Producing new commercial buildings that use 80 percent less energy than today’s buildings is a new target in U.S. Department of Energy’s fight against global climate change. Berkeley Lab researchers are developing the technologies that will help make this possible. If such a building’s remaining energy consumption is supplied by clean, carbon-neutral renewable energy, it would be responsible for little or no greenhouse gas emissions. The research teams are performing field testing and demonstration work of new technologies on the campus of the University of California, Merced. The UC Merced campus has five buildings which have received LEED ratings for sustainable design-four gold and one silver. The campus has been designed to be a living laboratory, with sensors and instrumentation to support the development and demonstration of energy-efficient technologies and practices.
When buildings are designed so that their systems work together to maximize energy efficiency, they can use substantially less energy than they do on average today, even as they provide heating, ventilation, air conditioning and lighting, together with power at the electrical outlet. For this enhanced performance level to be achieved the building needs to be constructed according to specification-not always the case today.
Newly constructed buildings need to be commissioned-the process of having a team of engineers start up the various systems in the building, test them to make sure they are operating according to design specifications and make adjustments if they are not. Commissioning is originally a naval term applied to the process of making sure ships are seaworthy. Commissioning of both new and existing buildings could save billions of dollars in U.S. energy costs, according to Berkeley Lab research estimates.
Finally, buildings need to be operated by a facilities staff with training in the use of sensors and monitoring systems that provide them with accurate, real-time information about the energy performance and environmental conditions within the building. This approach to improving efficiency in buildings selectively applies systems engineering methods that have transformed other industries, including the aircraft and automobile industries.
A problem today is that “we don’t measure the energy use of buildings in real-time,” says Mary Ann Piette, the Deputy Head of EETD’s Building Technologies Department. “Most energy management systems in buildings are geared toward controlling energy use, but without much feedback about how buildings are actually using energy.
A benchmark is a data set of performance metrics for the operation of a building, its energy use and the conditions within the building. Comparison of the performance metrics in different buildings can help a facilities manager pinpoint where specific problems in a building lie-for example, perhaps the lighting is efficient, but air conditioning energy use during the summer months is higher than normal for a building of that type, leading to the deduction that a chiller plant is underperforming. Benchmarks for each energy-using system in the building provide managers with the target data they need to ensure that each of their systems is operating efficiently.
Another need is for a broad, deep data set about performance of many, preferably thousands, of buildings in real-time-in other words, a building informatics repository. This would not only help building managers do a better job, it would help building scientists develop better control strategies for managing building energy use.
