Much of what would be considered cutting edge technology in the energy and AEC industries today can trace its roots back to past research efforts at the Pacific Northwest National Laboratory (PNNL), one of 17 US Department of Energy labs. Take solid-state lighting, for example—the lighting class that includes LEDs. PNNL didn’t invent LEDs, but has been instrumental in accelerating improvements to the technology and encouraging its penetration into the marketplace. Few other technologies in recent years have done as much to reduce energy use in as short a time. Once full market saturation is achieved, DOE estimates that solid-state lighting (SSL) has the potential to reduce total domestic energy use for lighting by half.
Detroit, a city that is still recovering from municipal bankruptcy, is a prime example of the potential of LEDs to cut into energy budgets. When the motor city filed for bankruptcy in 2013, about half of its 88,000 streetlights were not in working order, leaving much of the city dark at night and susceptible to vandalism and a host of other social ills. The city nearly chose to replace its lighting stock with high pressure sodium lights until theMunicipal Solid State Lighting Consortium, a technical advisory group backed by PNNL research, made an alternative suggestion. With PNNL’s help, the city is now in the process of replacing 65,000 streetlights with high-efficiency LEDs—an effort that will save an estimated $2.94 million annually in electricity costs and 45.6 million kilowatt-hours in energy, not to mention removing the equivalent of more than 40,000 tons of carbon dioxide from the atmosphere. And, since the replacement project began, Detroit’s crime rate has dropped 18%.
“Due in part to Detroit’s success, we are seeing LED streetlights flood the market,” says Dennis Stiles, program manager for building energy efficiency research at PNNL, pointing out that both Walmart and MGM Resorts International have pledged to replace their parking lot lights with LEDs. PNNL has helped develop many of the metrics used by the lighting industry to test and measure the performance of LEDs, a critical step in getting the technology from the drawing board to the manufacturing stage. They’ve also carried out field trials to see how well the technology fares in different applications. “We did installs in Minneapolis to see how things worked in the cold, and some in Arizona to see how it works in the heat,” Stiles says.
Leading LED Technology to Market
Technical analyses are just the tip of the iceberg of what PNNL is working on in the SSL space. “Early on, the focus was on replacement,” Stiles says. “You take out a 60-watt incandescent bulb and replace it with an LED lamp. But now, because of the way these products can be made, and the way you can design light products using these LEDs, you can rethink the way lighting is done. It’s no longer just a replacement option, it’s a completely new way of thinking about delivering light.”
LEDs are more efficient and longer lasting than other lights, but there is another important, and often overlooked, facet of the technology: they are highly controllable. They originate from microchip technology, Stiles says, and are built on a circuit board, meaning that many other functions can be embedded into LED light fixtures. That fundamental difference allows them to fit snugly into PNNL’s vision for buildings of the future—a new paradigm where every feature related to a building’s energy use, occupant comfort, security, and IT capability are knit together into a single, programmable system. “Imagine your lighting being connected and controlled as part of your larger building efficiency strategy,” Stiles says. “By connecting LEDs to more than just a power source, they can sense things like the temperature of a room, whether there is someone in the room, or whether there are 10 people in the room.”
LEDs also lend themselves to radically different design considerations that will be of interest to architects. Because theyproduce much less heat, they can be embedded in almost any design element, making the idea of light fixtures as distinct objects unto their own irrelevant. Rather than a ceiling with lighting fixtures hanging from it, the ceiling panels themselves could glow bright or dim themselves in response to the available daylight, user needs, and other parameters. They could change the mix of wavelengths that make up white light and their intensity to better suit the different uses that may occur in a single space at different times, for example. “You can have an architectural feature that is cool and glitzy and does many things, but also happens to put out high-quality light that better meets user needs and is extremely energy efficient,” Stiles says. “That’s where lighting is headed.”
To get there, LED lights need specialized sensors that are fully integrated with building control systems. PNNL is working on that, too.
