The United States’ 114 million households and more than 4.7 million commercial buildings currently account for nearly 40 percent of total U.S. energy use, according to the U.S. Department of Energy (DOE). In addition, buildings account for 39 percent of U.S. carbon emissions and consume 73 percent of the electricity generation and 55 percent of the natural gas. These numbers demonstrate the potential of alternative-energy and energy-efficient technologies, such as photovoltaic electricity generation, daylighting, solar water heating and geothermal space conditioning.
As the drive to reduce energy consumption, costs and carbon emissions continues to move forward, there is a wide range of technologies available to help building owners meet their energy goals and mandated energy limits. But where does one begin?
The changing role of technology
Forty years ago, building control systems for heating, ventilation and air conditioning were primarily pneumatic. Many mechanical and electrical systems interfaced pneumatically to electrical transducers and were typically minimal in scope due to the high cost. At the same time, building automation system suppliers were able to provide mini computer-based systems that enabled centralized scheduling and alarm notification for many of the building’s functions, according to Bob Dixon, vice president of industry affairs at Siemens Industry Inc., Building Technologies Division, Buffalo Grove, Ill.
“Eventually, with the advancement of direct digital control, the pneumatic systems were replaced with a more integrated digital approach to sensing and controlling building systems,” Dixon said.
Traditionally, the role of technology in buildings has been to make building components more energy-efficient, according to Patrick Hughes, director, building technologies research and integration center, Oak Ridge National Laboratory (ORNL), Oak Ridge, Tenn.
“More recently, technology has also focused on better integration, enabling buildings to continuously operate as efficiently as their energy-consuming systems allow,” Hughes said.
For decades, the attempt to make buildings more energy-efficient has been focused on developing more efficient equipment.
“Now, however, the technology is migrating from equipment design and manufacture to building performance and determining whether the equipment is operating within guidelines and tolerances and how equipment operations can be improved if they’re not,” said Andres Szmulewicz, consultant, Smart Buildings LLC, Spicewood, Texas.
As technology evolved, advancements in sensing, control and connectivity have provided building owners and managers with the ability to integrate and optimize energy supply, energy consumption and operating strategies in an environmentally friendly way that maximizes the lifecycle value of their facilities.
“The ability to integrate individual building components enables building owners to achieve higher energy savings than is possible with those components operating on a standalone basis,” said Ed Vineyard, group leader, building equipment research, ORNL.
Today, building technologies help enable cost-effective data and near real-time analytics to facilitate informed decision-making.
“These same technologies also form the backbone for the continuous commissioning of buildings, enabling them to perform at the highest possible level with their existing infrastructure and to not degrade over time,” Dixon said.
Unfortunately, there is no silver-bullet technology that allows buildings to perform at their highest level.
“However, there is a wide range of ‘silver buckshot’ technologies that have facilitated the march toward optimized building performance,” Dixon said.
For example, variable-speed technology allows today’s equipment to achieve energy savings through better part-load performance. There are equipment control systems that operate based on occupancy, such as smart, Internet-protocol-enabled, programmable thermostats. Controls that are evolving to be more learning-based and model-predictive gain an understanding of energy-use patterns; historical information predicts future use and provides optimal control. Advanced platforms that integrate disparate systems can leverage the functionality of one system to improve the efficiency of others.
“For example, lighting and shading systems can be integrated into a single platform that enables a strategy for use to be developed,” Szmulewicz said.
Metering and energy management systems, in addition, provide actual energy use and inefficiencies data to help building owners identify strategies to deal with energy- consumption issues.
“While building operators and owners may know that efficiency is an issue, they often don’t know what the specific impact is to cost without this information,” he said.
However, one of the most important technologies involved in energy efficiency and building performance may be analytics.
“Analytics software constantly monitors energy-consuming building systems for anomalies and generates reports that allow facility managers to make corrective repairs or perform preventive maintenance,” Szmulewicz said.
