Utility program deep dive · Illinois

ComEd residential battery, solar and VPP economics

What ComEd’s $300 rebates, scheduled-dispatch VPP and rate plans are worth to Northern Illinois households: rate pathways, a capital stack by package, paybacks and what could change.

VPP Economics has no affiliation with, sponsorship from, or endorsement by any utility, aggregator, platform, or device maker named here.

The short answer

  • The $300 rebate is the largest single incentive for a home battery. ComEd pays $300 per kWh to residential customers, $4,050 on a 13.5 kWh battery, including batteries without solar from January 1, 2027 (ComEd Rider DG Rebate). In return, the battery must join the Scheduled Dispatch VPP for five summers and discharge 4–6 p.m. on weekdays. That program pays $10 per kW-season, about $50 a year (Rider SDVPP).
  • The rate plan decides the rest. On ComEd’s default fixed price, a battery has almost nothing to shift. On Time-of-Day Pricing, a peak kWh costs about three times an overnight kWh (Certasun), worth roughly $623 a year to one battery. On Hourly Pricing, the household pays its own capacity charge, which a battery can cut.
  • Battery-only paybacks are long; solar changes the picture. At Illinois average prices, a battery on Time-of-Day takes about 19 years to repay its net cost, before backup value. An 8 kW solar array with the $300/kW rebate and Illinois Shines REC payments pays back in about 6 years if the installer passes the REC value through.
  • Hosting a battery can beat owning one. Base Power installs a company-owned 40 kWh battery for $295 ($95 for the first 2,000 members) and sells supply at least 25% below ComEd’s price to compare for two years (Base Power). For a home using 8,000 kWh a year, that is about $202 a year and a payback near 1.5 years, with three times the backup energy of a 13.5 kWh battery the household owns.
  • Details are still coming. The participant agreement and program administrator for the Scheduled Dispatch VPP had not been published at the time of writing. They are expected with the January 2027 application opening and the spring 2027 launch.
$300/kWhbattery rebate, homes
$300/kWsolar rebate, homes
$10/kWper season, scheduled dispatch
~3×TOD peak vs overnight price

What each ComEd program is

Upfront incentive

Storage and solar rebates

$300 per kWh of battery capacity and $300 per kW DC of solar for residential and under-100 kW customers through 2029; $250 from 2030 for stand-alone storage (Rider DG Rebate, Illinois Power Agency). The battery rebate is capped at 5 kWh per kW of battery power, which standard home batteries meet.

Scheduled dispatch

Scheduled Dispatch VPP

Required for rebated batteries. Discharge 4–6 p.m. Central time every weekday, June 1 to September 30, for five seasons. Pay is average kW across all window hours × $10. Pay can be assigned to a third-party owner (Rider SDVPP). It is one-way and scheduled, not orchestrated.

Behavioral DR

Peak Time Savings

Typically three to five summer events; $1 per kWh reduced below the home’s baseline. ComEd estimates $1 to $12 per event (ComEd).

Device DR

Central AC Cycling

$5 or $10 a month from June to September, $20 or $40 a season, for letting ComEd cycle the compressor (Citizens Utility Board). It cannot be combined with Peak Time Savings (Phantom Grid, citing the tariff).

Price signal

Time-of-Day Pricing

Four fixed periods every day; the 1–7 p.m. Mid-Day Peak is the most expensive. Registered EVs earn $2 a month for up to 24 months (ComEd).

Price signal

Hourly Pricing and Delivery Time-of-Day

Hourly Pricing bills supply at real-time PJM prices plus a separate capacity charge set by the home’s load in last summer’s 10 peak hours (ComEd). Delivery Time-of-Day changes only delivery and can be paired with the fixed rate or Hourly Pricing (Certasun).

Rate pathways for one battery

Annual value by rate pathway

One 13.5 kWh, 5 kW battery, stacked by source. Gross bill effects plus program pay.

Swipe to see the full chart →

$0$200$400$600$800$1,000$1,200$1,400Fixed rate (default)flat price · VPP only$50Fixed rate + Delivery Time-of-Daydelivery shift only$262Time-of-Day Pricingsupply + delivery shift$673Hourly Pricing + Delivery TODcapacity + hourly + delivery$688Time-of-Day + future VPP (what-if)$100/kW-yr customer share$1,173Time shiftCapacity cutHourly arbitrageScheduled VPPFuture VPP
Illustrative. All-in marginal prices from Certasun (October 2026): Time-of-Day 32.9¢ peak and 10.7¢ overnight in summer, 31.2¢ and 11.4¢ otherwise; fixed rate with Delivery Time-of-Day 24.7¢ and 16.2¢. Assumes 12 kWh discharged in the 1–7 p.m. peak in summer and 7 kWh otherwise, at 90% round-trip efficiency. Capacity: 2.5 kW off the household PLC at ComEd’s $10.11 per kW-month rate and factors (Citizens Utility Board). Hourly arbitrage of $150 a year is an assumption. Future VPP is a what-if.

