Solar Panel Types + Technology Reference

Overview

Three main solar panel technologies dominate residential. Understanding the difference helps with customer selection + diagnostic.

Monocrystalline silicon (most common residential)

• Material: single crystal of silicon
• Appearance: uniform dark color (black or dark blue)
• Efficiency: 19-23% (highest commercial)
• Lifespan: 25-30 years
• Cost: panel
• Best for: most residential (best space efficiency)

Sub-types

PERC (Passivated Emitter Rear Contact) - most modern mono:

• Increased back-side reflection
• Higher efficiency (1-2% over standard mono)
• Now standard in premium residential panels

N-type (vs older P-type):

• Better low-light performance
• Lower temperature coefficient
• Premium pricing
• Examples: Maxeon, SunPower, REC

Polycrystalline silicon

• Material: multiple silicon crystals melted + cooled
• Appearance: blue, speckled
• Efficiency: 16-19%
• Lifespan: 25 years
• Cost: panel
• Best for: budget residential, ground mounts where space less constrained

Less common in new residential as monocrystalline costs have dropped.

Thin-film

• Material: amorphous silicon, CdTe, CIGS on glass substrate
• Appearance: flexible, lighter
• Efficiency: 11-15%
• Lifespan: 20-25 years
• Cost: variable
• Best for: specialty applications (boats, RVs, large commercial)

Not common in residential.

Bifacial panels

• Material: mono or poly, but with rear cell access
• Appearance: glass-glass construction (transparent back)
• Production: gains 10-25% from ground reflection (albedo)
• Lifespan: 30+ years (glass-glass durable)
• Cost: 10-15% premium over standard
• Best for: ground mounts, light surfaces below, light-colored roofs

Less common in residential rooftop (rooftop doesn't reflect well).

Sizing per panel

Common sizes:

• 60-cell (132 × 220 cm): 300-350 W
• 72-cell (200 × 100 cm): 380-450 W
• 96-cell (200 × 100 cm): 500-600+ W

72-cell common in residential; 96-cell increasingly so.

Power ratings

STC (Standard Test Conditions):

• 25°C cell temp
• 1000 W/m² irradiance
• Standard atmospheric mass

Real-world production typically 70-85% of STC rating due to:

• Temperature (panels run hot)
• Soiling
• Wiring losses
• Inverter efficiency

A 400W STC panel: typically produces 280-340W in real conditions.

Tier 1 vs Tier 2 vs Tier 3

Tier 1 manufacturers:

• Bloomberg's classification
• Bankable (lenders + insurers prefer)
• Top 20+ globally
• Examples: LG, Q Cells, REC, Panasonic, Maxeon (SunPower), JA Solar, Trina, JinkoSolar
• Premium pricing (10-25% over Tier 2)

Tier 2:

• Smaller manufacturers
• Quality decent but less proven
• Mid-tier pricing
• Bankability question for some

Tier 3:

• New / smaller / unstable manufacturers
• Higher warranty risk
• Lowest pricing

For residential 25-year systems: recommend Tier 1 panels.

Performance warranties

Standard panel warranty:

• 25 years to 80% of nameplate
• Some premium: 25 years to 92%, OR 40 years

Manufacturing warranty:

• 10-12 years against defects
• Premium: 25 years (same as production)

Coverage typically:

• Defective panels replaced
• NOT installation labor (customer needs reinstall help)
• Some programs include labor

Temperature coefficient

How panel output decreases as temperature rises:

Less negative = better high-temperature performance.

In hot climates (Phoenix, Vegas), N-type mono outperforms standard mono by 5-10% annually.

Manufacturers + reputation

Premium tier:

• LG NeON (production discontinued 2022 but service ongoing)
• SunPower Maxeon (made by SunPower, premium)
• Panasonic (premium ENERGYBOX)
• REC Alpha series

Mid-premium:

• Q CELLS Q.PEAK
• Canadian Solar
• Jinko Tiger Pro / Neo
• Hanwha Q Cells
• Hyundai

Budget:

• Generic Tier 2/3
• Bargain brands at big-box stores

Manufacturing + supply chain

Most residential panels:

• Manufactured in China, Vietnam, Malaysia, Korea (Asia-Pacific dominant)
• Some US-made (premium prices): SunPower (some), Mission Solar
• Tariffs + trade policy affect pricing volatility

When customer asks "which brand?"

Recommend tier 1 with focus on:

• Production warranty + tier 1 status
• Aesthetic preference (all-black for modern look)
• Efficiency (high-density panels for limited roof space)
• Bankability (resale value of home with system)
• Local installer support (warranty claims easier if local)

Roof space considerations

If roof space is limited, higher-efficiency panels matter:

• 300W panel: ~17 sq ft
• 400W panel: ~21 sq ft
• 500W panel: ~26 sq ft

For 6kW system: 12-20 panels depending on wattage.

Higher wattage panels: fewer needed, but each more expensive.

End-of-life + recycling

Panels reaching 25+ years:

• Recycling programs increasingly available
• Some manufacturer take-back programs
• Cost: typical
• Components recyclable: aluminum frames, glass, some metal cells
• Solar industry organizing recycling infrastructure

Common installation considerations

• Color match: many roof installations prefer all-black aesthetic
• Roof orientation: South-facing optimal in Northern Hemisphere
• Tilt: optimal = local latitude; flatter for summer; steeper for winter
• Shading: avoid; bypass diodes help but still costly to production

Selection decision matrix

References

• NREL panel efficiency data
• SEIA technical standards
• IEC 61215 (panel testing standard)
• Manuall internal: Residential Solar PV Installation SOP