Which utility serves a charging site in Idaho?

Idaho Power serves the Treasure Valley (Boise, Meridian, Nampa), Twin Falls, and Pocatello; Rocky Mountain Power serves the southeast corner including Preston and Montpelier. Idaho Falls operates a municipal utility the model does not cover, the Rexburg area is rural-cooperative territory, and far-north Idaho around Coeur d'Alene is served by Avista and the Kootenai co-op — the model states territory limits rather than guessing.

Does Idaho tax EV charging per kWh?

No per-kWh charging tax exists in Idaho — EV fees are registration-side ($140 per year for a battery-electric vehicle). The model's energy-excise line is zero for Idaho sites.

How is the demand charge structured on Idaho Power's Schedule 19?

Three filed components: a seasonal base charge on the monthly all-hours peak, a basic charge billed on the trailing twelve-month demand, and a summer-evening component on a 7–11 p.m. window. For a site that draws its full hardware peak daily, each component resolves to the same monthly peak, and the model prices the sum — about $17.27 per kW bundled — exactly, overstating only where that assumption bends.

ForgeAsset / Supercharger ROI / Idaho

Tesla Supercharger ROI in Idaho

Idaho runs on some of the cheapest commercial electricity in the covered set — Idaho Power's bundled energy lands near six cents — under two different rate books: Idaho Power's Schedule 19 across the Treasure Valley, Twin Falls, and Pocatello, and Rocky Mountain Power's Schedule 6 in the state's east. No charging tax exists, the LLC annual report files free, and the tax stack is among the lightest researched.

Model a Idaho site

What makes Idaho economics distinct

Six-cent energy under a fresh rate order

Idaho Power's Schedule 19 carries bundled time-of-use energy of roughly 5 to 6 cents per kWh on settlement compliance rates effective January 2026 — among the cheapest in the covered set. The demand stack sums to about $17.27 per kW, with each component mapping onto structures the model prices exactly for a site with a steady billed peak.

Two books, one state

Boise, Meridian, Nampa, Twin Falls, and Pocatello are Idaho Power territory; the southeast corner — Preston, Montpelier, and the Bear Lake corridors — is Rocky Mountain Power's, at a flat 6.5-cent energy rate and about $15.36 per kW with no ratchet and no time window. Idaho Falls runs its own municipal utility and the Rexburg area is served by a rural cooperative — addresses there see a named-utility notice rather than a wrong auto-selection.

A tax stack that rounds to zero

Idaho's LLC annual report files free online, no franchise or net-worth tax reaches a pass-through LLC, and no per-kWh charging tax exists. Business personal property is taxed only above a $250,000 per-taxpayer county exemption, at about 0.65% in urban Ada County — a fraction of the multi-percent rates the heaviest covered states levy.

The power-cost adjustment is the moving part

Idaho Power's rates move through an annual power-cost adjustment that resets each June 1 — the current factor adds about half a cent per kWh and expires mid-2027. The model carries the in-force factor and the library re-derives it at each reset, so the modeled rate tracks the billed rate.

Utilities and tariffs modeled in Idaho

Utility & tariff	Energy	Demand
Idaho Power Schedule 19The filed rate book for this territory records no EV-specific commercial rate, so the modeled cost is the standard schedule. Demand follows the model's conservative convention — 150 kW per stall billed every month, the worst-case coincident peak — so a site whose metered peak runs below that would see a lower demand line.	5.0¢/kWh–6.1¢/kWh by time of day	$17.27/kW of monthly peak
Rocky Mountain Power Sch 6	6.5¢/kWh flat	$15.36/kW of monthly peak

Rates are digit-verified against each utility's own filed sheets and update within two weeks of any revision. Full derivations are on the methodology page.

See Idaho in the US Supercharger Economics Map — every US Supercharger over utility territories colored by the derived effective electricity cost per dispensed kWh.

Idaho tax profile

Sales tax on hardware: 6%
Business personal property tax: 0.65% of equipment value (example rate)
Clean-fuels credit: no program
Per-kWh charging excise: none

Idaho tax defaults applied: no clean-fuels credit program exists in Idaho (the LCFS revenue line is $0), LLC costs are $0 (the annual report files free online), and sales tax is the 6% state rate — covered metros levy no local addition. Business personal property is taxed at the Ada County urban rate of about 0.65% per year above a $250,000 per-taxpayer exemption; the field is editable and the exemption reduces the effective burden. No per-kWh charging tax exists in Idaho.

Idaho programs and incentives

NEVI (federal, ITD-administered)

Roughly $30 million over five years for corridor DC fast charging; the Idaho Transportation Department administers rounds along I-84, I-15, and I-90.

Idaho charging market

Idaho carries roughly 17 Supercharger stations, concentrated along I-84 through the Treasure Valley and Magic Valley with I-15 service through Pocatello and Idaho Falls. Boise's growth rate has ranked among the fastest of mid-size U.S. metros, and the corridor position between Salt Lake City, Portland, and Yellowstone-bound traffic shapes through-travel demand.

Idaho Supercharger ROI — questions

Which utility serves a charging site in Idaho?: Idaho Power serves the Treasure Valley (Boise, Meridian, Nampa), Twin Falls, and Pocatello; Rocky Mountain Power serves the southeast corner including Preston and Montpelier. Idaho Falls operates a municipal utility the model does not cover, the Rexburg area is rural-cooperative territory, and far-north Idaho around Coeur d'Alene is served by Avista and the Kootenai co-op — the model states territory limits rather than guessing.
Does Idaho tax EV charging per kWh?: No per-kWh charging tax exists in Idaho — EV fees are registration-side ($140 per year for a battery-electric vehicle). The model's energy-excise line is zero for Idaho sites.
How is the demand charge structured on Idaho Power's Schedule 19?: Three filed components: a seasonal base charge on the monthly all-hours peak, a basic charge billed on the trailing twelve-month demand, and a summer-evening component on a 7–11 p.m. window. For a site that draws its full hardware peak daily, each component resolves to the same monthly peak, and the model prices the sum — about $17.27 per kW bundled — exactly, overstating only where that assumption bends.

Sources

Model a Tesla V4 Supercharger site in Idaho — payback, NPV, IRR, and a 15-year cash flow from your own inputs.

Run a Idaho scenario

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ForgeAsset is software, not investment, tax, or legal advice — outputs are model estimates from your inputs, not guarantees. Rates and programs current as of research; verify current terms with each source before committing capital.