In short: Kauaʻi is the only Hawaii island served by a member-owned co-op, Kauaʻi Island Utility Cooperative (KIUC). Its homes paid 41.29¢ per kWh in 2024, the lowest in the state, and 35% of its solar homes have a battery, the highest share. In September 2026, Hurricane Lowell knocked out power to about 92% of KIUC’s members.
Below: what that means for backup power, solar, batteries and EV charging in Līhuʻe and around the island, and how KIUC and the county handle approvals. For statewide rules (the state tax credit, contractor licensing), see our Hawaii energy guide.
Kauaʻi at a glance
- Utility: Kauaʻi Island Utility Cooperative serves the whole island, about 35,300 customers. Homes paid 41.29¢ per kWh on average in 2024, all charges included (EIA-861). Its residential rate has an $11.42 monthly customer charge and base energy charges of about 40.9¢ per kWh, adjusted each month for fuel and purchased power.
- Outages (2024): 383 minutes per customer including major events, about 6.4 hours, and 219 minutes without them. Members averaged 4.4 interruptions, second only to Hawaiʻi Island.
- Sun: 5.88 kWh per square meter per day at Līhuʻe, the highest of our Hawaii metro points (NASA POWER, 2001–2020). Our rough estimate: about 1,720 kWh a year per kW of panels.
- Top hazards: FEMA’s National Risk Index (December 2025) rates Kauai County’s overall risk “relatively moderate.” Lightning rates “relatively high”; landslide, inland flooding, tsunami and wildfire “relatively moderate.” Hurricane rates only “relatively low” as a long-run average, which Lowell just tested.
- Public charging: 43 ports at 14 locations in Līhuʻe (AFDC, October 2026).
Your utility and what it means
KIUC is not part of Hawaiian Electric, so Hawaiian Electric’s export rates and its BYOD Plus battery incentive don’t apply here. What KIUC’s own solar pages say:
- Apply first: under Public Utilities Commission rules, you must file an interconnection application and pass KIUC’s engineering review before installing. For systems of 10 kW or less, which covers most homes, there is no application fee. KIUC acknowledges these within five business days and tells you within 15 days if anything is missing. Above 10 kW there’s a $100 fee.
- Exports under Schedule Q: KIUC pays for excess power at its “avoided cost,” a rate that changes monthly and follows the price of oil. KIUC expects it to drop as more renewable power comes online.
- Curtailment: on sunny afternoons Kauaʻi often has more solar than demand. “Oversized” export systems need a separate curtailment meter and can be told to cut output. KIUC’s right-sizing chart sets the largest system that avoids that meter, from 2.5 kW for homes using up to 500 kWh a month to 5.25 kW above 1,200 kWh.
Read the details and tariffs on KIUC’s rooftop solar page, or call KIUC at 808-246-4300 before you sign a contract.
Backup power on Kauaʻi
Hurricane Lowell passed about 80 miles west of Kauaʻi around September 8, 2026, as a Category 2 storm with gusts up to 85 mph. According to KIUC’s figures reported by NRECA, the national co-op association:
- 33,319 of KIUC’s 36,333 members, about 92%, lost power.
- Trees, poles and transmission lines came down, including broken transmission poles on the north shore.
- A week later, on September 15, about 6,500 members were still without power. A 250-person team, including about 100 mutual-aid workers from Hawaiian Electric, Southern California Edison and a contractor, worked on repairs.
Hawaiian Electric called it its largest help to Kauaʻi since Hurricane Iniki in 1992. The lesson for homes here is to plan for outages measured in days or weeks, not hours, especially outside Līhuʻe.
- Solar plus battery: keeps essentials running and recharges every sunny day; panels alone shut down when the grid is out. See home batteries.
- Generator: the backstop for a long, cloudy outage. Store fuel safely, run it outdoors at least 20 feet from the house with exhaust pointed away, and keep CO alarms inside (CPSC). See generator installation.
- Power station: a portable power station charged ahead of a storm covers phones, lights, Wi-Fi and medical devices.
Size a system with the battery backup calculator or the generator sizing tool, and compare options in our backup power guide.
