May 9, 2019 / Zero Net Energy -- Every year, New Buildings Institute (NBI) digs into its extensive Getting to Zero Buildings Database and analyzes the information collected from thousands of low-energy projects across the United States and Canada in order to offer the market an official count of zero energy (ZE) buildings and related trends. ZE is defined as ultra-low energy projects that consume only as much power as can be generated onsite by clean, renewable resources. However, this definition is evolving to consider multiple buildings in a campus or neighborhood that use a larger, central solar array.
The official 2019 count is 580 certified, verified and emerging projects, according to the 2019 Getting to Zero Project List that NBI released today. That is a 10-fold increase since NBI started tracking buildings in 2012. Verified and certified buildings have provided energy use and power production data to NBI to validate their ZE status, or have been reviewed and approved by the International Living Future Institute’s zero energy certification or the U.S. Green Building Council’s LEED Zero program. Emerging buildings are those that have a stated goal of achieving zero energy, but do not yet have 12-months of energy use and production data to share or have not yet hit the zero energy performance target.
Growth in the count is confirmed by reported plans to invest in zero energy buildings over the next 10 years, according to Johnson Controls’ 2018 Energy Efficiency Indicator Study. Clay Nesler, Vice President of Global Sustainability and Industry Initiatives at Johnson Controls, presented the findings during a webinar today explaining that of their customers surveyed, “61% of U.S. respondents are very or extremely likely to have one or more facilities that are nearly zero, net zero, or positive energy or carbon status within the next 10 years.”
“That is an amazingly high number considering if we had asked this question only four years ago, we probably would have been in the single digits,” Nesler said. “Qualitatively if we look at our data over the past five years, the trend toward net zero energy and carbon buildings is advancing twice as fast as we saw with green building certification. It is in fact, the key trend driving investment,” he said.
In addition to growing private-sector investment, more and more states and cities are calling for zero energy and zero carbon building goals in their policymaking and for their own buildings. From Washington State to Virginia, governors are issuing executive orders and pursuing upgrades to energy codes. Legislatures are passing bills to require zero energy, and increasingly zero carbon, performance outcomes for both residential and commercial buildings. Cities likewise are using building energy policy as a lever to reduce carbon locally as buildings are responsible for up to 75% of carbon emitted in cities. Programs are being implemented that provide technical support and financial incentives that are spurring market adoption.
ZE’S MAGIC NUMBER: 22 EUI
Of the documented projects, the median gross site energy use intensity (EUI) is 22 kBtu per square foot per year. That means ZE-verified buildings on average use 60% less energy than other comparable existing U.S. commercial buildings and 46% less than new buildings under California’s Title 24.
“How low can they go?” asked Cathy Higgins, NBI Research Director when sharing the analysis. “It’s pretty amazing to me to see buildings operating at less than half the energy use of standard buildings and even 40% less energy than the most advanced building codes in the country [CA Title 24],” she said. The growing number of projects and technology application trends also show an increasing capability of the market to deliver on zero energy performance. Higgins reviewed the mainly “off-the-shelf, market-ready” technologies applied in the ZE building set including:
- Heat Pumps
- Ventilation: Natural, Dedicated Outdoor Air Systems (DOAS), Demand Control Ventilation (DCV)
- Highly Efficient Thermal Envelope
- Building Orientation & Glazing Ratio
- Solar Control – Shading
- Daylighting Access and Controls
- Energy Management Systems
- Building Dashboards
- Radiant Heating/Cooling & Chilled Beams
- Plug Load Reductions
- Energy Recovery Systems