Can California Wring Carbon Emissions Out of Buildings? So Far the Pace Is Slow

Building decarbonization: to remove greenhouse gas emissions from a building’s energy use, achieved through making the building more efficient and integrating appliances powered by clean energy sources. —California Building Decarbonization Coalition

For decades, minimizing and eventually eliminating fossil fuel has been the Holy Grail of California’s quest to clean up smog and cut emissions that cause global warming.

Yet even after decades of concerted effort to advance renewable power—like wind and solar—and transition to electric vehicles, California’s vast population and economy still released almost 420 million tons of greenhouse gases in 2019, according to the California Air Resources Board.

There’s little doubt that in its drive to eliminate greenhouse gas emissions, California has had its biggest success with the electric industry. Today California Energy Commission data show that more than 34 percent of all the state’s power is renewable, not counting power from hydroelectric dams. By 2030, the power industry aims to hit the 50 percent renewable mark, while keeping hydropower at similar levels.

Reducing GHGs Means Cutting Building Emissions

Yet, to cut greenhouse gases 40 percent by 2030 and 80 percent by 2050, state environmental and energy agencies can’t ignore commercial and residential buildings. Together these two types of structures produce 26 percent of total state greenhouse gas emissions, according to the Building Decarbonization Coalition. By comparison, industry emits 27 percent, transportation 37 percent, and agriculture 9 percent.

Building emissions are that large because they cause carbon emissions in three ways. First, buildings are major users of electricity from the grid, which is not yet carbon-free. Second, refrigerants used in air conditioners and other devices leak into the atmosphere, where they trap the sun’s energy. Finally, space and water heaters and cooking devices burn natural gas, which emits carbon dioxide (see pie chart for a breakdown of gas uses in buildings).

That’s why virtually all agree that California can’t meet its greenhouse gas reduction goals without paring down emissions attributable to buildings. But there’s no unanimity on how to do so.

The effort started in the last decade, when the California Energy Commission set out to require new structures to reach a “zero net energy standard.” Under that approach, they would have to produce as much solar energy as they use from the power grid and from burning natural gas combined. However, the commission fell short of zero net energy in developing efficiency standards for new buildings that took effect in 2020. It simply couldn’t determine what to do about use of natural gas.

So enter a new concept—building electrification. “Thanks to California’s proactive transition to carbon-free renewable electricity, this can be achieved by converting appliances that are currently powered by fossil fuels to already available technologies powered by electricity,” maintains Panama Bartholomy, executive director of the Building Decarbonization Coalition, a prime advocate for banning natural gas hookups for new buildings.

Pushback

But the push has triggered the state’s natural gas utilities to cry, “What about us?” Facing the prospect that a ban will sting them financially, SoCal Gas and other gas utilities are fighting back by promising to fill their pipelines over time with increasing amounts of renewable natural gas—methane from landfills, wastewater treatment plants, and animal feedlots. They also hold out the prospect that they will use renewable electricity to produce hydrogen from biogas and water, which can be burned as well as used with fuel cells to make electricity.

“We are currently investing in a diverse portfolio of technologies and applications to leverage Southern California’s gas grid to transport low- to zero- (and even negative-) carbon molecules, such as renewable natural gas and hydrogen,” according to Kevin Barker, SoCal Gas senior manager for energy and environmental policy, last month. And Scott Drury, company chief executive officer, promised earlier this year that SoCal Gas will deliver gas that’s 20 percent renewable by 2030 and reach net zero emissions by 2045.

Pathways and Prospects

While renewable natural gas in the pipeline may finally become a reality, it comes only after decades of discussion and study that so far have not panned out. However, with different pathways posed to cut emissions, the concept of building electrification has morphed into building decarbonization. How to advance decarbonization is, perhaps, the key issue the California Energy Commission faces as it conducts its biannual building energy efficiency standards update for 2022.

Meanwhile, while the commission looks for a statewide path forward, more than fifty cities in California have restricted gas hookups for use in new buildings or are actively weighing whether to adopt restrictive ordinances, according to the Sierra Club. Berkeley led the local charge by adopting an ordinance in 2019 to phase out gas hookups in all newly constructed residential buildings and most nonresidential buildings. Since then, cities large and small, from San Francisco and Sacramento to Ojai and Petaluma, have taken action to restrict or constrain use of gas in new buildings.

In the offing, too, is potential action by additional cities that have measures in their climate action plans to restrict gas appliances in new construction. Locally, for instance, South Pasadena has several building decarbonization measures in its plan. The plan calls for making sure 100 percent of all new construction is eventually all-electric. It even calls for seeking to retrofit 5 percent of all existing buildings to be all-electric by 2030 and 80 percent by 2045. Retrofits would largely be accomplished through financial incentives and public education. Since the city adopted the plan late in 2020, building decarbonization efforts remain to be scheduled for adoption.

Back at the state level, a bill to incentivize building decarbonization with energy utility ratepayer funds—SB 31 by Senator Dave Cortese (D-San Jose)—failed to advance earlier this year. It met stiff opposition from pipefitters and plumbers, who install the pipe systems in buildings that carry natural gas.

While many areas of the nation have featured all-electric homes for decades because they lack natural gas distribution pipelines, moving to all-electric decarbonized buildings in California remains controversial due to giant vested interests—the renewable energy industry on one hand and the natural gas utility industry and its workers on the other.

Not surprisingly, then, building decarbonization—originally conceived of as zero net energy use a decade ago—continues to advance at a glacial pace in a world where glaciers are quickly disappearing.

—William J. Kelly, Natural Resources Committee

William J. Kelly has written about the environment and energy for forty years, including as communications manager for the South Coast Air Quality Management District and before that as a reporter in Washington for what is now Bloomberg-BNA. He has authored several books on the environment, including Smogtown: The Lung-Burning History of Pollution in Los Angeles and The People’s Republic of Chemicals.