How Small-Town America Cuts Energy Costs

Intelligent building technology lets even small cities on tight budgets save money while becoming more sustainable.

by / August 31, 2012

Is it smart for small cash-strapped cities to spend millions of dollars to upgrade government buildings? It could well be, if the buildings consequently grow smarter.

Used in conjunction with efficient heating, ventilation and air conditioning (HVAC) systems, plus new lighting and other energy-saving equipment, smart building technologies are helping some local governments cut energy consumption and reduce costs. Smaller cities and counties — even those with scarce resources — may realize these savings by cutting utility bills and better managing the maintenance of building equipment.

In Merced, Calif., for example, a series of facilities upgrades has helped the city save enough in less than a year to cover the first payment on a $7.16 million bond with money to spare. “We think we’re going to have about $30,000 worth of savings,” said City Manager John Bramble.

Although a mild winter might account for some of the reduced cost, there are other factors. “I attribute a big chunk of it to the controls that give you the energy savings in a large building,” said Dan Arnold, Merced’s public works manager. In Merced’s case, the controls reside in the Apogee Building Automation System from Siemens Building Technologies.

What Makes a Building Intelligent?

Smart building technology collects and analyzes data from multiple in-building systems in order to spot problems, optimize operations and schedule maintenance. Often, the technology acts automatically to adjust system activity. “Without any human intervention, the smarts in the building are continually monitoring the conditions and putting different systems at the optimal point to minimize energy use and maximize occupant comfort,” said Jim Dagley, vice president of channel marketing and strategy for North America Systems at Johnson Controls, based in Glendale, Wis.

The technology also might send alarms to building engineers. “The software tools can read the data points — the temperatures and flows and pressures and so forth — and determine whether or not the system is running optimally,” said Jim Sinopoli, managing principal at Smart Buildings, an engineering and consulting firm in Spicewood, Texas. If the software detects a malfunction, it can recommend a specific action and create a work order.

Photo: In Merced, Calif., Public Works Manager Dan Arnold (left) and City Manager John Bramble facilitated a series of building upgrades that saved money and jobs. Photo by Jessica Mulholland

The “smarts” that create a smart building might lie within a single building management platform, such as Siemens’ Apogee system or Johnson Controls’ Metasys Building Automation and Control System. Or software might integrate data from multiple building management systems, along with security systems, utility meters and other entities that generate data. Both Siemens and Johnson Controls offer the ability to integrate data from different systems — including systems from different vendors. Some third parties, such as IBM, also offer this capability.

“We look at all the data coming from all the systems holistically,” said Dave Bartlett, vice president of industry solutions for IBM’s smart buildings business. “Then we run analytics to get better insight into what’s happening at the moment and also do predictive analytics.”

Merced’s smart building project started in 2009, when the city formed a committee to identify improvements that could save energy and money in government facilities. In 2011, Merced awarded Siemens a contract for a package of upgrades and retrofits aimed at energy conservation. Among other activities, Siemens and its subcontractors replaced 34 rooftop HVAC packages, replaced more than 5,600 street lights and installed low-flow water fixtures in all of the city’s buildings.

While those upgrades were all smart moves, it’s the Apogee system that really makes Merced’s initiative a smart building project. Apogee collects data from the HVAC and lighting systems in several city facilities, including the City Hall. Displaying information about system operations in those buildings in real time on a digital dashboard, it allows building engineers to monitor performance and make adjustments, Arnold said. “You can drill down into the actual wall thermostat and adjust the settings from the computer.”

Engineers use the system to specify how to heat or cool individual rooms depending on the time of day, with variations for special events, Arnold said. The system also takes action automatically, based on established rules about performance.

For instance, when many people assemble in a room for a meeting, sensors might detect that the crowd is pushing the level of carbon dioxide in the air past the point of comfort. When that happens, Apogee sends a command to open a set of vents, drawing fresh air from outside.

Without those sensors, the vents would stay open throughout the meeting, even in summer when they would draw in hot air and overtax the air conditioners. With the sensors in place, the vents stay closed until carbon dioxide in the room reaches a critical level. “Then the ‘economizer’ will open, exhaust the building and then shut down,” Arnold said.  

Another element of Merced’s system uses motion-based and infrared sensors to determine whether a room — or even a single cubicle — is occupied or empty, and turn lights on or off accordingly. It also uses “light harvesting” to conserve energy in portions of City Hall where offices have windows.

As the sun starts to shine through those windows, sensors prompt nearby lighting fixtures to dim themselves, Arnold said. “There’s no need to have all this power consumption to light up a fixture next to a window.”

Card Readers and Light Fixtures

Along with sensors, other triggers might prompt a smart building system to adjust environmental controls to meet changing conditions. Consider, for example, a government employee who comes to the office on Saturday afternoon to do some extra work, said Sinopoli. To gain entrance, the employee swipes an access card through a reader linked to the security system.

Smart Parks

Merced’s plan to reduce costs and conserve environmental resources through the use of intelligent controls extend beyond the walls of its government buildings. As part of a recent $7.16 million energy conservation upgrade, Merced installed 35 irrigation controllers in seven city parks.

