Assumptions

The campus and its bill

Load

210 MW. "Less than 300 megawatts, more like 210", including cooling, from Fluidstack's engineers at the 28 Jul 2026 county board meeting. Appalachian Power has not published its figure.

Demand charge

$9.96 per kW-month, Schedule L.P.S. at transmission voltage (Tariff 28, effective 1 Jan 2025, unchanged in the Nov 2026 update). At 210 MW: $25.1M a year.

The billing floor

The model assumes the campus runs at full capacity, so each credited kW comes off the demand charge one for one. Under SCC order PUR-2025-00057 (1 Jun 2026) billing demand is never below 80% of contract capacity ($20.1M a year at 210 MW, on a 14-year contract); below it, the credit needs ask 3 on the case study.

Energy

0.386 cents per kWh base energy plus a 3.133 cent fuel factor (interim from 1 Nov 2025), at an assumed 85% load factor: $55M a year. Riders and taxes are left out, so the $80.1M total is low.

The credit

What the law says

Va. Code 56-596.7 (in force 1 Jul 2026): customers of 25 MW or more with a 75%+ load factor may fund or buy capacity reduction credits from other retail customers, directly or through third parties. Results must be measured and verifiable. The State Corporation Commission designs the incentives, may include faster interconnection, and must avoid shifting costs. It does not say the credit reduces a demand charge: that is what this study proposes.

Value

$120 per credited kW-year, the demand charge rounded ($119.52). Cross-check: PJM's 2027/28 capacity price, $333.44 per MW-day, is $121.70 per kW-year. The credit is a full year's value for kW that only shows in the December to February windows: PJM's capacity obligation is annual, and its loss-of-load risk is now mostly in winter.

Term and discount

14 years (the large-load contract term) at 7%: a dollar a year is worth 8.75 today.

Not yet decided

The credit's value, the baseline, how long an upgrade earns credit and how often it is re-checked, whether battery exports count, and whether efficiency stays eligible (Dominion's draft would limit eligibility to dispatchable capacity).

The homes

Program area and phases

Homes within 1 mile: 56; 3 miles: 734; 5 miles: 4,744; 10 miles: 10,268. 2020 Census blocks (housing units), by distance from the site. Phase 1 (the pilot) within 3 miles, Phase 2 out to 5; the budget reaches the closest homes first. The law reaches any Appalachian Power home in Virginia; the phases are where a program built for trust starts.

Sign-up and occupancy

50% of homes in the area sign up (an assumption). The counts are housing units, occupied or not; about 10% stand empty. Every unit is counted by default; at 90% occupancy Phase 1 has 330 homes instead of 367, and the budget still reaches 642.

County

13,990 homes (2020 Census), 76.6% owner-occupied (ACS 2019 to 2023). Electricity heats 66.4% of homes county-wide and 73% in the four block groups nearest the site (ACS 2020 to 2024).

The three kinds of home

From a check of Phase 1 on 3 Nov 2026: Census ACS 2020 to 2024 block groups within 3 miles (about 20% manufactured homes, half built before 1980, about 28% rented), VGIN building footprints (median roof area about 1,570 sq ft, 11% single-wide shapes) and a Street View sample. Site-built, one storey, 1,500 sq ft, built in the 1970s (50%); site-built, one storey, 1,500 sq ft, built in the 1980s or 1990s (32%); about 1,000 sq ft, ducts under the floor; roof cavity r-11, 2x4 walls, leaky (an assumption: the engine has no manufactured-home type) (18%). IECC 4A.

Who gets what: the cap

The sponsor sets a cap: pay for an upgrade when it costs at most $3,000 per verified peak kW in that home. Upgrades are tested in the order attic, heat pump, thermostat, each counted on top of the ones already in. A gas home draws no electric heat at the peak, so its upgrades cut nothing and it gets none; a new heat pump in a gas home would add load. A working heat pump is not replaced at this cap: replacing a 20-year-old unit costs about $7,000 per kW in the 1970s ranch, a newer one about $12,300. The battery is decided apart: every program home gets one, for backup, the bill and dispatch. Upgrade targets: attic R-38, heat pump SEER2 16 and HSPF2 8.8, a setback thermostat. Manufactured homes get no attic job (a roof cavity is a different, costlier job).

Prices are bulk prices with fixed-price installs, each an input until a written local quote: attic $1.65 per sq ft (retail $1.50 to $2.45, Home Depot 2026); thermostat $225; heat pump $9,000 ducted and $12,000 ductless for a baseboard home (50% of site-built resistance homes), against measured retail installs of $12k to $19k (TECH Clean California, NYSERDA) and group-buy savings of 10 to 20%.

The household bill

Each home's year is built hour by hour on the local typical year: heating from its envelope and equipment, other household use flat at its internal gains (0.82 kW in a site-built home), cooling from the engine's yearly cooling kWh spread over the hours above 65°F. The thermostat's setback trims heating 8% and cooling 10% (ENERGY STAR connected thermostat metrics, the engine's factors), and its preheat moves energy out of the winter peak windows. The year is priced on all four residential schedules (Appalachian Power Tariff 28, base rates), each kWh carrying the same 8.517 cents of fuel factor and riders (the 16.139 cent all-in price on R.S.: the $169.35 bill for 1,000 kWh less the $7.96 customer charge, less R.S.'s 7.622 cents). The saving counts the cheapest schedule today against the cheapest after, so switching schedules alone is not counted.