VOLTTRON: Beaming Energy Information throughout the Grid
Although it may sound like a character from Star Trek, VOLTTRON is actually a software platform for the “smart” buildings of the future. VOLTTRON, which is now available with open-source licensing through PNNL, monitors energy use in individual buildings and manages which loads (i.e., energy draws—whether for lighting, heating, cooling, computing, or other needs) receive power at what time, all in a response to a signal from the grid. “The goal is to always balance loads behind the meter with generation,” says Srinivas Katipamula, a staff scientist in PNNL’s energy and environment directorate. “The purpose of VOLTTRON is to fully automate the process of demand response.”
Balancing energy use with energy supply has always been a goal of utility providers, but it has significant implications in terms of energy conservation and renewable energy generation. During peak load periods—say, when people get home from work, activate their heating or cooling system, start dinner, and flip on the TV—energy companies struggle to keep up with supply, especially if it’s a particularly hot or cold day. They charge the consumer higher rates during these periods and are more likely to switch over to their “less clean” energy resources to meet the spike in demand, says Katipamula.
But even more importantly, if the energy supply originates from a renewable source like wind or solar—what grid operators refer to as non-dispatchable resources—it is even more difficult to match production with consumption. Energy use may peak at 6 p.m., but the sun’s energy peaks at noon, and winds have a mind of their own. We might love the idea of these renewable energy sources, but there are severe limitations to implementing them on a mass scale given current grid infrastructure. That’s where VOLTTRON comes in.
“You get what you get, and they are highly variable,” says Katipamula of non-dispatchable resources. “In some areas of the country, wind and solar are nearing 25% penetration in the energy market, which is creating some reliability issues on the grid.”
When VOLTTRON senses a flood of cheap energy available on the grid (during periods of low demand), it switches on loads that can make use of it, even though occupants are not actively using the related appliance. And vice-versa—when there is a high demand on local distribution lines, VOLTTRON switches off any load that is not critical at that particular time. It has the ability to schedule energy use throughout a campus or neighborhood, or even at a city scale, according to user priorities and energy availability, making it a crucial tool for integrating distributed generation systems with the centralized grid.
Hot water heaters provide an easy example for how VOLTTRON works. There is no need to continuously heat a hot water tank unless hot water is continuously in use, which occurs only in spurts each day. However, says Katipamula, if there is surplus energy available, why not heat the water and use its thermal mass properties like a battery, storing the energy when it’s not needed for a time when it is? The same principle applies to the massive chilled water systems that are used to cool large buildings. “Buildings consume 75% of the electrical supply in the country,” Katipamula says. “So they have to be active participants in managing the energy on the grid.”
So what’s the connection with LEDs? Well, VOLTTRON is not just a grid-to-building communication platform, it is designed to host complete building automation systems, including sensors for fault detection and diagnostics. Since LEDs are like tiny computers masquerading as light fixtures, they communicate easily with the VOLTTRON platform, streamlining the integration of lighting with building controls. “In our current paradigm, we tend to think of lighting control systems as being separate from other building control systems,” Stiles says. “But LEDs are highly tunable. As the grid pulls on more and more renewables, we need to manage the dynamic profile of generation with more dynamic loads—solid state lighting can be a part of that.”
PNNL’s Long History of Building the Future
Despite the stereotypes, scientists are very much interested in the everyday practical ramifications of their research. Being an unbiased empiricist is important for maintaining the integrity of the scientific method, but every scientist is also a human being who cares about discoveries that will make the world a better place (or so we hope). They can also be downright funny.
Steve Shankle, director of the electricity, infrastructure, and buildings division at PNNL, has dedicated his career to making buildings smarter, more efficient, and more environmentally friendly. When asked about the lab where he works—a place that few non-scientists have ever heard of—he cracks open a bottle of humor: “We work on really important things. You know that special coating on M&M’s that makes them melt in your mouth, not in your hand?” Well, the technology that keeps M&M’s from being messy to eat is one of many from the annals at PNNL.
Like other more serious and impactful inventions, like optical digital recording technology and airport security scanners, PNNL has set its sights on much grander visions for buildings of the future: making net zero buildings a reality in the coming decades. Not just for the slim number of buildings that might have a LEED Platinum or Living Building Challenge label, but for the entire sum of the country’s building stock.
