It’s becoming ever more clear that buildings are having an outsized impact on global greenhouse gas (GHG) emissions. Most buildings run on multiple fuels — electricity to power lights, refrigerators, electronic devices; and fossil fuels, such as natural gas (methane), primarily to power furnaces and water heaters. It’s the use of natural gas in buildings that is responsible for about one quarter of Marin’s GHG emissions. Building electrification is the shift away from fossil fuels combustion toward the use of clean electricity for space and water heating, as well as for appliances.

A transition to all-electric buildings will not only reduce harmful climate impacts, but it will improve indoor air quality and have health benefits such as reducing asthma rates over a building’s life span. Building electrification plays an important role in fulfilling goals to reduce GHG emissions in local climate action plans and in moving forward on the path to a clean energy future.

High-efficiency heat pumps are fueling the shift

Building electrification is a viable alternative because fossil fuel-powered appliances and equipment already have electric substitutes. High-efficiency electric heat pumps are the enabling technology for space and water heaters — they are three to five times more energy-efficient than their natural gas counterparts. Unlike conventional furnaces, which burn fuel to produce heat, heat pumps use electricity to transfer thermal energy between spaces, sending heat where it’s needed, or removing it from where it’s not. They offer a two-for-one benefit: heating and air conditioning from the same equipment.

Future new homes built with electric heat pumps, a tightly insulated building envelope, and rooftop solar will have smaller energy demands, be energy efficient, and will substantially decrease carbon emissions. Electric heat pump space and water heaters can also be installed in existing homes and are the clear choice to reduce greenhouse gas emissions when old gas-fueled units need replacement.

Air Source Heat Pump
Collaborative Efficiency

The IPCC report: The need to accelerate

We know that global warming is caused mostly by human activity, primarily from burning fossil fuels, and that a large percentage of GHG emissions comes from the building sector, not only in Marin, but nationwide. We also know that impacts from growing climate change are affecting weather patterns, increasing environmental hazards, harming biodiversity, and increasing economic and human hardship, especially for the world’s most vulnerable. The IPCC’s recently released Climate Change Mitigation Report (April 4, 2022) emphasized the need to accelerate climate actions if we are to prevent the worst impacts of climate change.

The 2022 IPCC report is the latest of three. It reports that with every fraction of a degree of global warming, climate change impacts will intensify, and it calculated that the world must peak GHG emissions within the next three years to preserve chances of meeting the Paris Agreement’s 1.5 degrees C (2.7 degrees F) target. Exceeding that threshold, even temporarily, will result in more severe and often irreversible climate impacts, and create a greater need for carbon removal, making early emissions reductions to avoid overshoot critical.

According to the IPCC, we must cut emissions by half by 2030. Transformations across all major sectors are needed. Among the report’s recommended actions for mitigation are incentivizing green buildings, electric heating, and more efficient appliances and lighting; rapidly retrofitting older buildings with improved technologies; incorporating those technologies in all new construction projects; and scaling up clean energy. Transitioning to lower emission lifestyles can make an enormous difference. The time to influence policymakers and to take personal action is now.

Updating Marin’s Green Building Codes

Every three years the California Energy Commission (CEC) updates the state’s Energy Code. In August 2021, the CEC adopted the 2022 Energy Code. In December, it was approved by the California Building Standards Commission for inclusion into the California Building Standards Code effective January 1, 2023. In summary, the new State standards improve upon standards and guidance for electric heat pump technology, electric-ready requirements, solar photovoltaics + battery storage, and indoor air quality. All jurisdictions must adopt the State’s building standards as a minimum. Cities and counties may alternatively choose to adopt local building codes that “reach” beyond the state minimum.

Currently, all twelve of Marin’s jurisdictions are jointly working to develop a model reach code ordinance that would exceed the State building standards. The focus of the Green Building reach code is a ramping down of the use of natural gas in buildings. The model reach code will require new residences to be all-electric, and remodels to meet a target energy score that allows for a range of options that could favor electric heat pump space and water heaters as long as they are cost-effective. The County is also expanding its incentives and rebates programs, such as Electrify Marin that connects residences and businesses to State, regional and local financial incentives should owners decide to voluntarily replace gas-fueled space and water heaters with electric heat pump models when they reach the end of their useful lives.

The joint effort is being led by the County of Marin, San Rafael, San Anselmo, and Marin Clean Energy (MCE) with the goal of developing and simultaneously adopting a consistent reach code countywide. The joint effort provides smaller jurisdictions an opportunity to leverage County, regional, and State staff and resources. [Fairfax has already adopted an all-electric ordinance for new construction.] Having consistent Green Building reach codes across jurisdictions would make it easier for contractors and enforcement to comply. If adopted, the reach codes will amend each jurisdiction’s local building requirements and, in concert with the State’s standards, would go into effect January 1, 2023.

Planning for development: a unique opportunity to make a difference

The Association of Bay Area Government’s Regional Housing Needs Allocation calls for more than 14,000 additional homes to be approved in Marin County between 2023 and 2031. If supplied with natural gas-burning space and water heaters, these units would worsen greenhouse gas emissions by emitting thousands of additional tons of GHG emissions per year. (This includes methane leaks in pipelines and at the meter that have a much greater potency than carbon dioxide and, ton for ton, warm the Earth as much as 84 times more than CO2.) In addition, there are over 113,000 existing housing units in Marin, most with gas furnaces and water heaters that have an average life span of 15 years. That’s well over 10,000 replacement opportunities each year to potentially switch to electric heat pump units. Achieving uniform countywide adoption of the Green Building reach code could significantly change the building sector’s outsized impact on GHG emissions, at least in Marin.

What you can do:
  • Gather information and support the Green Building reach code initiative in your town.
  • Encourage your jurisdiction’s staff and council members to take part in the County-led effort to encourage consistent Green Building reach codes across all jurisdictions.
  • Ask that a Green Building reach code update be added to an upcoming Council agenda so your city or town’s participation in the joint process can be discussed in a public forum. • Join others in meeting with your district Supervisor.
  • Regularly speak up during public comment at Council and Board of Supervisor meetings. • Participate in public workshops conducted by the County. [Marin County is planning a public workshop, coming soon, likely in June.]
  • Send letters supporting the Green Building reach code to local newspapers.
  • Be the change. When it comes time to decommission your gas-powered appliances, space or water heaters, replace them with high-efficiency all-electric heat pump models. If you haven’t already, switch to MCE’s Deep Green to support solar, wind and other clean power. Optimize the insulation of your home’s heated and cooled spaces to maximize energy efficiency.

Excerpt from May-June 2022 MCL newsletter

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