Quick answer
ComEd and Ameren Illinois pay a one-time storage rebate of about $300 per kWh of battery capacity, around $4,050 for a 13.5 kWh battery. To qualify you generally must enroll in your utility's hourly or time-based pricing for the life of the battery. A battery pays off best if you'd otherwise export a lot of solar, want backup power or are on a time-of-use rate.
How much is the Illinois battery storage rebate?
ComEd and Ameren Illinois both offer residential customers a storage rebate of about $300 per kWh of the battery's nameplate capacity, alongside the $300/kW solar rebate. A 10 kWh battery works out to about $3,000 and a 13.5 kWh battery about $4,050.
The application is usually filed after the system is installed and the utility grants permission to operate. Your installer typically handles it.
| Battery capacity | Estimated rebate | Typical use |
|---|---|---|
| 5 kWh | $1,500 | Evening lights, fridge and internet |
| 10 kWh | $3,000 | Most evening use for a typical home |
| 13.5 kWh | $4,050 | A common single home battery size |
| 20 kWh | $6,000 | Larger homes, EV charging or longer backup |
What do I need to qualify for the battery rebate?
- A time-based rate. You generally must enroll in ComEd's or Ameren's hourly pricing or another time-based or peak-time program, and stay on it for the life of the battery.
- Program terms. The utility can call on the battery's capacity during peak periods under the program rules.
- Solar pairing. Sources disagree on whether a battery without solar qualifies under current rules, and a 2026 state law created a separate storage incentive, so confirm current terms with your utility or installer.
Is a solar battery worth it in Illinois?
Under the post-2025 rules, power you export earns roughly the supply rate, about 10.1¢ per kWh with ComEd for October 2026–May 2027, while power you use yourself saves the full rate of around 15–20¢. A battery lets you store midday solar and use it in the evening, capturing the higher value.
- Worth a close look: you're away during the day, you have an EV charged at night, you're on hourly pricing, or outages are a concern.
- Less compelling: your home uses most of its solar as it's produced, or you're not willing to move to a time-based rate.
Ask installers to show savings with and without a battery under supply-rate export credits, so you can compare the payback of each.
Will a battery keep my power on during an outage?
Only if it's set up for backup. Grid-tied solar alone shuts off during an outage for safety. A battery with the right inverter and a backup panel can keep chosen circuits, such as the refrigerator, lights, internet and a sump pump, running. Whole-home backup takes more capacity and costs more.
Sources
This guide is general information, not tax, legal or financial advice. Incentive programs change, so confirm current terms with your installer, your utility and a tax professional.