Decision brief Bill analyzer
Energy · 134 Willow Ave

Base Power decision brief

Family decision brief on the Base Power whole-home battery offer for 134 Willow — plus a setup tracker for the house's utilities. Prepared September 26, 2026. Pricing and terms can change; the final agreements control.

Recommendation: proceed after closing — apply if the $95 Illinois offer is still available and the property qualifies. Treat $3,600 of savings as an upside case, not a promise, and confirm the final supply terms, site price, solar pathway, lender/title implications, and installation location in writing.
$95
Current Illinois installation price published by Base
39.2 kWh
Base Core storage capacity
Up to 36 hr
Advertised backup at reduced usage

How the economics work

Base owns and controls the battery. It earns money by operating a fleet of home batteries to support the grid. In exchange, we get low-cost backup and buy electricity supply from Base at published rates currently at least 25% below ComEd’s Price to Compare. ComEd still delivers the power and sends the bill.

Practical example: at 1,000 kWh, Base’s published 7.6–7.8¢ supply rates versus roughly 10.4¢ for ComEd imply about $26–$28 less on the supply portion, before taxes and other bill components. That is not 25% off the entire ComEd bill — delivery charges remain.

The money, without the sales gloss

$3,600 is valid math — but it is the optimistic 12-year case.

The $3,600 arithmetic

Monthly supply savings assumption
$25
12 years × 12 months
144 months
Gross projected savings
$3,600
Less the $95 promotional installation price
−$95
Net
$3,505

The catch: $25 for 144 straight months is an assumption. The published 25% comparison applies to electricity supply, not the entire ComEd bill, and the separate electricity agreement — not the 12-year battery agreement — governs how long a particular supply price lasts. The 25% discount is only guaranteed for the first 2-year supply term; after that Base promises to meet or beat ComEd’s price to compare by an amount set at renewal.

Conservative floor

If the 25% protection lasts only for the first two-year supply term, $25 a month produces $600 gross, or $505 after a $95 install. Later savings are unknown until renewal terms arrive.

Upside case

If $25 average savings continues for all 12 years, gross savings reach $3,600 and net savings are $3,505 after the $95 install. If ComEd’s price to compare keeps climbing (it rose from 9.66¢ to 10.399¢/kWh in June), dollar savings could grow — but only while the discount holds.

What “$95 total” really means

It is the published promotional charge for a standard installation (limited to the first 2,000 Illinois customers — $295 after that), with no ongoing battery fee advertised. It is not a cap on nonstandard site work, electricity charges, late/rescheduling fees, early cancellation ($500 if Base recovers the equipment), damage, or failure to surrender the battery.

The trade

The benefits are practical; the costs are mostly loss of control.

Reasons to do it

Very low cost for substantial backup

Base advertises the 39.2 kWh Core in Illinois for $95, with no monthly battery fee. Comparable backup normally requires a large capital purchase.

Automatic whole-home outage protection

Up to 36 hours at reduced consumption. Practically: prioritize heat controls, refrigeration, lights, internet, and the sump pump — not central A/C, dryer, oven, and EV charger as usual.

Lower electricity supply pricing

Published time-of-use supply rates at least 25% below ComEd’s Price to Compare (currently 7.8¢ on-peak, 7.6¢ off-peak).

Service and maintenance handled

Base owns the system and is responsible for maintenance, warranty support, repairs, and replacements.

No fuel, exhaust, or annual generator service

Quiet and automatic — no fuel logistics, emissions, or routine servicing of a standby generator.

Reasons to pause

A 12-year property commitment

Cancelling in year 5 normally means a $500 removal charge if Base recovers the equipment. Damage is charged at repair cost; blocking recovery can trigger fair-market-value damages.

Backup is not guaranteed

Base controls charging and dispatch and only endeavors to preserve at least 5 kWh. Keep a separate plan for medical equipment and long winter outages.

We do not own or operate the asset

Base controls when energy goes to the house, grid, or battery, and keeps the tax credits, rebates, demand-response payments, and other program value.

A sale requires coordination

Practical example: the contract calls for 90 days’ notice. For a June 30 closing, notify Base by about April 1 and have the approved buyer sign Base’s assignment form before closing — or the transfer can be treated as early termination.

One-sided paperwork

Base may record evidence of its ownership or make UCC filings. Disputes go to individual arbitration, generally in Austin, under Texas law; liability is limited.

Startup and counterparty risk

Twelve years is a long time for a young company. The agreement can be assigned to another service provider.

Future-proofing the choice

A roof or solar project in 5–7 years does not undo the case.

The battery is ground-mounted, so a normal reroof should not require removing equipment. Solar is technically compatible — Base says Core can connect to solar, and the Illinois battery agreement already requires a Net Metering Addendum. During an outage, solar may extend backup by recharging the battery.

