Hawaii's 2026 Hurricanes: Backup Power Lessons

Oct 12, 2026 - Lucas Ballek - 8 min read

Last reviewed: October 22, 2026

The 2026 storms affected different islands in different ways. Their reports are useful for planning, but they do not predict what a future storm will do to a particular home. A backup plan should start with the loads you need to keep running and the equipment you already have.

The season, by the numbers

Lala: The National Weather Service reports that Hurricane Lala made a direct hit as a Category 1 hurricane over the Big Island on August 15. An observation near South Point measured 51 mph sustained wind and a 71 mph gust. A federal emergency declaration followed Tropical Cyclone Lala; it was not a disaster declaration.
Lowell: At 6:40 a.m. on September 8, Kauai County reported that about 90% of more than 36,000 Kauai Island Utility Cooperative customers were without power. That is a time-specific outage report, not a season-long rate.
Nolo: In late September, the National Weather Service reported that Nolo turned west south of the island chain, while heavy rain contributed to flooding and road closures on Maui, the Big Island, and Kauai.

What an outage can affect

Power loss can interrupt more than lights and refrigeration. Kauai's Department of Water warned that outages can affect pumps and wells, interrupt service, or lower water pressure. Follow local water and emergency notices; a private well or catchment setup may have different limits from a municipal supply.

If someone depends on powered medical equipment, ask the device maker which backup sources are approved, and tell the electric utility and fire department about the power-dependent device. FDA guidance says people who depend on life-support equipment should contact emergency services and, when possible, their local public health authority before severe weather.

Size the loads you need to support

There is no single battery size that covers every household. List each critical device, its running watts, any starting surge, and the hours it must operate. Estimate daily energy as watts multiplied by hours, then check usable battery energy, inverter limits, and the device maker's requirements with a qualified installer.

A grid-connected solar array does not automatically provide backup power. The system must be configured to operate in island mode, with compatible storage and switching equipment. The calculator provides an estimate from your inputs and modeled weather; it does not guarantee outage runtime, especially when storm clouds limit solar production.

Compare backup options on their limits

A battery is limited by its usable energy and its ability to recharge. A generator depends on available fuel and safe operation. Neither is a universal winner. Compare the loads, runtime, refueling or recharge needs, installation, and maintenance for your situation.

Never run a portable generator indoors or in an enclosed space. The Consumer Product Safety Commission says to operate it outdoors at least 20 feet from buildings, with exhaust directed away from windows, doors, and vents. Follow the manufacturer's instructions, especially in wet weather.

What Hawaiian Electric's BYOD Plus program offers

Hawaiian Electric's Bring Your Own Device Plus program offers a one-time incentive of $400 per committed kW. Eligible low-to-moderate income participants may receive an additional $400 per committed kW. Hawaiian Electric's example uses a 15-kWh battery that commits 5 kW for two hours; the one-time incentive is $2,000. If the system is leased, the leasing company is the system owner and may receive the upfront incentive.

Participation requires a five-year agreement, a customer-selected two-hour dispatch window each day, and eligible equipment. The household is served first; only excess energy is targeted for export. Monthly credits vary with the customer's rate and island. Check current program eligibility and terms before making a purchase or signing an agreement.

Prepare before the next warning

Write down the critical loads and their required runtimes, including any medical-device instructions and starting surges.
Ask the equipment maker or a qualified electrician whether your inverter, battery, and transfer equipment will safely support those loads during a grid outage.
Test backup equipment before storm season. Keep batteries and medical-device supplies dry, and follow the manufacturer's storage and charging directions.
If using a generator, store fuel as local rules allow and use the generator outdoors at least 20 feet from buildings.
Monitor official weather, utility, and county updates. Keep drinking water and essential supplies based on local emergency guidance.

Related guides

Frequently asked

How do I size battery backup for a Hawaii storm outage?

List each critical device's running watts, any starting surge, and the hours it must operate. Estimate energy as watts multiplied by hours, then check usable battery energy, inverter limits, and the device maker's requirements. There is no single size for every home, and a calculator estimate does not guarantee outage runtime.

Does Hawaiian Electric's BYOD Plus program pay for a battery?

The program offers a one-time $400 per committed kW, plus another $400 per committed kW for eligible low-to-moderate income participants. A Hawaiian Electric example uses a 15-kWh battery committing 5 kW for two hours and shows a $2,000 one-time incentive. A leasing company may be the system owner and receive the upfront incentive. Check current eligibility and terms before enrolling.

Should I use a generator or a battery during an outage?

Compare the loads, runtime, fuel or recharge needs, and installation for your situation. A portable generator must be outdoors at least 20 feet from buildings, with exhaust directed away from windows, doors, and vents. Follow the manufacturer's safety instructions.

Will rooftop solar keep working when the grid fails?

Do not assume it will. The system must be configured to operate in island mode with compatible storage and switching equipment. Ask the equipment maker or a qualified installer to confirm how your system behaves during an outage.