How many US and Canadian buildings have reached zero energy, and how did they do it?

by Brianna Crandall — May 27, 2019 — 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. “Zero-energy” is currently 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.

NBI bar graph of yearly count of zero-energy buildings

Graphic courtesy NBI

The official 2019 count is 580 certified, verified and emerging projects, according to the 2019 Getting to Zero Project List that NBI just released. That is a ten-fold increase since NBI started tracking buildings in 2012, points out the organization. “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 Building (ZEB) 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.

NBI map of zero-energy buildings

Graphic courtesy NBI

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 recent webinar 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.”

Nesler added:

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. 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.

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, notes NBI. 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.

Zero energy’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, according to NBI.

“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].”

Technologies supporting zero energy

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 and Glazing Ratio
  • Solar Control — Shading
  • Daylighting Access and Controls
  • Energy Management Systems
  • Building Dashboards
  • Radiant Heating/Cooling and Chilled Beams
  • Plug Load Reductions
  • Energy Recovery Systems

Zero-energy resources

In addition to the Zero Energy Project List, NBI released a new online tool that offers users access to information about the ZE buildings on the list and shows where they’re located on a map. The dynamic database allows searches on location, size and building type, and generates charts and graphics conveying the appropriate information.

To access the NBI resources, visit the links below:

NBI partnership with ASHRAE

NBI also just announced a new partnership with global sustainable building technology group ASHRAE to optimize the design, energy performance and emission reductions of buildings. More information is on the NBI website.