Idaho Solar Guide: Gem State Solar Economics

Idaho has solid solar potential with 4.5-5.0 peak sun hours, but some of America's lowest electricity rates make payback longer than high-rate states. Here's the honest analysis.

Quick Answer
Idaho has good sunshine (4.5-5.0 peak sun hours) but challenging solar economics due to ~$0.10/kWh electricity rates—among the lowest in America. Sales tax exemption on equipment helps, but no state tax credit and reduced net metering rates from Idaho Power extend payback to 12-18 years. Best for those prioritizing energy independence over quick financial returns.

Idaho Solar Overview

💡
From my experience:

I'll be straight with you—Idaho is one of the harder states to make solar pencil out quickly. The sunshine is great, especially around Boise and Twin Falls, but Idaho Power's rates are among the cheapest in America thanks to hydropower. When electricity costs $0.10/kWh, your panels produce plenty of power but each kilowatt-hour just isn't worth as much. That said, if you're building new and can integrate solar efficiently, or you value energy independence, it can still make sense for the long haul.

Idaho enjoys 200+ sunny days per year, with southern regions like Boise, Twin Falls, and Pocatello getting excellent solar irradiance. The challenge isn't the sun—it's that Idaho's electricity is already cheap. Low rates are great for your current bills but make it harder for solar to compete financially.

[Editor's Note, Feb 2026]:Idaho Power's net metering program offers reduced export rates rather than full retail credit. This significantly affects solar economics. Always verify current compensation rates with your utility before making installation decisions.
Idaho Solar Facts
Idaho averages 4.5-5.0 peak sun hours daily (higher in south). Electricity rates around $0.10/kWh are among the LOWEST in America. Annual production of 1,400-1,500 kWh per kW installed. Solar costs $2.50-$2.90/watt—below national average. (Source: NREL Solar Resource Data)

Regional Differences

Southern Idaho gets significantly better solar production than the northern panhandle:

  • Southern Idaho (Boise, Twin Falls): 4.8-5.0 peak sun hours
  • Eastern Idaho (Pocatello, Idaho Falls): 4.6-4.8 peak sun hours
  • Northern Idaho (Coeur d'Alene): 4.2-4.5 peak sun hours

State Incentives

Idaho Programs

  • Sales tax exemption: Solar equipment purchases exempt from state sales tax (~6% savings)
  • Property tax exemption: Solar value excluded from property tax assessments
  • Net metering: Available but at reduced rates (see below)
  • No state tax credit: Idaho does not offer a state solar tax credit

Federal Tax Credit (2026)

Ownership TypeFederal CreditNotes
Cash PurchaseNone25D residential credit ended Dec 2025
Solar LoanNoneSame as cash—no federal credit available
PPA/Lease30%Solar company claims credit, passes savings to you (through 2027)
Incentive Reality Check
With limited state incentives and no federal credit for purchased systems, Idaho solar economics depend heavily on: (1) your specific electricity usage, (2) roof suitability, and (3) your timeline and goals. Sales tax exemption saves ~6% on equipment, but that's about $1,200-$1,400 on a typical system.

Net Metering

Idaho Power Policy

  • Credit rate: Reduced export rate (not full retail)
  • Program: On-Site Generation program
  • System limit: Up to 25 kW for residential
  • Monthly rollover: Credits carry forward
  • Annual settlement: Excess credits paid at avoided cost rate
[Editor's Note, Feb 2026]:Idaho Power's reduced export rates mean you get credited LESS than retail for power you send to the grid. This is different from states with 1:1 net metering. Size your system for self-consumption rather than maximum export.

Rocky Mountain Power (Eastern Idaho)

  • Service area: Eastern Idaho (Idaho Falls, Pocatello)
  • Net metering: Schedule 135 for residential
  • System limit: Up to 25 kW
  • Credit rate: Varies by rate schedule
Net Metering Impact
Reduced export rates significantly affect solar economics. If Idaho Power pays you $0.05/kWh for exports but charges $0.10/kWh for consumption, you only get half value for excess production. Design your system to maximize self-consumption rather than exporting to the grid.

Solar Costs

Idaho solar costs run $2.50-$2.90 per watt, below the national average of $2.75-$3.25. Lower labor costs and competitive markets help keep prices down.

System SizeGross CostAfter Sales Tax ExemptionAnnual Production
6 kW$15,000-$17,400~$14,100-$16,4008,400-9,000 kWh
8 kW$20,000-$23,200~$18,800-$21,80011,200-12,000 kWh
10 kW$25,000-$29,000~$23,500-$27,30014,000-15,000 kWh

Savings & Payback Analysis

System SizeAnnual SavingsPayback Period25-Year Savings
6 kW$840-$90016-18 years$7,000-$10,000
8 kW$1,120-$1,20015-18 years$9,000-$13,000
10 kW$1,400-$1,50015-18 years$12,000-$17,000
💡
From my experience:

Those 25-year savings numbers look modest compared to high-rate states like California or Massachusetts where you might save $50,000+. That's the reality of Idaho's cheap power. But here's the thing—rates will likely increase over 25 years, and your solar panels lock in energy costs at today's price. If Idaho Power rates climb 3-4% annually, your savings could double.

Major Utilities

Idaho Power

  • Service area: Southern Idaho, Boise metro, Treasure Valley
  • Customers: ~600,000
  • Average rate: ~$0.10/kWh
  • Net metering: On-Site Generation program (reduced export rates)
  • Interconnection: Required for grid-tied systems

Rocky Mountain Power

  • Service area: Eastern Idaho (Idaho Falls, Pocatello area)
  • Average rate: ~$0.10-$0.11/kWh
  • Net metering: Schedule 135
  • Programs: Time-of-use rates available

Rural Electric Cooperatives

  • Coverage: Various rural areas throughout Idaho
  • Net metering: Varies by co-op—contact directly
  • Rates: Generally competitive with IOUs

Production Estimates by Region

  • Southern Idaho: 1,450-1,500 kWh per kW installed annually
  • Eastern Idaho: 1,400-1,450 kWh per kW installed annually
  • Northern Idaho: 1,300-1,400 kWh per kW installed annually
  • Best production months: May-August

The Bottom Line

Idaho's solar economics are challenging but not hopeless. The excellent sunshine is real—4.5-5.0 peak sun hours rivals many solar-friendly states. But when you're starting with $0.10/kWh electricity thanks to Idaho's abundant hydropower, the financial case takes longer to develop.

Solar makes the most sense in Idaho for homeowners who:

  • Value energy independence over quick financial returns
  • Are building new homes where solar integrates efficiently
  • Expect to stay long-term (15+ years) to realize full savings
  • Want to hedge against future rate increases
  • Have excellent south-facing roof exposure

If you're chasing fast payback, Idaho isn't your state. But if you're playing the long game and want to lock in energy costs while producing clean power, the math can work—just go in with realistic expectations.

Questions About Idaho Solar?

Our AI can help you understand Idaho Power programs, realistic payback expectations, and whether solar fits your specific situation.

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LP

Written by

Lincoln Panasy

Founder, SolarQuest AI • Solar Expert Since 2018

Lincoln created SolarQuest AI after seeing too many homeowners get burned by pushy solar salespeople. With 8 years of experience in the solar industry since 2018, he writes and reviews all content on this site—combining his real-world expertise with AI tools to deliver accurate, unbiased solar education.