CA Building Code Takes Big Step Toward Net-Zero Energy

12/5/2018: The California Building Standards Commission voted unanimously today to confirm the 2019 update of the state’s building energy efficiency standards, as adopted by the California Energy Commission in May earlier this year. They become effective January 1, 2020.

How would you like living in a home with a dramatically reduced electric bill? That will be a reality for most new homes in California starting in 2020, thanks to a new building energy code adopted today by the California Energy Commission. The updated code—the first of its kind in the nation—will combine rooftop solar panels with enough energy efficiency measures like insulation and better windows that all new single-family homes and low-rise apartments will use net-zero electricity. This means that their solar array should offset all electricity use for cooling, plug-in equipment, and lighting on an annual basis.

Image courtesy of Wakeland Housing and Development Corporation

The groundbreaking decision to make these new homes net-zero electricity, coupled with major savings from more efficient lighting required by the updated code for commercial buildings, will save Californians more than $1.7 billion in net energy savings over the next 30 years and reduce carbon pollution statewide by 1.4 million metric tons. This is equivalent to the emissions from the annual electricity use of all households in the city of San Francisco.

Energy use in buildings is responsible for one-fourth of the greenhouse gas emissions in California. There are a lot of new residential units built each year, nearly 120,000 in 2017 alone, roughly evenly split between single-family and apartment buildings. But currently, only 15 to 20 percent of new single-family homes have solar panels.

That makes building energy codes, which California updates every three years, a powerful opportunity to reduce the state’s carbon pollution over time, while helping with housing affordability. Better insulation and windows required by the 2020 code, combined with solar panels, will reduce energy use in single-family homes by a whopping 53% compared to current code. This will prevent 700,000 metric tons of carbon pollution—the equivalent of zeroing out emissions from 115,000 cars.

Walls, insulation, piping, and other building infrastructure last for decades. It is a lot cheaper to build them right the first time than to have to rip open the walls later to upgrade them. This avoids locking Californians in high pollution and utility bills for decades.

Under the new code, which goes into effect in January 2020, all new single-family homes and low-rise apartment buildings will be required to install solar panels, or tap into community solar power, to compensate for all electricity used by the building. (Homes that truly are not suitable for solar, e.g., shaded by trees or large buildings would be exempt.) A modestly-sized system will do, because builders must first meet energy efficiency standards, using highly efficient attics and walls, better windows and doors, and properly installed insulation, to ensure that new homes require little heating and cooling to keep them comfortable.

The code also encourages builders to install energy storage, such as home batteries or flexible electric water heating, which allow residents to use more of their own clean energy solar electricity at home as needed instead of automatically sending it to the grid. This helps integrate renewable energy on the grid by storing solar electricity when it is abundant for later use in the evening when demand is higher and solar is no longer generating.

The code covers non-residential buildings too: our new office buildings, hospitals, schools, hotels, and restaurants will be getting more efficient too, with roughly 30 percent energy savings, mainly due to more efficient lighting.

Helping with Housing Affordability

Homes prices and rents are through the roof in several areas of California, and many are rightfully concerned about anything that might exacerbate this situation. The good news is that these new building standards will actually make new homes more affordable from day one. Between the solar array and the efficiency measures, residents will save roughly $1,000 in annual utility bills, while only paying $40 per month for the measures on a 30-year mortgage, for a net saving of $480 annually at no extra cost upfront when fully financed.

In addition, the new code removes the disincentive for builders to use high-efficiency electric space and water heating, an outdated feature of the current code dating back to the 1990s when California’s electricity grid was dirtier and electric heating was less efficient. By unlocking the use of highly efficient electric space and water heating, residents can now leverage their solar energy to reduce not just cooling, plug-load, and lighting costs, but also their heating and hot water costs, slashing total energy bills by half or more. In fact, a developer currently advertises an 80 percent reduction in energy bills from all-electric homes with solar in West Oakland.

The updates will be particularly welcome relief for low-income Californians, who spend twice as much on energy per dollar of income than the statewide average. Efficiency upgrades provide relief from high energy bills and make affordable housing more comfortable.

Great Progress, but More Needed  

Zero-net electricity falls short of zero-net-energy and more importantly of zero-net-emissions. The new code doesn’t fully address one large remaining source of energy use in homes: the direct, onsite combustion of fossil fuels like natural gas and propane for space and water heating, which represent more than one-third of emissions in the building sector.

These emissions must be reduced significantly to achieve California’s goals (and what science tells us is necessary to keep global temperatures from rising by more than 2 degrees Celsius) of cutting emissions by 40 percent by 2030 and 80 percent by 2050. The Energy Commission should adjust the focus of the next triennial revision of the building code from zero-net energy to minimizing emissions, in alignment with our pollution reduction and climate stabilization goals.

The new code still needs to be approved by California’s Building Standards Commission, which will consider the proposal at a December 2018 hearing and is expected to approve it.

California once again serves as a model of smart and effective climate and clean air policy. By implementing policies that will protect consumers, including low-income communities, while cutting pollution, California is showing the world what clean energy action looks like. 

About the Authors

Pierre Delforge

Director, Clean Buildings, Climate & Clean Energy Program

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