Actually, explains Shankle, the chemistry of candy coatings was a past project of the Battelle Memorial Institute, the world’s largest non-profit research and development organization, who operates PNNL and a plays a role in a handful of other government labs. At PNNL, the mission is to lay the scientific groundwork for industry innovation, with a focus on security, energy, and the environment—all of which are important to the AEC industry. PNNL scientists look at things on a generational scale and focus on the work that needs to be done now in order to remake the world as a healthier, safer, more sustainable place in 10, 25, 50, or even 100 years.
The Department of Energy has a broad goal of reducing the energy use in the nation’s building stock by 50% as the next generation of structures are built. In the near term, more than half of the states have ramped up their mandate for renewable energy—most are shooting for wind and solar to comprise 15 to 30% of energy supply by 2020, says Shankle. It’s not just a matter of installing PV panels and building wind farms; fundamental changes are required in the grid that distributes their energy and buildings that consume it, placing a tremendous demand on the private sector to realize the potential of these new energy sources. “In regions like Washington State and Texas, up to 50% or more of total installed capacity coming on is wind,” he says.
“Our research leads to new tools and algorithms that can be implemented by industry vendors,” says Shankle, who shepherds the work of 220 scientists and researchers toward that goal every day at PNNL. “We do the intellectual property development and then it gets licensed out to companies like Siemens or Alstom Grid, for example, who incorporate it into their products. That’s how the technology gets into the marketplace.”
Change Where it is Needed Most
“There are a number of trends that are roiling the electricity industry right now,” Shankle says. “There are a lot of technological challenges. We need control systems that are friendly and usable at the building occupant level. We need a smart grid; we need that to be real. But the basic theoretical understanding of how to do that doesn’t even exist. So we are working on advanced control theory to help operators figure out how to manage all of these changes.”
One of the low-hanging fruit has been to use VOLTTRON to deploy fault detection and diagnostics in building control systems, an area where PNNL estimates that 20% or more of energy use in commercial buildings could be cut. “For example, if a system has been left on after 7 p.m.and the building is unoccupied, VOLTTRON can actually turn off that system automatically,” Katipamula says. “Or to provide actionable information to the building operator, so that when the operator comes in, the operator can attend to the error.”
But because only the largest commercial buildings (more than 100,000 square feet) typically have building control systems, PNNL is working on ways to reach the rest of the building stock with similar precision controls. Building automation in small- and medium-sized buildings, which comprise 70 to 80% of commercial building stock, often consists of “little more than a thermostat,” says Katipamula, “but they also have significant scheduling problems.” PNNL is working with companies like Emerson Climate Technologies and Transformative Wave, who specialize in operating small and medium commercial buildings, to implement VOLTTRON in that context.
“VOLTTRON can actually be used as the building controller for smaller buildings that don’t have any building automation,” says Katipamula. In particular, PNNL is targeting rooftop AC units, where a tiny VOLTTRON “node” can literally be mounted on the side of AC housing. “You can literally do that for 50 bucks, and now your rooftop unit is communicating with the grid,” Katipamula says. “Previously, we didn’t have the ability to do that.”
The beauty of VOLTTRON is that each node communicates with the others across a given geographic region, allowing for a cost-effective strategy to disseminate the technology on a large scale. There is no infrastructure overhaul required, so the rollout of the technology could be quite swift. After small- and medium-sized commercial buildings, PNNL has its sights set on the residential market, meaning an interconnected network of building control nodes may soon translate the idea of smart buildings to the reality of smart cities.
Looking to the Cities of the Future
Nora Wang, senior engineer and associate program manager for building efficiency at PNNL, has spent the last year working to define a vision for how the built environment will change over the course of the next century. Together with industry leaders from more than 60 organizations, she convened a dozen panel discussions, each focused on a different aspect of buildings of the future, such as climate change, resilience, energy, health, and sustainability. Wang recently sat down to discuss her findings with gb&d.
gb&d:What sparked the idea of producing a century-long vision for buildings and energy infrastructure?
Wang:The reason, quite simply, for this exercise is the goals that have been set within the industry. We have a goal of net zero by 2030; other organizations have set a goal of carbon neutral by 2050. 2050 sounds far away; but if you think about building stock turnaround, it’s not a long period of time. The average service life of most buildings is 70 to 80 years. We are painting a picture of what buildings could be like in 100 years to figure out the process of how to get there.
gb&d:What are the most important aspects of that picture in your mind?