Time-of-Day Pricing is the simplest pathway. The battery charges overnight and covers the 1–7 p.m. peak, earning about $623 a year by our estimate. The 4–6 p.m. VPP window falls inside that peak, so the scheduled dispatch obligation costs the household nothing extra.

Hourly Pricing exposes the capacity charge. ComEd sets each Hourly Pricing customer’s capacity obligation from its load in the five PJM and five ComEd summer peak hours, which have historically fallen between 3 and 7 p.m. on the hottest weekdays (ComEd). A single-family home without electric heat averages about 3 kW (ComEd). Cutting 2.5 kW saves about $276 a year, starting the following June. The scheduled 4–6 p.m. discharge already covers most of those hours.

On the default fixed rate, every kWh costs the same, so the battery earns only the $50 VPP payment and its backup value. Peak Time Savings could add a few dollars per event, but ComEd may reduce VPP credit for hours paid under another program.

The capital stack

Ten-year capital stack by package

Incentives plus 10 years of bill savings and program pay, as a share of installed cost. Past the dashed line, the package more than covers its cost.

Swipe to see the full chart →

0%50%100%150%200%Solar 8 kW DCrebate + RECs + bill126% · $30,220 vs $24,000Solar + battery, Time-of-Dayboth rebates + RECs101% · $41,000 vs $40,740Battery, Tesla price, Time-of-Day13.5 kWh at $967/kWh83% · $10,780 vs $13,050Battery, Hourly + Delivery TOD13.5 kWh at $1,240/kWh65% · $10,930 vs $16,740Battery, Time-of-Day13.5 kWh at $1,240/kWh64% · $10,780 vs $16,740Battery, fixed raterebate + VPP only27% · $4,550 vs $16,740Covers full costComEd rebatesIllinois Shines RECsSolar bill value / hourly arbitrageTime-shift savingsCapacity charge cutScheduled dispatch VPP
Illustrative, undiscounted. Battery at $1,240 per kWh (EnergySage Illinois average) or Tesla’s $967 (EnergySage). Solar at an assumed $3.00 per watt, 1,200 kWh per kW DC, 40% used on site at 19.2¢ and 60% exported at the 10.3¢ supply credit (Certasun). RECs at the Group B 0–10 kW price of $80.77 plus a $20 adder for customer-owned systems that do not take a federal credit (Illinois Shines, Illinois Shines). No federal credit for homeowner-owned systems (Solar Cost Data).

For solar, the Illinois Shines REC contract is the largest layer, about $14,511 on 8 kW. Small systems approved from June 1, 2026 receive 50% at energization and the rest over six years (Illinois Shines). The payment goes to the installer (the Approved Vendor), and how much reaches the household depends on the installation contract (Illinois Shines).

A battery alone covers about 60–80% of its cost over 10 years on today’s rates. The rest has to come from backup value, a lower price or the future VPP. Paired with solar, the combined package roughly breaks even within 10 years.

Simple payback by package

Years to repay net cost from bill savings and program pay, before backup value.

Swipe to see the full chart →

0 yr4 yr8 yr12 yr16 yr20 yrHosted battery, Base Power$295 install, 25% off supply1.5 yrSolar only, 8 kW DCfull REC pass-through5.6 yrSolar + battery, Time-of-Dayboth rebates + RECs9.9 yrBattery, TOD + future VPPwhat-if: +$500 a year10.8 yrBattery, Tesla price, TODnet $9,00413.4 yrBattery, Hourly + Delivery TODnet $12,69018.4 yrBattery, Time-of-Daynet $12,69018.9 yr
Same assumptions as the capital stack. Solar paybacks assume the full REC payment reaches the household. Fixed-rate batteries do not pay back on bill value and are omitted. The hosted battery assumes a 25% supply discount on 8,000 kWh a year.

Assets and combinations

Smart thermostat or AC

AC Cycling or Peak Time Savings

AC Cycling pays $20–$40 a season with little effort. Peak Time Savings pays per kWh reduced and suits households that will act on event days. Choose one.

+
EV

Time-of-Day for overnight charging

Charging overnight at about 10.7¢ instead of 19.2¢ saves roughly $300 a year on 3,500 kWh, plus the $2 monthly EV registration credit for up to 24 months (ComEd, Certasun). An EV is not eligible for the storage rebate (Rider DG Rebate).

