California's climate, for sizing
- IECC climate zone
- 3B-5B (varies sharply) · coastal mild / inland hot / mountain cold
- Typical winter low
- 35°F to 50°F (most), 15°F to 25°F (Sierra)
Climate zone depends entirely on county. Coastal homes barely heat; Central Valley swings hot and cold; Sierra households need cold-climate equipment. Match the model to the actual zone, not the state name.
California state and utility programs
- HEEHRA (via TECH Clean California) (Income-qualified rebate): up to $8,000. Income-qualified single-family households. FULLY RESERVED STATEWIDE as of Feb 24, 2026 — new reservations on waitlist pending additional funding. Multi-family properties may qualify up to $14,000. California Energy Commission
- TECH Clean California (Contractor-channel incentive): $1,000–$3,000. Statewide incentives delivered through trained contractor network. Cannot stack with HEEHRA on the same project. Open to all California homeowners. TECH Clean California
Federal programs that still apply
- Section 25C Tax Credit (Tax credit (EXPIRED)): EXPIRED Dec 31, 2025. Repealed by the One Big Beautiful Bill Act (Public Law 119-21, July 4, 2025). Installations placed in service on or before Dec 31, 2025 may still claim on 2025 returns until Oct 15, 2026 extension deadline. 2026 installs are NOT eligible. IRS Energy Efficient Home Improvement Credit
- Home Electrification and Appliance Rebates (HEAR / HEEHRA) (Point-of-sale rebate): up to $8,000. Income-qualified households (≤150% area median income). 100% covered for ≤80% AMI, 50% for 80–150% AMI. State-administered with rollout varying widely. Some states (CA) fully reserved; others (HI, NH) launching mid-2026. US DOE Energy Saver Hub
- DSIRE Database (Aggregator): all state programs. Searchable database of every state, local, utility, and federal incentive currently active. Funded by US DOE, maintained by NC State University. Best starting point for verifying your specific ZIP code's options. dsireusa.org
Heads up: the federal Section 25C tax credit expired December 31, 2025. State and utility rebates are still active in most places.
Where to look next, for California
- ENERGY STAR Rebate Finder: utility-specific rebates by ZIP.
- DSIRE database, filtered to California: every active program in the state.
- Run the heat pump tools: payback, sizing, and whether the math actually works in coastal mild / inland hot / mountain cold.
- Stack the Money: the national overview, with what stacks with what.