While the role of data analytics and management is growing, the trend is toward using automatic and behind-the-scenes technology and reducing human involvement, Hughes said.
Dixon said there is a great range of technologies to improve building efficiency and performance.
“From smart glass to intelligent sensors, from new building materials to smart devices, from on-site generation to cloud-based analytics—individually, each of these technologies can incrementally improve building performance. But, when fully integrated, the gains can be astonishing,” he said.
Technology comes with challenges
One technological challenge in the United States concerns the existing building stock.
“It is a greater challenge to improve efficiency in retrofit applications than in new construction,” Hughes said.
Older buildings lack the information-gathering capabilities that would be needed to improve control and efficiencies whereas systems in new buildings can be designed to collect what is necessary from the outset.
“One possible way to overcome this challenge would be to merge low-cost wireless sensors with building systems that will then provide the necessary information to the existing control system,” he said.
The difficulty for contractors is that successful wireless-sensor installations means considering factors traditionally unfamiliar to them, such as how the building’s construction materials and lines of sight between sensors and receivers can affect data-transmission range.
Wireless technology may also present specific challenges to the contractor when dealing with the next generation of wireless occupancy, light, humidity and temperature sensors.
“Contractors will need to develop new skill sets to layout, install and verify a system with sensors that are properly positioned to transmit the necessary data back to the control system for building performance optimization,” said Teja Kuruganti, research and development staff member ORNL.
Contractors are also faced with the challenge of having to work with a variety of IP-enabled building components, such as phones, cameras and controls, as these devices are migrating to the communications network. According to Szmulewicz, the migration toward IP-enabled devices is actually facilitating the penetration of structured cabling into automation networks.
In addition, contractors must deal with increasing numbers of renewable-energy, energy management and metering deployments. These installations are creating gray lines that make it more difficult to determine which areas of responsibility fall to the contractor.
“By the time the contractor gets involved in the project, many decisions are already out of [its] hands. It’s more important than ever that the different disciplines on a project coordinate and collaborate with each other as early as possible,” Szmulewicz said.
Natalia Locke, a building information modeling (BIM) manager in the Sherman Oaks, Calif., office of Stantec, believes getting the contractor involved at the early stage of the project is helpful and benefits the whole team.
“The use of BIM in the early decision-making stage benefits both contractors and designers in the areas of quantity takeoffs, scheduling, real-time coordination and the production of better sets of documents,” she said.
Contractors’ evolving role
“Electrical contractors will have to move beyond installation services to also provide IT capabilities as new technologies will require them to configure, test and commission wireless technologies that sense and control building systems such as lighting, heating, air conditioning and ventilation,” Dixon said.
Although Hughes believes the contractor’s fundamental role of putting building systems together and making them work will remain the same, those systems are becoming more sophisticated with new generations of sensors and controls that the contractor must learn.
“Technology improvements are evolving quickly year to year, forcing contractors to deal with new technology faster and faster,” Hughes said.
If there was one course of action contractors need to take to adapt to this world of technology and buildings, it would be to find the right integration and manufacturing companies to partner with. For Hughes, that course of action would be to participate in workforce-development programs and stay ahead of technology instead of abreast of it.
“Industry training courses need to address technology before the products hit the market. Mistakes become more costly and have higher consequences when dealing with integrated systems,” Vineyard said.
Contractors’ training needs are also evolving with the development of new codes, as states and local governments try to improve energy efficiency though mandated standards.
“Contractors need to stay current not only on the technology driving the industry, but on new installation methods and codes and standards requirements as well,” said Omar Abdelaziz, research and development staff, ORNL.
Over time, no one knows what will happen as the industry learns to use the new technologies that come on the market. Distributed generation may become part of the norm. Or will buildings create their own nanogrid, become part of mini- and microgrids, connect to the smart grid or completely disconnect from the grid? Technology in buildings offers many opportunities for enterprising contractors.
“The ones that do stay ahead will have opportunities that their peers won’t have,” Hughes said.