Wang: Scalability is important. We need to look at this in terms of mainstream buildings, not just the most advanced buildings. It’s also important not to fragment the different aspects of the building industry. Energy, water, construction techniques, economics, health, safety, regulations—all of those things have to be brought forward together.
gb&d:What role do you see for technology in the buildings of the future?
Wang: In the future, buildings will all be connected, so they can transact their utility services, or even ecological functions. Things like water purification, energy production, energy storage, and waste heat recovery can all be shared among buildings in a community. Microgrids will produce energy in one place and store it in buildings throughout the community. Some buildings will function as batteries and may receive income for providing that service. Technology will be needed to provide the structure to enable those transactions between buildings.
gb&d:What do you mean when you say a building can function as a battery?
Wang: There are many ways to store energy in different forms. The idea of a passive house is one way, storing heat in the walls and the floors. There is also technology to use ice to store energy, converting back and forth from thermal to electrical energy as it freezes or melts. But actual batteries may have a role to play, as well. We can look at electric cars as back-up energy sources for buildings, for example. During a catastrophic event or under an extreme weather condition when power is insufficient, buildings with less critical functions such as shopping malls or cinemas can become the energy sources for critical functions, such as hospitals.
gb&d:Considering electric cars as part of a community’s energy infrastructure does indeed sound futuristic!
Wang: It also connects buildings to transportation networks. That is part of our vision, as well, thanks to the push for autonomous vehicles and service-on-demand transportation systems, like we are seeing with Uber. There are implications for buildings: land use for parking, driveways, and even roads will be significantly reduced, opening up land for green space, pedestrians, and the ecological benefits that it provides.
gb&d:That sounds incredible. What other unexpected technological twists should we expect in the buildings of the future?
Wang:Well, wearable devices could be used to help us better understand occupants and make buildings smarter.
gb&d: Wearable devices? You mean things like smart watches and Google Glass?
Wang: Exactly. The future technology will go even beyond that. We are on the verge of being able to monitor our physiological data, day and night, at a minimum cost, with technology so unobtrusive you will forget it is present. Image a skin patch as thin as a temporary tattoo. This will allow us to collect biometric data and user preference and feed them into building control systems. Rather than creating a presumed comfortable indoor temperature range for a large space, a building can provide a personalized environment that is free of discomfort for anyone and with less energy use.
gb&d: Sounds terrific. And what do you see as PNNL’s role in helping the industry to realize these ideas?
Wang: We focus on the interoperability of different devices, so there needs to be coordination between different manufacturers. The dilemma of developing flexible, modular building systems is that different brands of equipment, controls, and sensors often do not talk to each other, which makes it very hard to make buildings smarter. So we are developing open source platforms that everybody can use and rely on to develop their own technologies. These are evolving so fast that a future building may experience several generations of technologies. The best way to adapt to unpredictable change is to develop modular building systems that make upgrades easy to plug and play. That means in the future everybody will need to use the same open protocol.
gb&d: And how do all these technological advances circle back around to energy conservation and environmental issues?
A Look Inside Asset Score
The ins and outs of a new rating system for building energy efficiency from the U.S. Department of Energy and Pacific Northwest National Laboratory
In an effort to bump up the energy efficiency of the country’s entire building stock, rather than just the high-end new construction market—which has long been the focus of the green building industry—PNNL and the DOE have developed a new nationally standardized rating tool. With the click of the mouse, you can input basic information on the “assets” of any building—things like the building envelope (roof, walls, and windows), lighting, hot water, and HVAC systems. The tool will then run a sophisticated energy simulation for the building and generate a report (free of charge) with actionable information for building owners and operators.
The tool provides an Asset Score ranging from 1 to 10 based on the energy efficiency of the building, which can be used to rate and compare buildings in the same way the miles-per-gallon ratings are used to compare fuel efficiency in cars. The report includes total estimated building energy use, as well as suggestions for building upgrades that will have the greatest leverage in improving overall building efficiency. A potential energy efficiency score is provided, based on the reduction in energy use that would result from the identified upgrades.
The Asset Score can be used for new construction projects and existing buildings with commercial, institutional, and multi-family residential uses. The DOE provides a separate tool for single family homes called the Home Energy Score.