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Learn About Building Performance

Most buildings are just like us. We wake up in the morning and go to sleep at night, just like the lights inside a building. We sweat to remove heat when we are too hot—buildings remove heat through their HVAC systems. Our pupils adjust for lighting, just like shading on windows limit the amount of light coming in at different times of the day. And just as we require care to be our best as we age, as buildings age and their systems begin to slow down, there are things we can do to help keep them healthy and running smoothly.

Buildings account for 70% of electricity consumption and about 40% of total energy in the U.S., and facilities in the commercial and industrial sector account for 17% of publicly supplied water. Moreover, Americans on average spend about 90% of their time indoors. Therefore, our buildings must run at their very best, optimized to get the most out of what we put into them, stay comfortable and safe for occupants, and remain secure and resilient to security threats and utility interruptions.

PNNL building researchers are transforming the way that buildings and their systems are evaluated, operated, and integrated. Whether you aim to learn more about buildings, systems, energy or water, our cutting-edge research and applied knowledge are here to help.

What's the best way to evaluate building performance?

Building Evaluation

To improve building operations, we first need learn about the building. When was it built? For how many hours is it occupied and what is its primary use? What kind of fuels does it use? Does it get very hot or cold in the summer or winter? How does this impact energy and water utility use and trends?

After establishing a building's characteristics, diving deeper with a site assessment provides details on the building's systems and operations. Like a detective, investigating the building's equipment conditions and operations can reveal clues as to why something may have seemed unusual during background data collection. This is usually done in person; although new remote methods are available and beneficial in some applications.

Once data is collected and verified, building energy models can help establish the baseline performance to compare against energy-efficiency measures and determine the most cost-effective changes and projects to implement. Not all buildings are created equal, which is why energy and water evaluations are tailored to best meet each building's needs.

To learn more about PNNL's building performance evaluation capabilities, see methods, tools used for building evaluations, or contact .

What is a Net Zero Energy building?

Net Zero Energy

Net zero buildings produce as much energy as they consume over a year. To achieve this, buildings need to first conserve as much as possible, improve their efficiency to the fullest possible extent, and generate energy from renewable sources to offset the remaining energy that they consume. Net zero buildings can still draw from the electric grid if renewable sources are not present to support the demand of the building, and then supply energy back to the grid when its renewable sources are generating more than is needed. Therefore, energy from the grid that was "borrowed" is returned to the grid later, resulting in a net energy use of zero.

In addition to the cost savings and environmental benefits, a net zero building also becomes more resilient to external influences, such as extreme weather events or utility interruptions. Designing and implementing projects to make net zero energy buildings can be key in securing critical assets against unforeseen events.

Some sites and buildings are better net zero candidates than others. Generally, the building should run on electricity, and be open to switching other existing fuels to electric to leverage electricity-generating renewables and minimize or eliminate other fuels brought into the building. Additionally, sites should have reliable renewable sources nearby. This can come in many forms. Is there dependable sunlight throughout most of the year? Are there prevailing winds in the area? Is real estate available for wind turbines or solar panels? Can the motion of water in any rivers, waves, or tides be used? How are the energy prices and rate options? (The higher the existing cost of energy at the site, the more valuable net zero can be.)

A successful net zero project also requires diverse expertise in building sciences, renewable resource analysis, energy efficiency, engineering, economics, and policy. Screening sites, conducting assessments, identifying opportunities for improvements, and consideration of alternative resource feasibility are all important steps to determine which buildings are viable candidates in achieving next-generation energy goals.

Net zero sites or facilities can be a key way to increase site resilience to energy and water utility disruptions. To learn more about working with PNNL on net zero buildings, visit site resilience or contact .

What is a Net Zero Water building?

Net Zero Water

A net zero water building is designed to minimize total water consumption, maximize alternative water sources, and minimize wastewater discharge from the building and return water to the original water source.

