Why Switch To Electric?
A Heat Pump Water Heater Is Better For Your Family, Your Home, And Your Community.
Compare Different Types Of Water Heaters:
| Heat Pump Water Heater | Gas Water Heater (Tanked) | Gas Water Heater (Tankless) | Electric Resistance Water Heater | |
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| Description | A water heater that uses electricity to move heat from the air into your water tank. | A water heater that burns gas to heat your water tank. | A water heater that burns gas and heats water immediately as the water flows through a pipe. | A water heater that uses electricity to heat your water tank. |
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| Emissions | None | NOx | NOx | None |
| Typical Tank Size (2 Bedroom | 65 Gallons | 40 Gallons | N/A | 40 Gallons |
Resources For Making The Switch
Discover Resources Available To Help You Protect Your Family And Modernize Your Home.
WestLight Energy (Formerly Peninsula Clean Energy) Offers Rebates For Switching from Gas To Electric.
Did You Know? The Bay Area Air District Is Phasing Out The Purchase And Sale Of Appliances That Have Harmful Emissions.
The Permitting Process in San Mateo County
Permits are required in all San Mateo County jurisdictions when installing a new or replacement water heater. Following the permit process ensures that all equipment is installed safely and correctly. You will also need to submit your permit to qualify for most rebate programs. These resources walk you through getting a permit for a smooth replacement of your gas water heater with a heat pump water heater.
The permit process varies slightly depending on the jurisdiction, but all follow the same basic steps:
- The permit applicant gathers all information needed for permit submittal.
- Submit your permit online or at your building department counter and pay the permit fee.
- After submission, your permit will either go through an express permitting process, or may go through plan review for more complicated projects.
- The jurisdiction issues the permit once all details are reviewed and approved.
- The contractor completes the installation. They will haul away your old water heater and correctly connect the piping for your new heat pump water heater. They may install an outlet for your heat pump water heater if the existing outlet needs an upgrade. For emergency replacements, your contractor may complete the installation first and apply for a water heater permit afterwards.
- Work with your jurisdiction to schedule an inspection. Most San Mateo County jurisdictions require a physical inspection, although some jurisdictions offer virtual inspections
- After the project passes inspection, it is complete.
Use this to find resources in your jurisdiction and apply for your permit.
- Your jurisdiction will request information such as name, address, and project description. Some jurisdictions request a drawing of the water heater location, electrical calculations or diagrams, or the manufacturer specifications of the water heater.
- This checklist shows what inspectors look for to make sure your water heater replacement is safe and efficient.
Homeowners or contractors can apply for the permit.
Several state and local groups provide lists of contractors who install heat pumps. Find the right one for your home through:
For simple water heater installs, most jurisdictions can get your permit to you instantly, or within a few days through express permitting. If your project is more complex, it may take longer to get the permit issued.
In San Mateo County, most permits are between $100 and $300. See your jurisdiction’s fee schedule for more details on the exact cost. In Atherton and Burlingame, permits are free when replacing a gas water heater with a heat pump water heater.
A heat pump water heater may require a slightly larger tank size. Learn more about sizing a heat pump water heater in your home from Silicon Valley Clean Energy.
96% of homes can install a heat pump water heater without upgrading their electrical service. Read more information about panel upgrades below.
Upgrade Your Water Heater, Not Your Electrical Service
96% of homes can add a heat pump water heater without upgrading electrical service. Source
Want to skip the load calculation? If you are a WestLight Energy customer, you can email them to request your home’s peak load data, which will show your available electrical load capacity. Use this email template to request your data, and include your data with your permit application to show that your home can handle the increase in electric use from a heat pump water heater.
Changes On The Horizon
And here’s the bonus: the Bay Area Air District’s Rule 9-6 will require most new water heater sales to be zero-NOx starting in 2027. Making the switch now puts your home ahead of the curve and keeps future replacements simple.
Learn more from BayREN, Energy STAR, Switch is On, Bay Area Air District and TECH Clean CA.
Going electric at home doesn’t just clean up your air — it helps clean up everyone’s air. In 2019, emissions from residential natural gas combustion produced more NOx than fuel refining or passenger vehicles across the entire Bay Area. Zero-NOx heat pump water heaters cut pollution at the source, in your home and your neighborhood.
The County of San Mateo Sustainability Department is hosting a free tire recycling drop-off event for San Mateo County residents. There is a limit of 9 passenger or light truck tires per vehicle, as required by state law. Tires accepted at this event must be size R19.5 or smaller, with or without rims. Please ensure the tires are deflated. Tires from commercial, auto repair, and/or salvage businesses will not be accepted.
- Location: 1 Library Ave, Millbrae, CA 94030
- Date: August 22, 2026
- Time: 10:00 AM – 2:00 PM
- Collector: San Jose Conservation Corps
Questions?
- Call 888-442-2666
Residents must provide proof of residency in San Mateo County (e.g., driver’s license, utility bill, garbage collection bill, etc.).
For larger truck tires (tractor, truck etc.) contact the Sustainability Department at 888-442-2666 for recycling location information or visit www.recyclestuff.org.
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