How does Optiwatt's Event Temperatures feature work?

During a demand response (DR) event, which is a short window when your utility asks connected homes to ease off on power use, Optiwatt cools your home a little extra beforehand so your AC can mostly stay off while the event is on. You stay comfortable, but your AC does its work before the expensive, high-demand window instead of during it.

How it works

Optiwatt learns your home. Every home holds and loses cool air differently. Optiwatt learns yours from its own history, including how fast it warms up with the AC off and how fast the AC cools it down, and it tracks this by both outdoor temperature and time of day, since a house warms far faster under the afternoon sun than overnight. Hot, sunny afternoons warm a home fastest, so they call for the most pre-cooling. (If Optiwatt doesn't have much history yet, it uses sensible general estimates and gets more tailored over time.)

It cools only as much as needed. Optiwatt finds the warmest temperature your home can start the event at and still stay within your comfort limit the whole time with no cooling during the event, then times the pre-cool so your home hits that target right as the event begins. It never sets the target below your comfort range, and pre-cooling is capped at 3 hours, because on a very hot day, running longer would cost more than it saves.

A quick example

Say your cool setpoint is 74° and there's a DR event from 4 to 6 PM on a hot afternoon. Optiwatt figures your home should start at about 71° to coast to 6 PM without cooling, and that dropping from 76° to 71° takes about 50 minutes. So it begins cooling around 3:10 PM, hands off to the event at 4 PM, and your home gently drifts back up toward comfort during the event with little or no AC runtime.

By thermostat brand

Nest, Ecobee, and Honeywell all pre-cool ahead of DR events. 

Comfort and staying in control

• Optiwatt never pre-cools below your comfort range.
• If you change your thermostat during a pre-cool, Optiwatt hands control back to you. One exception: raising your cool setpoint during an event counts as working with the program, so it won't cancel the pre-cool.
• Once you cancel a pre-cool for an event, Optiwatt won't keep re-applying it.
• Canceling a pre-cool isn't the same as opting out of the event or leaving the program. Cancel a pre-cool and you're still in the event and still enrolled.

You don't need to do anything. Adjustments happen automatically, and you can always override your thermostat manually.