Achieving net zero water starts with identifying buildings where it may be economically feasible to tap into alternative sources, such as onsite storm water, graywater, or rainwater. We also need to understand the building's water usage by analyzing utility bills, equipment inventories and operations, and other site information. This establishes a "water balance," a record of where your water comes from, where it is used, and where it might be wasted. This can shape water conservation and efficiency efforts, identify leaks and wasted water, and also determine what measures might be beneficial. A site walk-through can further verify equipment and water use patterns and confirm the water balance. This is also an opportunity to confirm alternative water sources nearby that can offset the amount of utility-supplied water.

Together, this information combined with feasibility and economic analyses will help determine the plan for achieving net zero water in the building while also contributing to site independence and resiliency.

To learn more about net zero water, including details on measuring net zero water, building examples, innovative technologies, and design elements, visit the Federal Energy Management Program.

Net zero sites or facilities can be a key way to increase site resilience to energy and water utility disruptions. To learn more about working with PNNL on net zero buildings, go to site resilience or contact .

What are some ways buildings can become more energy efficient through their operations?

Building Data Analysis and Re-Tuning™

Building Data Analysis and Re-Tuning™

Our world is always changing, and so is the way we control and monitor building energy use. Large commercial buildings use sophisticated energy data management systems and building control systems (BCS) to manage heating, ventilating, and air conditioning systems and components. While sub-metering can tell a building owner when, where, and how energy is being used, many buildings are not properly commissioned, operated, or maintained, leading to inefficiencies, reduced equipment lifetime, and higher energy costs. Fortunately, building re-tuning can detect opportunities for energy savings and operational improvements.

Re-tuning begins with an experienced analyst leveraging data collected by energy data management systems and BCS to identify operational problems. Common problems include equipment operating when the building is unoccupied and equipment setpoints being fixed instead of dynamic. Once these problems are identified, corrective actions can be taken, such as optimizing equipment schedules to only operate when the building is occupied or programming equipment setpoints to automatically adjust based on the weather and temperature outside.

Our team has re-tuned over 25 million square feet of federal facilities and we continue to advance the re-tuning method. Our work on Enterprise Building Control Systems is revolutionizing re-tuning for buildings in an enterprise from a remote location. In addition, to reach a larger audience more quickly, we created an interactive learning course for improving a building's energy performance and the comfort and productivity of the building's occupants. The course provides a hands-on experience in data collection and analysis, walking down a building, and interactive re-tuning scenarios.

To work with PNNL and learn more about Building Data Analysis and Re-Tuning™ opportunities, visit the Building Re-tuning™ website or contact .

What are some ways buildings can become more water efficient?

Water-Efficient Technology

A building's most common water usage occurs in plumbing fixtures (sinks, toilets, showers, and drinking fountains), cooling towers, heating and cooling systems, and landscape irrigation. While common measures like high-efficiency plumbing retrofits and water reclamation efforts can substantially reduce a building's water use, the following less familiar and underutilized water-efficient technologies can help deliver even greater savings:

  • Acoustic leak-detection noise loggers identify and localize leaks in piping, allowing for timely repairs of leaks that may have otherwise gone unnoticed.
  • Connectionless food steamers operate without a boiler or drain connection, and save around 95% of water use compared to traditional boiler-based steamers.
  • Multi-stream rotational sprinkler heads apply water in rotating trajectories (see image above) and offer greater uniformity in irrigation distribution compared to traditional pop-up nozzles.
  • Onsite wastewater treatment systems provide a consistent source of alternative water for a facility.
  • Rainwater harvesting systems capture, divert, and store rainwater from rooftops for later use.
  • Sprinkler automatic shut-off devices feature an internal valve that automatically closes when the sprinkler head breaks, eliminating water loss through broken heads
  • Steam sterilizer condensate retrofit kits offer hospitals, clinics and laboratories an opportunity to substantially reduce the water use of steam sterilizers.

To learn more about working with PNNL on building and site water efficiency, contact .

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