One battery, 13.5 kWh

5 kW paid · 2-hour window

$4,050 rebate, $50 a year of VPP pay. On Time-of-Day, the 1–7 p.m. peak uses the energy the 2-hour VPP window leaves unpaid.

Solar only

The strongest case on paper

$300/kW rebate plus RECs. New net-metering customers since 2025 receive export credits on supply only (ComEd), so self-use and storage matter more than they used to.

+
Solar + battery

Store exports for the peak

Each kWh stored instead of exported earns the peak retail price rather than the supply credit. The battery can charge from solar and still meet the 4–6 p.m. obligation.

++
Battery + EV + thermostat

One household, three programs

Time-of-Day supports both the battery and overnight EV charging. AC Cycling adds a small fixed credit. Stacking them on one rate avoids conflicting price signals.

Behaviors each program needs

Battery

Charged by 4 p.m. on summer weekdays

Pay follows average output across every scheduled hour, so an empty or offline battery counts as 0 kW for that window. Backup reserve settings compete with dispatch.

Hourly Pricing

Watch the 10 peak hours

The capacity saving depends on discharging during the specific PJM and ComEd peak hours, known only after the summer. Covering 3–7 p.m. on the hottest weekdays is the practical rule.

Time-of-Day

Move load out of 1–7 p.m.

The Mid-Day Peak price applies every day of the year, so the battery or the household has to cover it in winter too.

Financing: buy, borrow, lease or host

Three ways to pay for one battery

One 13.5 kWh battery on ComEd Time-of-Day Pricing, with the storage rebate and the scheduled-dispatch VPP. Money in and out of the household, then cumulative cash over 10 years.

Swipe to see the full chart →

OWN IT OUTRIGHTCash−$16,740 to the installerday one+$4,050 storage rebate$300 per kWh × 13.5 kWh+$50 a year for 5 yearsScheduled dispatch VPP+About $623 a yearTime-of-Day bill savings=Household owns the batteryand its backup value10-year net cash−$6,210Needs cash on day one$BORROW THE NET COSTLoan=$0 down; incentive pays principalborrows $12,690−$154 a month for 10 years8% interest+$50 a year for 5 yearsScheduled dispatch VPP+About $623 a yearTime-of-Day bill savings−$5,800 of interestover the loan term10-year net cash−$11,996Highest total costTHIRD-PARTY OWNERLease=$0 downowner buys the battery−About $97 a month for 10 yearsillustrative lease price=Owner keeps $5,020 credit30% commercial §48E=Owner keeps the $4,050 incentiveand scheduled dispatch VPP+About $623 a yearTime-of-Day bill savings10-year net cash−$5,426Credit lowers the priceCumulative cash to the household, years 0–10−$16,000−$12,000−$8,000−$4,000$0yr 0yr 2yr 4yr 6yr 8yr 10Leaseowner keeps the batteryCashowns the batteryLoanowns the batteryCash pays $12,690 on day one, after the incentive$5,800 of loan interest
Illustrative. Battery at $1,240 per kWh, the Illinois average (EnergySage). VPP pay counted for its five-year term (Rider SDVPP). Loan at 8% over 10 years on cost after the rebate. Lease price assumes the owner claims the 30% federal credit (Solar.com), the rebate and the VPP pay, and recovers the rest at 8% over 10 years; real offers vary. Hosted batteries are compared in the next section. Excludes backup value, degradation and taxes.
Cash

Keeps the rebate and the asset

Net cost about $12,690 at Illinois average prices, or $9,004 at Tesla’s. Homeowners get no federal credit for systems placed in service after 2025 (Solar Cost Data).

Loan

Payments exceed savings

At 8% over 10 years on $12,690, payments run about $154 a month, against roughly $55 a month of Time-of-Day savings.

Lease or third-party ownership

Federal credit through the owner

A third-party owner can still claim the commercial §48E credit (Solar.com), and Rider SDVPP lets VPP pay go to the project owner (Rider SDVPP). The contract decides who keeps the rebate.

Hosted battery

Base Power and Energywell in ComEd

Base Power installs a company-owned battery for $95 to $295 and sells supply at least 25% below ComEd’s default rate under a 12-year agreement (Base Power, Chicago Tribune). The host, not the household, captures the grid value; see the comparison below and the Battery Economics hosted-battery case study.

Own or host: the Base Power example

Base Power launched in Illinois on June 24, 2026 as a licensed retail electric supplier, Base Retail LLC (Base Power). It installs a 40 kWh battery that it keeps owning, with up to about two days of whole-home backup, for a $295 installation fee, or $95 for the first 2,000 members, and no monthly battery charge. The household switches its supply to Base, at least 25% below ComEd’s default supply price for two years and then at or below the price to compare, under a 12-year agreement with a $500 early termination fee. Municipal permitting limits it to about a third of the ComEd market for now (Chicago Tribune).

