A new important study “Scenarios to Decarbonize Water Heating in California” has sobering news: California will not achieve it’s 2030 or 2050 climate stabilization goals unless we dramatically cut the use of gas in our homes and buildings. I recently sat down with lead researcher, Shuba Raghavan to learn more.
Sierra Club: What’s the main thing policymakers should understand from your research?
Shuba: We are rapidly approaching 2030 without the policies in place to achieve the state’s climate goals. California has implemented several important climate regulations, including SB 32, which mandates a statewide GHG reduction of 40% below 1990 levels by 2030. While existing policies appropriately aim to cut GHGs from electricity generation and vehicles, there is a major policy gap when it comes to reducing GHGs from the pervasive use of gas in homes and buildings. Our research finds that we cannot wait until 2030 to begin decarbonizing buildings. That is too late. Specifically, we have to start replacing our gas appliances with very efficient electric models as early as 2020.
Sierra Club: Among all the big sources of pollution to clean up, like trucks and power plants, why do you focus on water heating?
Shuba: For the state to meet its climate goals, we cannot give any sector of the economy a free pass to keep producing carbon. We are seeing a lot of progress and attention to decarbonizing the electricity and transportation sectors. On the other hand, buildings which make up over 10% of California’s emissions have a lot of potential for sizeable GHG reductions, but they get little attention. In a way, buildings-- especially water heaters-- are the low-hanging fruit. Water heaters get replaced nearly every decade. So every year, about 1 million residential water heaters are replaced in California. That’s a big opportunity to cut carbon.
Sierra Club: We hear the gas industry talk a lot about the role of “renewable natural gas” in decarbonizing pipelines and buildings. How feasible is this?
Shuba: Gas companies talk about decarbonizing pipelines, but this is very difficult. There are over 13 million households in California, and about 90% of these homes use natural gas for water heating, space heating, and cooking. Given the limited availability of bio-methane in California and the uncertainty in the costs associated with biomass supply and gasification, it is very difficult for “renewable gas” to fuel all of these homes. Plus, biomethane still has the same air pollution problems -- like NOx and SOx-- as natural gas. From the analysis I’ve seen, the best option by far is to electrify the building sector, by leveraging the state’s steadily decarbonizing electricity.
Sierra Club: How will electrifying water heating affect homeowners and renters in California?
Shuba: Reliability wise, there will be no impact. You’ll have the same hot showers and won’t notice a difference. Actually, given the extreme weather conditions we are facing coupled with methane leakage from gas pipes, having an all-electric home might be much safer and more reliable than gas. In terms of cost, installing an electric heat pump coupled with rooftop solar makes good economic sense. Without solar, it really depends on your utility and rate structure. If you are replacing an electric resistance water heater, then you can cut your water heating bill by a third by getting a super-efficient heat pump. Finally, small changes to electricity rates at the CPUC can enable residents to save money with electric water heating and motivate them to use their electric appliances when there is lower cost solar and wind on the grid.
Sierra Club: Are there other benefits to electrifying water heating besides GHG reduction?
Shuba: Yes, for sure. Improved air quality and health are major benefits of electrification. Gas appliances like gas stoves, water heaters and furnaces release nitrogen oxide, carbon monoxide, formaldehyde, fine particles and other pollutants that are bad for indoor air quality. Researchers at LBNL have uncovered the harmful air quality and health impacts of gas stoves especially. And, of course, all-electric homes will not only improve indoor air quality, but will also reduce risk of fires from leaky gas pipes and an indoor flame.
Sierra Club: Where are we seeing progress with building electrification?
Shuba: We are seeing some great leadership from some utilities, Community Choice Energy (CCE) providers, cities and Air Districts. SMUD and Palo Alto offer the highest rebates in the state -- up to $1500 for homeowners to purchase an electric heat pump water heater. Marin Clean Energy, Sonoma Clean Power, and other CCEs are also launching programs to support beneficial electrification. And, Southern California Edison recently released an important white paper that shows why electrification is the preferred pathway to achieve California’s 2030 climate goals. Similarly, the Bay Area Quality Management Control District’s Clean Air Plan calls for electrifying gas end uses in buildings. We are also seeing a growing number of cities across the state support building electrification through workforce training and homeowner education and outreach programs. So, there is lots of important activity, but we still lack a coherent statewide policy framework to electrify homes and buildings across the state.
Sierra Club: What’s needed to get California moving towards zero-emissions all-electric buildings?
Shuba: Ultimately, we need new policies to drive a large scale shift away from gas to cleaner, safer, more efficient electric buildings. Specifically, we need the CPUC to make energy efficiency rebates available for homeowners that want to replace gas furnaces and gas water heaters with more efficient electric models. Electricity rates also need to be updated to ensure electrification is affordable and supports deeper integration of renewables onto the grid. We also need the CEC to update the state’s building energy code (Title 24) to support construction of all-electric buildings. Lastly, there’s a need for public education, so people more broadly recognize the clean energy, climate, and air quality benefits of electrification. Cities, utilities, advocacy groups, academics, plumbers and contractors, architects, and of course state policymakers all have an important role to play in creating this clean energy transition off of gas. To succeed, we need all hands on deck.