Growth of Zero Energy Buildings

New Buildings Institute (NBI) has been tracking zero energy (ZE) buildings for more than a decade now. In the first Getting to Zero Status Update published by NBI in 2012, we proudly reported 60 commercial and multifamily buildings or projects that were either Verified by NBI as having achieved zero energy performance or were Emerging to that level. Today, our free, interactive Getting to Zero Buildings Database (newbuildings.org) maps more than 650 zero energy buildings across North America: that’s over 1000% growth in 10 years!

The 650 ZE buildings known to NBI today represent the tip of the iceberg. For a variety of reasons, from market forces to policy and regulatory drivers, ZE buildings are coming soon to a lot near you. These trailblazing projects and teams show the way to achieve high performance in the built environment, and we can all learn from their experience— whether a project offsets its energy use with on-site renewables or not. Even projects that haven’t set a zero energy or zero carbon goal can learn from these pioneers to deliver a high-performance, deeply efficient building at no or minimal cost premium.

Zero energy buildings transcend climates and borders in North America with projects occurring in 44 of the U.S. states and four of the 10 Canadian Provinces. California is by the far the front-runner in ZE building activity, with the San Diego and Los Angeles areas being the densest clusters in the state. The San Francisco Bay area and Silicon Valley form another large cluster, followed by the Portland, Ore., metro area and the North Atlantic coast.

What Trends Are Driving This Growth in Zero Energy Buildings?

This growth is driven by a handful of major forces: policy at the state, local, and federal level, a precipitous decline in solar panel costs, and enhanced awareness among designers and building owners of the need for deeper efficiency in buildings. Dozens of leading jurisdictions from California to New York have enacted carbon neutrality commitments, usually through executive orders or legislation. As of January 2020, 3,850 mayors, county executives, governors, tribal leaders, college and university leaders, businesses, faith groups, and investors have declared “We are Still In” on the Paris Agreement.

What does this mean for buildings—and metal buildings in particular? These policy shifts are pushing designers, builders and other industry players to deliver higher-efficiency buildings. Energy codes are driving better efficiency in buildings and electrification.

In California, all new low-rise single-family and multifamily buildings are now required to have a rooftop solar system—in addition to deep energy efficiency requirements in the new energy code. Some details aside, this basically constitutes a zero-energy requirement for all new homes in California.

Energy codes are evolving outside of California, as well. Recently, NBI announced that the efficiency gains realized in the 2021 International Energy Conservation Code (the model energy code referenced by many states across the country, although not California) were on track to increase by 10% or more. Readers of Metal Construction News and Metal Architecture may be particularly interested in a few key code and policy trends:

• The minimum required insulation for wood and metal frame building roof and wall assemblies increased in the colder climates (Climate Zones 4-8 for roofs and 5-8 for walls).
• The optional solar-ready code appendix has evolved to include solar plus storage. Structural requirements for roofs to be solar-ready will need to be considered more and more.
• Embodied carbon is emerging as a consideration. Marin County, Calif., recently adopted the first building code in the nation limiting the carbon emissions from concrete in buildings.

Embodied Carbon is Becoming a Bigger Share of Emissions

As we drive down operational energy use in buildings, embodied carbon is becoming a bigger deal for addressing climate change, and it is now becoming a bigger focus in the building industry. The new Embodied Carbon in Construction Calculator (EC3) (www.carbonleadershipforum. org) tool is one of several tools that allow design teams to calculate the embodied carbon in the materials they are selecting.

It’s less about cost and more about cash flow. My net zero village cost more at construction but is delivering net positive income.

David Bruns, New York multifamily real estate developer

For metal in particular, embodied carbon can vary enormously. Just look at Colorado’s Evraz Steel Mill, which produced most of the steel rails used to link the American West. Evraz is building a solar farm that will generate 95% of its annual electricity demand and undertaking other upgrades that will help this historic and storied steel mill will reach near-zero energy performance in is manufacturing processes in the coming years.

Building-Grid Integration Must Be Addressed As More Renewable Generation Comes Online

The role of buildings, renewable energy, and energy storage in the utility industry is also changing. NBI is leading the GridOptimal Buildings Initiative: a collaborative, multi-stakeholder effort to develop metrics to define the quality of building-grid interactions. GridOptimal will support the least-cost decarbonization of the grid through better integration of distributed and utility-scale wind and solar energy. The metrics, design guidance, programs, and policy leadership that are becoming available through GridOptimal will play an important role in catalyzing the transformation of buildings and the grid. GridOptimal is in active development now (early 2020) and NBI is now seeking projects interested in piloting GridOptimal metrics and guidance.

The Cost of Getting to Zero is Coming Down as Design Team Knowledge Improves

When it comes to added cost, getting to zero in new construction projects dropped from roughly 20% of the project budget in 2009 to being reported as 0% to 4% of the project budget on more recent projects, according to a recent report by stok, an integrated real estate services firm in San Francisco. There are dozens of very detailed case studies of buildings across the U.S. that have been built to ZE, including many that delivered ZE at no additional cost beyond the client’s standard budget. Design firms competing for public client projects should put ZE in their offerings—many firms have offered this as a value-add in their bid within the program budget to help the public client meet climate action plan goals. Likewise, private developers see that there is money to be made from going ZE.

Educational Facilities Are a Leading Market in Getting to Zero

One-third of the ZE projects in NBI’s Getting to Zero Buildings Database are educational facilities. These leading schools, community colleges, universities, and workforce training centers shape the educational landscape dramatically. Is there something specific to metal construction in schools? For example, students in classrooms with natural light showed a 20-26% improvement on test scores compared to artificially lit environments, according to an NBI study. With students spending approximately 1,000 hours per year in a school, transforming classrooms into healthy and productive spaces is of the utmost importance.

Zero Energy and Zero Carbon Buildings Today and Tomorrow

Zero energy and zero carbon buildings are a fast-growing trend. The scale of projects has evolved from small demo buildings to very large projects, districts and campuses, and even a ski resort. Policy trends are quickly shifting as leading codes and policies require the top end of what’s possible. The low-energy outcomes and targets of ZE buildings known today reflect what can be done in today’s market, and we can expect more innovation ahead. As the pressure of impacts from the climate crisis grows, NBI expects these trends to accelerate.

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Alexi Miller is a senior project manager at the National Buildings Institute (NBI) and is NBI’s lead engineer. Alexi leads several programs and initiatives, including Zero Energy Building Certification, the GridOptimal Buildings Initiative, Public Buildings Portfolio Management and the Getting to Zero Buildings Database. He is a licensed engineer in the state of Oregon.