5 ways buildings have reached a 'GREEN' tipping point
<p>What does 'green' really mean? This guide spells out, letter by letter, how the U.S. Green Building Council is pushing the definition.</p>
As the U.S. green building movement enters its third decade, the market has reached a tipping point.
The 2013 global Energy Efficiency Indicator [PDF] research study of 3,000 facility management executives indicates that only 5 percent had certified a green building before 2012. Yet 29 percent plan to certify a least one facility in 2013. This represents tremendous growth, but as the market evolves for green buildings, so should the definition of green buildings. LEED v4.0, the updated USGBC rating system, takes a big step forward in this evolution.
In the next decade, buildings will become more grid-responsive, resilient, efficient, energy-positive and networked. Put those terms together, in other words, and they spell "GREEN."
1. Grid responsive
One big change is that buildings will become more responsive to the grid. An early example of grid interaction includes demand response, where building owners agree to curtail non-critical building loads or turn on back-up energy sources during grid emergencies in return for compensation from utilities, grid operators or demand response aggregators. The 2013 EEI survey indicated that 14 percent of U.S. organizations currently participate in demand response programs. This capability, however, represents just the tip of the iceberg when it comes to the opportunity for buildings to provide valuable and profitable services to the electrical grid.
Through the use of automated demand response [PDF] and predictive controls, building energy consumption can be continuously adjusted to reduce demand at critical times of the day in response to hourly pricing signals from the grid. An early adopter of this strategy is Georgia Tech, where the campus-wide building management system downloads current and predicted future energy prices every hour over the Internet and adjusts temperature set points across the campus, reducing demand by up to 7 percent.
Other, more advanced capabilities include providing spinning reserve and grid regulation services. In these cases, building energy demand is required to respond to signals with either a 10-minute or four-second response. This is a perfect application for site-based electric battery storage.
Experiments at our Johnson Controls corporate headquarters facility demonstrated the capability to track a four-second test signal from the PJM grid operator with 97 percent accuracy using Li-ion batteries and a commercial building management system. When not providing grid regulation services, the batteries also can be used for demand limiting and PV solar firming.
Superstorm Sandy taught us that the design and operation of our buildings is critical to minimizing damage, maintaining operational integrity and providing critical services during and after extreme weather events. Following Hurricane Sandy, many grid-connected solar PV systems were not operational because of safety systems installed to protect utility workers and grid integrity. The availability of even a limited amount of solar energy or distributed generation, combined with energy storage and a secure grid disconnect mechanism, would allow buildings to provide critical services over extended periods of time.
One key recommendation in the August Hurricane Sandy Rebuilding strategy reinforces the important role that distributed energy systems and smart building controls can have in improving community resiliency. "The new approach would define policies and technical requirements for how to incorporate smart grid technology, microgrids, building controls and distributed generation, including CHP, with two-way flow networks into the grid. … This approach would allow building controls to provide a minimal level of service such as basic lights and refrigeration during emergencies," the strategy noted.
In the 2013 EEI survey, 51 percent of U.S. respondents said they had installed or plan to install distributed generation with reliable fuel sources to provide power for extended periods. Additionally, 39 percent said they installed or plan to install solar panels with a secure grid disconnect mechanism to use as an emergency back-up system.
Building efficiency has continued to improve over the years, resulting in significant energy and operational savings. Our EEI research indicates that lighting, HVAC and controls are the most popular energy efficiency improvement measures; more than two-thirds of organizations have made these improvements in the past year. An increasingly important area of attention is energy-focused behavioral and educational programs, where 44 percent said they had implemented improvements in the past year.
Organizations approach behavioral efficiency improvements in a number of ways. In the United States, green teams or champions have been employed at 36 percent of organizations, while social media tools have been used by 34 percent of organizations. Other approaches include creating sustainability games or challenges (22 percent) and installing green kiosks (21 percent). A new study from the Institute for Building Efficiency summarizes best practices in workplace sustainability engagement and includes an online tool to help organizations prioritize the best engagement tools and practices for their employees.
4. Energy positive
While energy efficiency always should be the first step in reducing the environmental footprint of buildings, there is growing interest in near zero, net zero and energy positive buildings. Hundreds of successful net-zero energy buildings are in the United States. The State of California has included net zero energy as a 2030 goal for commercial buildings in its energy efficiency strategic plan. Despite the technical and economic challenges of net zero energy, 46 percent of U.S. organizations responding to the 2013 EEI survey said they intend to achieve near zero, net zero or energy positive status for at least one facility in the future.
The U.S. Department of Defense is at the leading edge of net zero energy facilities. The U.S. Army has established a net zero initiative that includes achieving net zero energy, water and waste at a number of installations around the world. There are a number of advantages to considering energy positive goals at a campus or community level. One upside is improved economies of scale, with distributed energy and district cooling and heating plants designed to serve multiple facilities. Also, retrofitting existing large commercial buildings to net zero energy can be extremely expensive or impossible depending on the configuration.
The final area of innovation in GREEN buildings is networking. Smart building or smart grid technology was installed by 19 percent of U.S. EEI survey organizations last year. Smart building technology provides the data and information infrastructure needed to measure building conditions, monitor building performance, control building systems and manage energy and assets across a building, campus or enterprise. Smart building technology was rated the second most likely technology to increase in market adoption over the next 10 years.
The Empire State Building retrofit project is a good example of the benefits of implementing smart building technology. It's predicted that the retrofit project will result in energy savings of 38 percent. Of this, 20 percent is due to building management system improvements including building-wide implementation of digital controls, wireless sensing, demand-controlled ventilation, automated day-lighting and intelligent plug-load controls. A tenant energy portal also supports employee engagement and behavioral change programs.
The future of "GREEN" Buildings
Not only is green building technology moving forward, but green building rating systems are improving as well. LEED v4 includes a number of new credits and prerequisites that support these new industry trends and capabilities, including enhanced lighting and plug-load controls, building-level and advanced energy metering, measurement and verification, demand response and indoor air quality monitoring.
Johnson Controls will demonstrate the "Future of GREEN Buildings" Nov. 20 to 22 at the 2013 Greenbuild Expo in Philadelphia. Photo of the Bullitt Center, one of the greenest commercial buildings in the world, via Flickr