Utility pitch

How the rules work

Program size

Batteries = MW x 1,000 / 20, rounded up. Storage MWh = batteries x 39.2 / 1,000. Share of homes = batteries / residential customers. The 20 kW and 39.2 kWh figures are Base's published spec for its home battery.

Program MW is nameplate. Next to it the pitch shows a capacity illustration that fits the utility's market, labeled as an assumption. Each starts the same way: hold back 20% of each battery for the home (or your own reserve) and count each battery at the power it can hold for 2 hours (about 15.7 kW).

• In a capacity market (PJM, MISO, ISO-NE, NYISO): an illustrative accredited MW, applying NYISO's final 2026-2027 capacity accreditation factor for its 2-Hour Energy Duration Limited class, 64.65% (Rest of State). For 100 MW nameplate that is about 51 MW. PJM has no 2-hour class; its 4-hour storage class is rated 59% for the 2028/2029 auction. A utility's own market may count home batteries differently.
• In ERCOT, an energy-only market with no capacity accreditation: no accreditation factor. The pitch shows the MW the fleet could hold through a 2-hour peak, because being available in the peak hours (the four summer coincident peaks, 4CP, and price spikes) is what a peak kW is worth there. For 100 MW nameplate that is about 78 MW.
• Elsewhere (CAISO, SPP, or no ISO): there is no centralized capacity market, so the pitch shows the same 2-hour peak MW and leaves accreditation as a question for the utility's own planning rules.

Percentiles

Each signal is compared with every utility in the file that publishes it. "Higher than 80% of US utilities" means 80% of those utilities report a lower value. Missing values are shown as "not published" and are never treated as zero.

Headline

The headline uses the utility's strongest public signal: whichever of outage minutes (SAIDI), outage count (SAIFI), storm risk, heat-wave risk, or demand-response enrollment has the highest national percentile. Ties go in that order.

Offer

0. If state law sets a utility program for home batteries, the pitch is to enroll in it. Illinois Public Act 104-0458 (SB 25, signed 8 January 2026, effective 1 June 2026) added 220 ILCS 5/16-107.9: ComEd and Ameren Illinois (utilities with more than 300,000 customers) must file a virtual power plant tariff by 31 December 2027, for approval by 31 December 2028. Homes with batteries enroll through aggregators; services include cutting the utility's capacity and transmission obligations. So ComEd and Ameren Illinois are ranked and pitched as Bulk peaking capacity through that tariff. ComEd's energy for default customers is bought through Illinois Power Agency procurements, and it buys their capacity itself in PJM's auction. The law's separate storage procurement (20 ILCS 3855/1-75(d-20)) is for stand-alone, utility-scale storage, not home batteries. Otherwise, if the utility is wires-only, it delivers power but does not buy it, so there is no capacity offer. The pitch says so up top and points the talk at interconnection and Distribution grid support (or Speed to power if you mark a large-load queue). Wires-only means either: EIA-861 2025 counts 99% or more of its homes as buying energy from a retail provider (the Texas competitive area, where state law unbundled generation, retail and delivery), or it is a Pennsylvania investor-owned utility with retail choice (PECO, PPL, Duquesne, FirstEnergy Pennsylvania), whose default supply is bought under a state procurement plan. Pennsylvania has no law yet giving utilities a home-battery or virtual power plant program: House Bill 2264 passed the House on 16 June 2026 and sits in a Senate committee. Oncor, CenterPoint, AEP Texas and TNMP are also on a named fallback list. In these areas a home-battery company reaches homes as a retail provider.
1. If you mark that large loads are waiting to connect: Speed to power. No public file says this, so it is your input.
2. Else, if outage minutes or outage count is higher than 75% of US utilities: Distribution grid support. The 75% cutoff is an assumption.
3. Else, if at least half of residential customers sit in an ISO or RTO balancing authority: Bulk peaking capacity. In ERCOT, which runs an energy-only market, the fit is peak shaving: for a co-op or city utility, mostly its 4CP transmission cost allocation and peak wholesale energy. Elsewhere it is accredited capacity.
4. Else: Bulk peaking capacity, as peak shaving to reduce the capacity the utility must plan for.

Who to call first

Score = residential customers x SAIDI minutes. That is a residential stand-in for customer minutes interrupted, the total outage time a utility's homes sit through in a year. It favors big utilities with long outages. SAIDI covers all customers, so the product is an approximation. Utilities with no published SAIDI go last. Wires-only utilities are not ranked; they are named under the table.

Market first. A program's value case is built on one market's rules (capacity accreditation, peak pricing, transmission cost allocation). When one ISO or RTO holds at least 80% of a state's residential customers, utilities in it are ranked first and the rest follow, labeled "Outside" that market. In Texas that market is ERCOT (88% of homes in this file): Entergy Texas (MISO), Southwestern Public Service and SWEPCO (SPP) and El Paso Electric (no ISO) sit under different market rules, so they come after every ERCOT utility. In a split state, everyone is ranked together and each row names its market.

Utilities that already run a program with Base are never ranked as a cold call. They are listed after the ranking, labeled Already a Base partner (El Paso Electric: Runs a pilot with Base, as its own news release describes it), and their pitch is framed as expanding the existing program, with questions about what that program has shown. Checked on 4 November 2026, each with a public source: CoServ and Austin Energy (named on Base's Utilities page), Bandera Electric Cooperative (March 2025), Farmers Electric Cooperative (December 2025), El Paso Electric (a pilot, February 2026) and Guadalupe Valley Electric Cooperative (April 2026) in Texas, and Central Georgia EMC (October 2026). Base's own Utilities page reports "3 metro areas, 6 utility partners" over the last 12 months. EIA adjustment rows (state totals no utility reported) are left out.