Solar Replacement & Upgrade Shopping Guide (In-Depth)

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Solar systems include live AC and DC equipment. A licensed pro will evaluate hazards, pull permits, and follow code and manufacturer instructions. Do not open inverters, combiner boxes, or panels yourself.

Even partial shading can drop production across an entire string. Strategic pruning or removal can dramatically increase annual energy yield.

Accumulated dust, pollen, and bird droppings reduce power. Periodic cleaning and checking for firmware updates or optimizer/inverter faults can restore lost production.

Output slowly declines over time. Replacing underperforming modules and addressing wiring or inverter issues can improve system performance.

If a roof is near end-of-life, re-roof first. This avoids removing arrays later and helps maintain warranties and weather integrity.

Confirm mounting methods approved by your shingle or roof manufacturer. Use compatible flashings and fasteners and document the installation for warranty records.

Prioritize high-irradiance roof faces and allow safe access for occasional glass cleaning, snow removal, or service.

Shorter wiring between arrays, inverters, and combiner or gateway equipment reduces voltage drop and improves efficiency.

Storage increases resiliency, shifts solar energy into evening hours, and can participate in time-of-use savings or backup power strategies.

Smart panels, energy monitors, and load controllers help manage large loads during cloudy weather or outages and can optimize self-consumption.

Label disconnects, inverters, batteries, and sub-panels. Keep enclosures latched or locked and out of child reach. Provide one-line diagrams for future service.

Degradation is the rate at which a panel loses output over time. Better modules have lower annual degradation and higher warranted energy after 25 years.

Incentives can change. Verify Washington sales tax treatment for battery storage connected to solar, and confirm eligibility for the 30% federal Investment Tax Credit.