Drawing data from several weather stations in and near the city, the controllers automatically adjust the sprinkling times based on the current temperature, humidity and wind conditions, said Dan Arnold, Merced’s public works manager. “We can program [a controller] to the type of shrub or grass variety that’s there as well, and to whether the ground is sloped. If it’s raining, the sprinklers will shut off. If it’s super hot, the system will increase watering times a little.”

To prepare for the system, an engineer surveyed each spot where the city planned to locate a controller, evaluating soil, plants and other factors to determine specific watering needs, Arnold said. The controllers use that data to establish the basic sprinkling patterns.

Installing automated irrigation controllers was one of many suggestions that emerged from a 15-person committee that Merced convened in 2009 to identify opportunities to save energy in city operations. City Manager John Bramble suggested the controllers, hoping to avoid irrigating park sod while rain was falling. “It’s something that irritates citizens,” he said. “It irritates me.”

Today, with smarter sprinklers at work, Merced’s parks get exactly the level of watering they need — and only when they need it.

“That access card could be tied to lighting or cooling,” Sinopoli said. Since the smart building system knows where the individual works, it can give a command to light and cool his office while he’s at work there.

Besides matching system performance to the needs of occupants in real time, smart building technologies monitor the daily operation of HVAC and other systems, ensuring that they work as efficiently as possible. That doesn’t simply mean detecting malfunctions. It also means ensuring that systems are set in the appropriate mode for current conditions.

For example, a series of connected buildings might have numerous air handling units, said Bartlett. “Each one could be operating very efficiently. But one of the things we look for is whether they’re all performing to the same task.” Due to configuration errors, two units that maintain the environment in contiguous portions of the building might be working at cross purposes — one pumping cooled air as the other produces heat.

A smart building system might detect this anomaly and correct it, highlight the problem on a dashboard display, send an alert to the appropriate manager or automatically create a work order so engineers can resolve the problem.

Although energy savings is a primary benefit, smart building technologies also can reduce maintenance costs. For example, software that consolidates data from multiple systems in multiple buildings provides a unified view of all potential malfunctions. “You have one software tool that can deal with alarms across the city or county, rather than disparate alarms,” said Sinopoli.

If 10 problems trigger 10 alarms in one morning, engineers can get information about those problems from a single source, Sinopoli said. They gain a chance to prioritize those alarms, sending workers to deal with the most pressing ones first, or sending one worker to deal with several problems in one building at the same time.

The technology might also help engineers get to the root of a problem faster. “You may get 10 alarms from one building, but by doing some analytics, you find out it’s really one event,” Sinopoli said. “It may be one piece of equipment that’s failed that triggered five or six pieces of equipment down the pipeline.”

One final way in which smart building technology can save money for a city is by helping it shift some of its energy usage to periods of lower overall energy demand. Such adjustments can win a city lower rates through a utility company’s demand pricing program.

“You start to get smarter with your energy monitoring — knowing what you have, where it’s going, if it’s ramping up in a particular part of the day,” said Dennis Thompson, who is in charge of business development for Siemens Industry’s Northern California District. “The more knowledge you have, the more attractive you are to the utility providers, because you can become a predictable part of the grid. And you can make adjustments that they can depend on.”

If the utility has trouble generating enough power on a hot day, for example, it can turn to the customers who have signed up for its demand response program, Thompson said. Because those customers have committed to reducing their energy usage by a certain percentage at the utility’s request, they eliminate the need for widespread brownouts.

“If you can guarantee that you can drop, say, 20 percent of your load within 20 minutes of notification, they will guarantee that you will stay on the grid — you won’t brown out or go black — and, two, you’ll get a reduced rate,” Thompson said. Customers with smart building systems have at their fingertips the information they need to make that kind of commitment.

How to Pay?

Although smart building technology offers the chance to save a great deal of money while reducing a city’s carbon footprint, the necessary upgrades require a serious investment. How does a cash-strapped small-town government afford such a project?

One possible solution, offered by both Siemens and Johnson Controls, is a performance guarantee. “We’ll put together a package and say, ‘We can save $25,000 a year in energy in this old city hall if we put in some new systems,” said Dagley. “If the savings come back and they’re only $20,000, Johnson Controls will write a check for the difference.”

That’s the same kind of deal that Merced struck with Siemens. “If we didn’t save money, they would make up the difference between what it cost and what they anticipated they would be able to save us,” Bramble said.

A grant of $250,000 from the American Recovery and Reinvestment Act program helped Merced with some of the cost of the installation. The rest came from a 16-year bond issue worth $7.16 million.

Siemens started installing the new technology in spring 2011, and by May 2012 it had most of the system operating.

So far, Bramble said, the system has performed extremely well. “Staff has indicated that we have greater savings than we had originally anticipated.” After making its first bond payment, extra savings provided money to fund some new city initiatives, he said.

“It really has been a very positive project for us. Everything that we had hoped for in terms of improving the environment and saving money has come true.”

Merrill Douglas Contributing Writer