Own or host

Ten years of household cash: buying a 13.5 kWh battery with the ComEd rebate, versus hosting a 40 kWh Base Power battery.

Swipe to see the full chart →

–$8,000–$6,000–$4,000–$2,000$0$2,000$4,000Own, Time-of-Day$16,740 battery, rebate, VPP–$6,210Own, Tesla price, Time-of-Day$13,054 battery, rebate, VPP–$2,520Own, Hourly + Delivery TODcapacity cut + arbitrage–$6,060Host, Base Power, discount 2 yearsthen meets the price to compare+$109Host, Base Power, discount 10 yearsif 25% holds the whole time+$1,720
Illustrative, undiscounted. Owned batteries net of the $300 per kWh rebate, with five years of Scheduled Dispatch VPP pay and the rate-plan savings above. Base Power at the $295 standard fee and a 25% discount on 8,000 kWh a year at ComEd’s 10.103¢ price to compare from October 1, 2026; the bottom bar assumes the discount holds, which Base does not guarantee after year two. The hosted battery offers 40 kWh of backup against 13.5 kWh owned. Excludes backup value and the early termination fee.

Hosting comes out ahead mainly because of who owns the battery under ComEd’s rules and PJM’s prices. This is our reading of the business model, not Base’s published economics. As the owner, Base can claim the commercial §48E credit that homeowners lost after 2025 (Solar Cost Data). As the household’s supplier, it carries the capacity and transmission obligations set by each customer’s peak load contribution, and PJM capacity cleared at the $333.44 per MW-day cap for 2027/28 (PJM), so a fleet that discharges in the summer peak hours cuts a large cost. It can also buy energy in cheap hours and serve customers in expensive ones, and may qualify for the $300 per kWh storage rebate. A household that owns its battery can reach only part of that, through Hourly Pricing.

The trade-offs are real. The household gives up ownership and the battery’s controls, commits to 12 years with a $500 exit fee, and has a guaranteed discount only for the first two years. A home that moves loses the arrangement unless the next owner signs on. Where Base is available, though, a household can get more backup for a few hundred dollars than it could buy for about $12,700 after the rebate.

What ifs

Future VPP

A performance program by 2028

Illinois law requires a broader VPP tariff with five-year rate locks, eligible thermostats, EVs and solar paired with storage, and pay tied to capacity, transmission and arbitrage value (220 ILCS 5/16-107.9). At $100 per kW-year to the customer, a 5 kW battery would earn about $500 more a year.

Rebate step-down

Waiting costs $675

Stand-alone storage drops to $250 per kWh in 2030 (Rider DG Rebate). On 13.5 kWh, that is $675 less.

Rate resets

Time-of-Day prices change each June

Summer prices are set for one year at a time (Certasun). A narrower peak-to-overnight spread would shrink the main savings layer.

Capacity

PJM prices stay high, for now

PJM capacity cleared at the $333.44 per MW-day cap for 2027/28 (PJM). That supports the Hourly Pricing capacity saving through at least mid-2028.

REC prices

2027–28 prices due early 2027

Illinois Shines sets REC prices each program year, so the solar layer can move.

Hosts and rebates

Who claims the rebate

If hosted-battery companies claim the $300 rebate on company-owned batteries, that lowers their cost; the tariff does not limit rebates to customer-owned systems.

Compare: ComEd DG Rebate for C&I for businesses, Ameren Illinois for the same rebate in MISO, and Con Edison residential for an event-based battery program at $100 per kW.

Method and caveats

An independent, hypothetical analysis for homeowners, renters, program managers, installers and other readers. Terms come from ComEd’s Rider DG Rebate and Rider SDVPP and related ComEd, Illinois Power Agency and Illinois Shines sources, checked October 26, 2026 (ComEd filing index).

Assumptions: 13.5 kWh / 5 kW battery at $1,240 per kWh or $967 per kWh; 12 kWh shifted on summer days and 7 kWh otherwise at 90% round trip; 2.5 kW capacity reduction on Hourly Pricing; $150 a year of hourly arbitrage; 8 kW DC solar at $3.00 per watt producing 9.6 MWh a year, 40% used on site; RECs at $100.77 including the customer-owned adder; full REC pass-through.

Figures are gross bill effects and incentives before financing, degradation, maintenance and taxes. Rate combinations and program overlaps (for example, Peak Time Savings with the VPP) should be confirmed with ComEd.

VPP Economics has no affiliation with, sponsorship from, or endorsement by ComEd, Exelon, PJM, Illinois Shines, Base Power, Energywell, Tesla or any company named here.

Keep going