Demand Response for Smarter Home Cooling

From 4 to 9 p.m. on hot summer days, home cooling demand often rises just as the California grid comes under its greatest strain. Demand response for home cooling doesn’t have to mean accepting a warm house while a utility cycles your AC. It can also mean producing cooling before the peak period begins.

We work with Ice Cub systems that store energy as ice ahead of the evening peak, then use that stored cooling alongside a home’s existing HVAC system. This gives homeowners another way to approach demand response: plan cooling around when it matters most rather than simply use less.

How Demand Response Changes Home Cooling

Demand response is a reduction, increase, or shift in electricity use prompted by a price, program incentive, or grid reliability signal. For home cooling, it asks whether a household can reduce the electricity its system draws when demand is highest.

Utilities and grid operators use demand response to limit purchases of high-priced electricity, support grid reliability, reduce fossil fuel use, and accommodate renewable generation. A Flex Alert, for example, is a statewide request tied to expected high electricity demand. For homeowners, the practical question is how to make cooling less electricity-intensive during the peak period, whether or not an alert is in effect.

Peak demand matters because cooling systems often run hardest while outdoor temperatures remain high and households are arriving home, cooking, and using appliances. Moving part of that cooling load outside the peak window can support the grid while changing when a home uses electricity.

Demand Response Options for Home Cooling

Households can reduce demand in several ways. The central distinction is whether the system changes operation in real time or produces cooling earlier in the day.

Thermostat-Based Programs
PG&E’s Automated Response Technology program lets eligible customers enroll a smart thermostat through an authorized provider. When an event begins, a connected thermostat automatically shifts cooling use outside peak hours. Customers can opt out by changing the thermostat setpoint, retaining direct control when their comfort needs change.

Load-Control Switches
PG&E’s SmartAC load-control switch cycles a central AC compressor at a 50% duty cycle for the event. As of November 6, 2026, enrollment for SmartAC switches is closed to new customers. Existing participants should follow their program materials for event and opt-out details.

Precooling
Precooling lowers the home’s indoor temperature before the peak period so the cooling system can run less later. PG&E recommends precooling in the morning and setting the thermostat to 78 degrees or higher from 4 to 9 p.m. when health permits. Its effectiveness depends on how well the home retains that earlier cooling through the late afternoon and evening.

These options can reduce demand, but their results depend heavily on thermostat settings, insulation, and household routines. Thermal energy storage changes the timing of cooling production itself.

How Ice Storage Shifts Cooling Demand

Thermal energy storage stores cooling for later use rather than storing electricity in a battery. An ice storage system makes ice during off-peak hours and uses it during periods of higher demand.

Our Ice Cub works in parallel with existing HVAC equipment. It stores energy as ice before peak demand, then uses that ice to cool the home and reduce compressor runtime during the evening peak. Instead of relying entirely on a higher thermostat setting, the home can draw on cooling produced earlier.

This timing distinguishes ice storage from thermostat-based programs. A smart thermostat reduces or delays conventional cooling operation in response to an event, while storage moves part of the cooling load before the peak period begins.

The system doesn’t export electricity to the grid. For homes with solar energy, it can also pair with solar, storing excess daytime production as cooling for use later in the day.

Comfort, Control & Utility Program Rules

Comfort during demand response depends on the approach, weather, property, and household needs. PG&E states that SmartAC participants generally experience a one- to three-degree indoor temperature increase during SmartAC events. That change may be manageable for some households but unsuitable on certain days or for particular health needs.

Before evaluating a program, confirm which electric utility serves the property. PG&E serves Rocklin, including ZIP codes 95677 and 95765. Rocklin residents may purchase energy through Pioneer Community Energy, while PG&E continues to own the distribution lines.

Nearby Roseville has a separate utility and program. Roseville Electric Utility’s Power Flex program offers eligible residential and small-business customers a $25 enrollment credit plus $25 each year for allowing small thermostat adjustments during the 4 to 9 p.m. peak period. The program applies to Roseville Electric customers, not PG&E customers in Rocklin.

Program rules, payments, enrollment periods, and event terms change. Check the provider, rate structure, central air conditioning equipment, and opt-out process before enrolling. These details also help determine whether a thermostat program, precooling routine, or stored-cooling system suits the household.

Planning Your Peak Cooling Strategy

Start with when the home needs cooling most. Review recent utility bills, late-afternoon and evening thermostat habits, and whether solar production overlaps with cooling use. A household that needs substantial cooling after solar production falls will assess load shifting differently from one that’s lightly occupied during the evening peak.

Consider these questions when comparing demand response options:

• When does the cooling system run longest, particularly during the evening peak?
• How comfortable is the household with precooling or temporary thermostat changes?
• Does the home produce more solar power during the day than the household uses at that time?
• Would producing cooling earlier reduce reliance on the compressor later?

We review recent utility bills, current cooling habits, and solar or home-improvement plans to estimate how much cooling load could move off-peak. Ice Cub typically doesn’t require a separate utility interconnection agreement because it doesn’t export power to the grid, although standard mechanical and electrical permits still apply.

Changing thermostat behavior for an event and shifting cooling production in advance are different tools, and some homes may use both. To assess thermal energy storage, solar pairing, and peak-period cooling for your property, contact Ice Energy at (949) 334-2243.