Question 1

Does Solar Work on Cloudy Days?

Accepted Answer

Yes! Solar panels produce electricity from all daylight, not just direct sunlight. On cloudy days, panels typically produce 10-25% of their rated capacity. California's high annual sunshine means this is rarely a significant concern — most systems are designed to overproduce during sunny months to offset any cloudy periods.

Germany, which has significantly less sunshine than any part of California, is one of the world's leading solar nations — proving that solar works effectively even in less-than-ideal conditions.

Question 2

Do I Need a Battery?

Accepted Answer

You don't technically need a battery — but in California today, it's become one of the smartest investments you can make alongside solar.

Here's why:

• NEM 3.0 changed everything. Under the new net metering rules, excess solar energy exported to the grid earns significantly less credit than before. A battery lets you store that excess power and use it at night or on cloudy days, maximizing the value of every kilowatt-hour your panels produce.

• Time-of-Use (TOU) rates. California utilities charge much higher rates in the evening (typically 4–9 PM). Without a battery, you'd be buying expensive grid power at peak hours. With a battery, you discharge your stored solar energy instead — avoiding those peak charges entirely.

• Grid outage protection. California's aging grid, combined with wildfire-related Public Safety Power Shutoffs (PSPS), means outages are a real risk. A battery keeps your home powered when the grid goes down — something solar panels alone cannot do.

• Self-sufficiency. Homeowners with a properly sized solar + battery system can cover 80–100% of their energy needs without relying on the grid, providing both financial savings and peace of mind.

The most popular home battery options in California include the Tesla Powerwall, Enphase IQ Battery, and Franklin WH. Many qualify for the federal 30% Investment Tax Credit (ITC) when installed alongside solar.

Question 3

How Long Does Installation Take?

Accepted Answer

The actual installation of solar panels typically takes just 1–3 days. However, the full process from signing a contract to turning on your system takes longer due to permitting and utility approval:

• Site assessment & design: 1–2 weeks
• Permitting (city/county approval): 2–6 weeks depending on your jurisdiction
• Installation: 1–3 days
• Utility interconnection approval: 2–8 weeks

Total timeline: most California homeowners go from contract to activation in 2–4 months. Your installer will manage all permitting and utility paperwork on your behalf.

Question 4

What Size System Do I Need?

Accepted Answer

System size depends on your electricity usage, roof space, and financial goals. Here's a general framework:

• A typical California home using 700–900 kWh/month needs a 6–8 kW system.
• To estimate your size: divide your monthly kWh usage by your region's peak sun hours (4.5–6 in California), then divide by 30 days.
• Roof orientation and shading also matter — south-facing roofs with no shading are ideal, but west-facing panels can be strategically valuable for capturing afternoon sun during peak TOU hours.
• Under NEM 3.0, oversizing your system is less beneficial than before. Installers now typically design systems to offset 90–100% of usage rather than overproduce.

A professional site assessment will account for all these factors and recommend the optimal configuration.

Question 5

What Warranty Coverage Should I Expect?

Accepted Answer

Quality solar installations come with multiple layers of warranty protection:

• Panel performance warranty: 25 years — guarantees panels produce at least 80–90% of rated output over their lifetime.
• Panel product warranty: 10–25 years covering defects in materials or workmanship.
• Inverter warranty: 10–25 years depending on manufacturer (string inverters typically 10–12 years; microinverters up to 25 years).
• Battery warranty: typically 10 years or a set number of charge cycles (e.g., Tesla Powerwall: 10 years with 70% capacity guarantee).
• Installer workmanship warranty: 5–10 years covering the installation quality, roof penetrations, and labor.

Always ask your installer for full warranty documentation before signing. Reputable installers are CSLB-licensed and carry liability insurance.

Question 6

Will Solar Eliminate My Electricity Bill?

Accepted Answer

Solar significantly reduces your electricity bill — but a $0 bill is rare without battery storage and careful system design.

Here's what to expect:

• Most homeowners offset 80–100% of their electricity usage with a properly sized system.
• Under NEM 3.0, you'll still receive a monthly "Minimum Bill" from your utility (typically $10–15/month) even if you produce more than you consume.
• Without a battery, you'll still draw from the grid in the evening and pay TOU rates. Adding a battery can push your net bill close to zero.
• True energy independence — covering nearly all usage including an EV — is achievable with a solar + battery system sized appropriately.

The goal isn't necessarily a $0 bill; it's dramatically reducing what you pay and locking in long-term price stability as utility rates continue to rise.

Question 7

Is My Roof Suitable for Solar?

Accepted Answer

Most California homes are good candidates for solar, but several factors determine suitability:

• Roof age: If your roof is more than 10–15 years old, installers may recommend replacing it before installation to avoid removing panels later.
• Roof material: Asphalt shingle and tile are ideal. Metal roofs are also excellent. Flat roofs can work with tilt mounts.
• Shading: Trees, chimneys, or nearby structures that cast shade during peak hours (10am–3pm) reduce output. Microinverters or power optimizers can mitigate partial shading.
• Roof space: A typical 7 kW system requires approximately 400–500 sq ft of usable roof space.
• Orientation: South-facing is optimal; west-facing captures peak-hour afternoon sun which is valuable under TOU pricing.

A free site assessment from a licensed installer will evaluate all of these factors and tell you exactly what's possible for your home.

Question 8

What Happens When I Sell My Home?

Accepted Answer

Solar panels are treated as a home improvement and add significant value. Key points:

• Owned systems transfer with the property and increase resale value by an average of 4.1% (Zillow).
• Leased or PPA systems require the buyer to assume the lease/agreement or the seller to buy out the lease before closing.
• California law (AB 1070) requires sellers to disclose whether the system is owned, leased, or financed.
• Most real estate agents report that solar homes sell faster and at a premium in California's market.

Your Complete California Solar Education

The Comparison Engine

Compare Solar Financing Paths

California Solar Policies Explained

NEM 3.0 (Net Billing Tariff) — What Changed

Federal Investment Tax Credit (ITC) — Commercial Only

Owning vs. Leasing Your Solar System

California State Incentives & SGIP

California Solar Consumer Protections

Battery Storage in the NEM 3.0 Era

How Solar Installation Works

Frequently Asked Questions