A smart thermostat saves 10–15% on heating and cooling by learning your schedule and avoiding conditioning an empty home. Unlike most energy upgrades, this one requires zero landlord permission in most cases — you’re replacing an existing thermostat (temporary improvement) and can restore the old one when you leave.
Most California utilities offer rebates of $75–$150, which can cut your payback to under a year. Some programs — like PG&E’s SmartAC — will even give you one for free in exchange for minor demand-response participation.
PG&E, SCE, and SDG&E all run programs where you get a free smart thermostat in exchange for allowing the utility to briefly adjust your temperature during grid emergencies. Events are rare, the temperature change is small, and you can opt out of any individual event. Worth checking before you buy.
Smart thermostats work with most central HVAC systems but have specific wiring requirements. The key thing to check: does your current thermostat have a C-wire (common wire)? It’s usually labeled “C” on the thermostat base. If not, the Ecobee comes with a PEK adapter that solves this. Nest has a built-in battery that often works without a C-wire.
Both Ecobee and Nest have compatibility checkers that walk you through this:
Before spending $200, check if your utility is giving them away. These programs offer qualifying customers a free Ecobee or similar device in exchange for joining a demand-response program. Enrollment is quick online.
If you didn’t get one free: the Ecobee SmartThermostat Premium (~$250) is the best overall — it comes with a room sensor, has the best compatibility, and has the highest utility rebate rates. The Google Nest Thermostat (~$130) is the most popular and easiest to install but has no room sensor.
Turn off the HVAC breaker. Take a photo of the current wiring. Remove the old thermostat. Connect the wires to the labeled terminals on the new base (the photo is your reference). Snap the display in, restore power, follow the app setup. Both Ecobee and Nest have excellent step-by-step video guides.
After installation, submit your receipt to your utility for a rebate of $75–$150. Most have an online submission form. Keep the original packaging for 90 days in case of any issues.
Best compatibility, includes room sensor, Alexa built-in. Highest rebate rates from utilities.
Shop on Amazon →Easiest install, Google Home integration, sleek design. No room sensor. Most popular model.
Shop Google Store →Mid-tier Ecobee, no room sensor included but compatible. Good balance of price and features.
Shop on Amazon →The original smart thermostat. Auto-schedules itself. Premium stainless design.
Shop Google Store →