The limitation is control: Base — not us — operates the battery and keeps grid-program compensation. A future solar installer will need to design around Base’s equipment and ComEd interconnection requirements. The contract requires 90 days’ notice for improvements that may affect the battery, so get Base’s written coordination requirements before any future roof, panel, service, or electrical project.

Interpretation: Base is a good low-cost resilience decision now, even if solar is likely later. It is less attractive only if owning and personally optimizing a solar battery is already a near-term priority.

Six confirmations before signing

  1. Final price and eligibilityConfirm $95 is still the complete standard-install price for 134 Willow and identify any nonstandard-site charges before work begins.
  2. Supply agreementRead the separate electricity contract; verify the initial term, on/off-peak periods, renewal formula, and every fee — not only the battery agreement.
  3. Backup expectationsAsk what minimum charge reserve Base targets before forecast storms and which major loads may need to be curtailed.
  4. Winter controlsAsk whether Core has active battery heating and whether Base curtails grid dispatch in extreme cold to preserve outage reserve and charging ability.
  5. Solar pathwayGet written confirmation that future rooftop solar can integrate, what equipment is compatible, and whether Base or the solar installer handles interconnection changes.
  6. House paperworkBecause the home will be trust-owned and mortgaged, confirm signatories and ask the lender/title team whether Base’s ownership notice or possible UCC filing requires consent or later release documentation.

At the end of the term

In 2038, renewal is opt-in — not automatic.

About 30 days before the renewal date, Base must provide notice and an opportunity to renew under the terms available at that time. To continue, we must notify Base in writing during that 30-day opt-in period — the new price, battery arrangement, and terms could differ from today’s deal. If we do nothing, the agreement ends; there is no automatic 12-year renewal. If service ends, Base may immediately render the battery inoperable, notify us in writing, coordinate a removal time, and remove the battery.

Practical example: suppose Base offers another 12-year agreement in 2038 for a newer battery and a modest supply discount. We compare that offer against buying our own storage, using a generator, or having no backup. We are free to decline; the key obligation is giving Base access to recover its equipment. One calendar item worth setting later: review the renewal notice as soon as it arrives — thirty days is a short window, and ignoring it means the battery agreement ends.

Winter performance

Base rates Core for operation from −22°F to 122°F, which covers normal Deerfield winter temperatures. But the ComEd rollout is new, and Base has not published Illinois-specific field results covering a full local winter.

Lithium iron phosphate (LFP) batteries can discharge in the cold, but usable capacity can temporarily fall by roughly 20–30% in subfreezing conditions. Charging cold cells below 32°F can cause permanent damage, so an outdoor system must rely on thermal management and a battery-management low-temperature cutoff. In a deep-cold outage, expect less runtime than a 12–18 hour real-world planning estimate; capacity recovers as the cells warm.

Decision rule

Say yes unless one of these issues changes the deal: the installed price stays near $95 with no material site charges; the supply terms match the pitch; the equipment location works for the property; future solar is confirmed in writing. Pause if: site costs materially increase, we expect to sell soon, owned solar storage is a near-term goal, or the lender/trust structure creates friction.

Bottom line: a qualified yes. The everyday downside is small relative to the value: low-cost backup plus supply savings. The meaningful catch is accepting a 12-year relationship in which Base owns and controls equipment attached to the property. If the confirmations are clean, proceed.

Download the PDF brief

Household utilities

Setup tracker for 134 Willow — placeholders until accounts are opened around closing. Nothing here is active yet.

To set up

Electric delivery — ComEd

Delivery account must be in our name at or before the October 15 closing. ComEd keeps delivering power and sending the bill no matter who supplies the electricity.

Deciding

Electricity supply — Base Power

The offer evaluated in this brief. Decision after closing; the October 16 calendar reminder covers the $95 price check. If we pass, supply stays with ComEd.

To set up

Natural gas — Nicor Gas

Nicor Gas serves most of the northern third of Illinois outside Chicago, so it is the expected provider for Deerfield — confirm when opening the account. Set up before move-in; the furnace is gas (Roberts Heating check November 3).

To set up

Water / sewer / garbage — Village of Deerfield Finance

Seller notifies Finance by October 8 for the final meter reading; we set up our account at or before closing. Trash day is Wednesday — confirm with the village at move-in.

To choose

Internet

Provider to be chosen before move-in. Placeholder for now.

Future

Rooftop solar

Revisit in roughly 5–7 years. See the future-proofing notes above for how it interacts with the Base battery.

Sources

Base Power — Illinois offer and rates (basepowercompany.com/illinois)
Base Power — Illinois Battery Services Agreement (PDF)
Base Power Help Center — moving or cancelling
Base Power — Core specifications
Canary Media — Illinois launch and business model
LFP cold-weather technical overviews
Prepared September 26, 2026 · energy.naginskyhome.com · Pricing and terms can change; the final agreements control.