The battery through the year

Every weekday it covers the home's load in the evening window (5 to 8 pm) and, with what is left, the on-peak hours before it; on winter weekdays it also covers the morning window (6 to 9 am) and recharges 10 am to 2 pm. It charges overnight at 90% round trip. Under "exports count" it discharges its full window rate in the winter windows and exports what the home does not use.

Exports and making the household whole

The kW credit belongs to the program; exported kWh belong to the household, credited at the on-peak rate (14.306 cents) if the filing grants it. The household's floor is what the same battery would save it measured to zero: in any year the battery and its export credit come to less (exports not credited, or the winter morning window forcing an on-peak recharge), the program pays the difference, the make-whole. That payment is a program cost: with exports counted and not credited to the household, $98K a year for 642 homes, against $32K when they are credited. Both rules go in the host agreement.

The average program home

$2,270 a year today, $1,675 after: $562 from the upgrades and $33 from the battery. Most homes are already cheapest on the smart demand schedule, whose off-peak rate leaves a battery little to shift.

The winter peak, one home hour by hour

A home's peak kW is its average draw over the winter peak window, not one design hour: the morning (6 to 9 am) and evening (5 to 8 pm) hours of the ten coldest December to February days in the local typical year (Marion-Wytheville Mountain Empire AP, VA, TMY3), 60 hours averaging 15.4°F (coldest -2.2°F). Each hour's heating load is the home's heat loss at that temperature (for the 1970s ranch, 157 W per °F before the attic upgrade, 128 W after, less the internal gains, at 70°F inside).

New heat pump

A cold-climate model, COP 2.00 at 5°F (NEEP's specification asks at least 1.75), about 0.6 higher at 17°F and 1.6 higher at 47°F: COP 2.52 at the window's average.

Existing heat pump

A 10-year-old standard unit (HSPF2 7.5) with strip heat runs at COP about 3.0 at 47°F, 2.0 at 17°F and 1.4 at 5°F. Its gain over strip heat scales with its rating and fades 1.5% a year past 10 years (an assumption; field studies report 1 to 2%), so at the window's average the older unit runs at COP 1.68 and the newer at 1.99.

Preheat

The smart thermostat warms the home before each peak window, moving 25% of the heating draw out of it into the two hours before (energy moved, not saved). Conservative next to field trials (a UK trial of three homes cut heat pump draw 56 to 90% over a 3-hour peak at 41°F).

The battery

Capacity and price

Sized in 13.5 kWh steps (13.5, 27.0, 40.5 kWh) on one 11.5 kW inverter, a Powerwall 3 class unit with expansion packs. The first 13.5 kWh $12,000 installed at bulk (Wythe retail about $17,550, EnergySage, Oct 2026), each further 13.5 kWh $6,000: $12,000, $18,000, $24,000. Expansion packs share the inverter, wiring and crew; a Powerwall 3 expansion lists at about $5,900 before install (about $6,200 installed), a FranklinWH aPower adds about $11,000 plus $800 to $1,000 to install, HomeGrid modules retail about $760 per kWh (checked 3 Nov 2026).

kW at peak: two rules

Usable energy sits above a 20% backup reserve, spread over the 3-hour window: 3.6 kW for 13.5 kWh, 7.2 kW for 27.0 kWh, 10.8 kW for 40.5 kWh, never above the inverter. Measured to zero (the base case), the battery is credited only for the home's own load, hour by hour: 2.42 kW across the program. Exports count (the filing's ask): the full window rate.

Tax credit

The program owns the batteries, so each may earn the 30% clean electricity investment credit (section 48E, energy storage). Subject to tax review: storage that begins construction after 2025 loses the credit if it takes material assistance from a prohibited foreign entity, which depends on the battery's supply chain. The upgrades belong to the homes and earn no business credit; the homeowner credits (25C, 25D) ended after 2025.

The program

Structure

A separate entity (the Community Bill Reducer), funded by Fluidstack, owns and runs the batteries and pays for the upgrades. The law allows credits bought through third parties. Installers work on fixed-price contracts drawn from Appalachian Power's participating contractor list and the county's. Households apply for nothing and pay nothing.

No utility rebates

Appalachian Power counts the savings from its own rebated measures. Using them would leave the kW claimed twice, so the program pays in full, and a home that already took a rebate for a measure is not credited again for it.

Upkeep

$150 per program home a year ($100 to $200 is the range): battery monitoring and warranty service, dispatch and measurement. $96,300 a year for 642 homes, $842,189 over 14 years at 7%. It is in the net cost, not the budget: the budget pays installs only.

Not included

Battery replacement after the term, enrollment marketing, financing, and any value beyond the demand charge. Faster interconnection is not claimed.

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