building Solutions, Inc. (CxGBS), a company that provides MBCx services.
“Integrating controls is important because it helps you start generating data to analyze,” continues Enck. “The more data you have, the more valuable the MBCx.
“Most of the buildings we monitor save an average of 30 percent, but at the high end, we’re seeing reductions of 60 to 70 percent,” he explains. “The savings depend on what you have to work with.”
A new building will, of course, have all of the latest energy saving lighting and heating, ventilating and air-conditioning (HVAC) systems. It will follow the latest building code specifications calling for well-insulted exterior envelopes. It will integrate precise digital building control systems that you can monitor and adjust using your computer’s browser whether you are in your office or at home.
Older buildings that have been upgraded may have some of this. But they probably won’t have the whole package.
With the whole package, you can wring astonishing savings from your building with MBCx.
What Is Monitoring-Based Commissioning?
Back in 2009, the Lawrence Berkeley National Laboratory in Berkeley, Calif., reported on a study of commissioning carried out on 24 buildings in the University of California and California State University systems.
The report was called “Monitoring-Based Commissioning: Benchmarking Analysis of 24 UC/CSU/IOU Projects.” You can get a copy of the report by Googling the title.
The project connected numerous sensors to each piece of equipment in each building. The sensors reported continuously on energy use by each component of building utility systems — water, electric and natural gas.
Data from the sensors recorded electricity use for lighting, air conditioning, water pumps and so on. More sensor data cataloged water and natural gas usage across the portfolio of buildings.
Everything that used energy in the buildings had a sensor reporting on that use.
Engineers analyzed the data looking for operational deficiencies. At the same time, they developed interventions to repair those deficiencies. According to the study, the engineers identified “1,120 deficiency-intervention combinations.”
Most of the deficiencies showed up in the HVAC equipment. Sixty-five percent of the sites developed HVAC problems that wasted energy. Next, 59 percent of the sites developed energy-wasting problems with air-handling and distribution systems. Twenty-nine percent of the sites had cooling plant problems. Heating plants at 24 percent of the sites wasted energy.
With MBCx, when the monitoring system discovers a deficiency, it reports to a person, and a maintenance technician can be dispatched to the site to set things right.
That’s the trick. Find problems as soon as they develop and fix them right away.
The results of the Lawrence Berkeley National Lab study are impressive. It cost $2.9 million to build out the MBCx system for the 24 schools. Over the next 30 months, the commissioning process saved $2.9 million and paid for the system. After payback, of course, it becomes possible to divert savings into other areas. Presumably, the 24 schools that participated in the study are continuing to benefit from savings.
MBCx for Pre-K-12
While MBCx is catching on in commercial buildings and has begun to emerge as a tool on college and university campuses, industry observers say it has not caught on in pre-K-12 schools.
Observers say that installing MBCx systems in older buildings with older equipment make it difficult to collect the appropriate data.
In addition, MBCx systems can be cost-prohibitive unless you do it yourself, a task that many pre-K-12 facilities departments aren’t equipped to carry out.
Finally, it takes a dedicated staff to operate the system efficiently once it is operational. The point here is that it isn’t worth doing unless you are willing and able to squeeze out the savings made possible by MBCx. And many pre-K-12 maintenance staffs are already too busy putting out fires.
Then again, you might consider the process when you build a new school. By asking for a design that will enable MBCx, you can start with a school that has no maintenance fires burning. The systems will work the way they are supposed to work right from the start. The maintenance job will be to keep them working that way with commissioning.
“Commissioning starts with integrating automated building control systems for lighting, water, HVAC and fire-life safety and security systems,” says Carlos Petty, vice president and group manager with the New York City-based Syska Hennessy Group, a consulting engineer that provides commissioning solutions.
Integration can be handled with an open communication system such as the Building Automation Control Networks (BACnet) or a proprietary system provided by companies such as Siemens and Johnson Controls, continues Petty.
This is indeed happening in new pre-K-12 school buildings today.
“Everything we do today has a full-blown control system,” observes Tim Lehman, mechanical discipline director with the Celina, Ohio-based architectural firm of Fanning Howey. “We’re monitoring incoming electricity, natural gas and water, and we’re enabling users to monitor consumption and to build historical databases to compare costs down the road.”
In other words, today’s new schools frequently have an infrastructure that may make installing MBCx affordable. Maintaining the school according to the commissioning systems dictates will pay back the cost of the system in a reasonable time and create savings that may be diverted to more educational purposes.
“Facility managers should take a snapshot of the building when every system is working properly,” advises Petty. “Then you send maintenance technicians out to check on operations once a month. Or you can buy equipment that will send data to a service to identify problems and provide direction for your maintenance technicians.”
Buildings with integrated and automated building control systems do use less energy. With a commissioning protocol, you can save even more. You can cut energy use further, while using less labor. “MBCx enables you to use labor more efficiently,” says Enck. “The commissioning system identifies problems, and you give your technicians the right information. They won’t have to spend time figuring out what is wrong. They will go to the job with the right parts and finish with time left over for other tasks.”
MBCx may be the way to make building automation systems finally deliver on the promise of energy efficiency. It’s something to keep an eye on.