Efficiency and Carbon Reduction Goals Converge at the Built Environment

With mounting evidence that immediate and aggressive action is necessary to address climate change, combined with a lack of leadership on this issue by the federal government, state and local governments are taking meaningful actions to adopt, honor, and meet the goals of the Paris Climate Accord. Twenty-three states have joined the U.S. Climate Alliance, which is a bipartisan coalition of states committed to reducing greenhouse gas (GHG) emissions consistent with the goals of the Paris Agreement. Local governments are also leading, with more than 400 Climate Mayors representing over 70 million Americans, having adopted the goals of the Paris agreement for their cities.

Through the development of climate action plans, most of these jurisdictions are setting policy targets for reducing greenhouse gas emissions (carbon dioxide is the primary greenhouse gas) rather than setting targets for direct reductions in energy use. With buildings accounting for up to 75% of carbon emissions in U.S. cites, it’s clear that addressing carbon emissions directly in the built environment is essential to meeting the goals of the Paris Agreement. Every decision – from the materials used to construct buildings to the type of energy used to power them – impacts the building’s magnitude of contribution to the climate crisis.

The city of Boulder is working to adopt a Net Zero Energy code by 2031.
Success will require a deliberate shift from delivering energy efficiency actions that result in energy savings to programs and policies that deliver carbon neutrality and overall GHG reductions. So how do we get there?

Building on lessons from energy efficiency programs
When the first utility-scale energy efficiency programs were being developed by utilities decades ago, early adopters saw them as a tool for driving better energy, economic and environmental outcomes. These regulated companies, to varying degrees, took up their role and succeeded in achieving energy savings goals. Likewise, the early writers and adopters of model energy codes viewed them as a way to ensure energy efficiency in both residential and commercial buildings and to create cost savings for business and residents. Both programs and codes worked to advance efficiency levels in the built environment. And it paid off.

To date, nearly all U.S. buildings, are regulated in the design of energy-efficient building envelopes and the installation of energy-efficient mechanical, lighting and power systems. These energy codes save consumers about $5 billion annually, according to the U.S. Department of Energy. Between 1992 and 2012, building energy codes resulted in a cumulative savings of about four quads of primary energy and 300 million tons of avoided carbon dioxide emissions. Ratepayer-funded energy efficiency programs now exist in all 50 states. In 2016 alone, electric efficiency programs in the United States and Canada avoided an estimated 21.4 million tons of CO2 emissions, according to savings estimates from the Lawrence Berkeley Lab (27.5 terawatthours converted to carbon savings, see Executive Summary page x).

Zero energy (ZE) buildings, which are ultra-low energy buildings that consume only as much power as is generated through onsite renewable energy resources (most often power solar photovoltacs) over the course of a year, are one additional market and program response to this call for action as reductions in energy inherently translate to lower carbon emissions. This building energy performance goal is becoming a more prevalent target. The 2018 count of ZE buildings across the United States and Canada has increased by 700% since 2012. A 2017 report by Grand View Research Inc. forecasts $78.8 billion of growth in the global ZE building market by 2025, compared to $8.04 billion in 2016.

More and more states and local governments are taking note of ZE buildings’ tangible, measurable goals and working them into climate action policies to achieve carbon reduction goals. AB3232 in California requires the California Energy Commission to find out how the state can reduce the emissions of greenhouse gases from the state’s residential and commercial building stock by at least 40% below 1990 levels by January 1, 2030. To help meet CA carbon goals, the new 2019 Title 24 residential energy code, all-electric homes will be ZE homes, while dual-fuel homes will be close to zero energy. New York is offering $1 million in incentives to support the design and construction of ZE buildings in an effort to meet Governor Andrew M. Cuomo’s goal to reduce greenhouse gas emissions 40 percent by 2030. Washington, D.C. will require Net Zero Energy for residential new construction by 2022 and commercial requirements are to be met by 2026. The city of Boulder is working to adopt a Net Zero Energy code by 2031. The list goes on.

Looking beyond kWh savings to a carbon metric
Discussion about ZE building policy is now moving directly to zero carbon (or carbon neutral or zero emissions) buildings. Carbon reductions are the goal after all, so why not call for that directly? For the past four decades, buildings have been regulated based on expected energy use, not carbon impacts. One primary challenge is that we have no broadly accepted mechanism for measuring building carbon emissions. Energy codes, which define standards for how buildings use energy, are fundamentally based on energy models. So how do we update energy codes to address the carbon emissions of buildings? Before we go there, we must define what a zero carbon building is.

We’re in the midst of a critical shift from delivering energy efficiency policies and programs that result in energy savings to programs that will deliver GHG emissions reductions and carbon neutrality in the building sector.

NBI is working with policymakers, code writers, practitioners and other organizations such as Rocky Mountain Institute to answer some of the big questions associated with how we define zero carbon buildings. Some of those challenges include:

  1. The policy churn created by a lack of federal leadership on climate change policy means jurisdictions are setting their own goals with their own metrics, and not all goals and metrics are the same. Measurement protocols now run the gamut from pure site energy, to source energy, and then onto source carbon reductions.
  2. Time of use matters. When you use energy, the time of day or season of the year can become just as important as how much energy you use. The source of the energy (wind, solar, hydro, coal) directly affects GHG emissions. If a ZE building is an electricity consumer from the grid on days when the sun is not shining and the grid has a higher carbon emission profile, overall emissions from the grid will not be offset with onsite generation.
  3. Measurement issues are rife. For instance, electricity grids are changing. Many jurisdictions have committed to 100% renewable grid electricity, or a 100% renewable portfolio standard (RPS), over the next few decades. How is this renewable energy “counted?” Do calculations include fugitive methane emissions from upstream production and downstream distribution of natural gas? There is no consensus on how to measure and quantify these impacts, both positive and negative, in building emissions metrics.
  4. National model energy codes are not keeping pace with the climate goals of many jurisdictions that want policies that directly and more rapidly reduce the carbon impacts of buildings, leaving them to amend and/or promulgate their own codes.

We’re in the midst of a critical shift from delivering energy efficiency policies and programs that result in energy savings to programs that will deliver GHG emissions reductions and carbon neutrality in the building sector. This is an exciting and dynamic time, but also a time when innovation and problem solving is desperately needed, much like the early days of model energy codes and utility-based energy efficiency programs. Just as we helped develop those programs and markets over the past 20 years, today we are hard at work developing the programs and metrics that will drive this next transformation in codes and policy and develop the market for low and zero emission buildings.

In the coming months, we’ll continue to tell the story of this transformation and publish additional blogs about how we’re working with other organizations to create the policies and programs that will set the course for this new generation of high-performance buildings—those that will deliver on the promise of climate action planning and goals and a carbon neutral built environment.

Jim Edelson, Director of Codes and Policy