Solar on Kauaʻi
EIA counted 5,917 home solar systems on KIUC’s grid in 2024, about one for every five residential members. Each kW of panels at Līhuʻe makes about 1,720 kWh a year by our estimate. Used at home, that saves roughly $700 a year at KIUC’s base energy charges, before the monthly fuel adjustment (an estimate, not a quote). Exports earn the monthly Schedule Q rate instead, and an oversized system can be curtailed at midday.
So on Kauaʻi the usual advice is to size solar to your own use and follow KIUC’s right-sizing chart. Check your roof with the solar potential tool and the solar savings calculator, and read how solar installation works, what it costs and how net metering and export credits work.
Home batteries on Kauaʻi
Kauaʻi leads Hawaii here: 2,073 of KIUC’s 5,917 home solar systems had a battery in EIA’s 2024 count, 35%, about twice the share on Hawaiian Electric’s islands. With midday surplus, curtailment and storm risk, a battery lets you keep your own solar for the evening and for outages. We didn’t confirm a current KIUC battery incentive, so ask KIUC before you buy. See battery costs and battery installation.
EV charging on Kauaʻi
At about 30 kWh per 100 miles and KIUC’s base energy charges, charging at home costs roughly $12 per 100 miles before the monthly fuel adjustment (an estimate), less with your own solar at midday. Island distances are short, so a Level 1 outlet may do for light driving; a Level 2 charger needs a 240-volt circuit, a permit and a licensed electrician. We didn’t confirm a KIUC EV rate or charger rebate. See EV charger installation and the EV charging cost calculator.
Drive on another fuel? See every alternative fuel station in Lihue: hydrogen, propane, natural gas, E85 ethanol, biodiesel and renewable diesel.
Permits and inspections
- County of Kauaʻi, Department of Public Works, Building Division: 4444 Rice St., #175, Līhuʻe, (808) 241-4854. Plans can go through the county’s electronic plan review or on paper at the office, and the county works from the 2020 National Electrical Code. See its residential permit checklist and ask what it needs for solar, batteries, generators and chargers.
- KIUC: interconnection approval and engineering review before any solar or battery connects.
- Wiring: transfer switches, battery panels and chargers are work for a licensed electrician; the state page explains how to check a license.
In a condo or planned community, get written association approval before you sign.
Cities we cover
- Līhuʻe
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Kauaʻi energy questions
Does Hawaiian Electric’s BYOD Plus battery program apply on Kauaʻi?
No. BYOD Plus is offered on Oʻahu, in Maui County and on Hawaiʻi Island. Kauaʻi is served by KIUC, which sets its own programs and rates under the Hawaii Public Utilities Commission. Ask KIUC about any current battery or export options before you size a system.
What is KIUC’s Schedule Q?
It’s how KIUC pays for excess solar you send to the grid: an “avoided cost” rate that changes every month and is tied to the price of oil. KIUC says it expects the rate to fall as it uses more renewable power, so don’t count on export income to pay for a system.
Why might KIUC curtail my solar?
On sunny afternoons Kauaʻi’s grid often has more solar than it can use. Systems larger than KIUC’s right-sizing chart allows need a curtailment meter and can be asked to cut output. Sizing to your own use, from 2.5 kW for small users up to 5.25 kW for big ones, avoids that.
How long did power stay out after Hurricane Lowell?
About 92% of KIUC members lost power when Lowell passed around September 8, 2026, and about 6,500 were still out a week later, per KIUC’s figures reported by NRECA. Damage to north shore transmission poles slowed repairs. Homes outside Līhuʻe should plan for multi-day outages.
Sources
EIA-861, 2024 (price = residential revenue ÷ sales; reliability; net metering); KIUC Schedule D residential tariff (effective May 9, 2025) and rooftop solar page (archived copies, May and September 2026); NRECA report on Hurricane Lowell (updated September 15, 2026); Hawaiian Electric news releases (September 9, 2026) and BYOD Plus page; County of Kauaʻi Building Division residential permit checklist (August 2025); NASA POWER, 2001–2020; FEMA National Risk Index, December 2025; AFDC; CPSC. Read October 2026. Estimates are ours and labelled.