First Solar Brand review

FS-6475-P-B

475 Wp Thin film Bifacial 15%

55 of 100

ComparePV verdict

Middle of its segment, modest efficiency

Rank 12,427 of 14,005

Compare panels Datasheet PDF

Power (Wp)

475

Typical for its class

Efficiency (%)

18.90

Weak · bottom 2%

Density (Wp/m²)

188.5

Weak · bottom 2%

Temp (%/°C)

-0.320

Typical · median -0.300

Weight (kg)

34.0

Weak · 10.0 kg above median

Warranty (yrs)

Typical · median 30 yrs

First Solar Series 6 Plus Bifacial is a breakthrough in thin-film technology that redefines performance in demanding environmental conditions. Unlike standard silicon cells, these modules utilize advanced CdTe (cadmium telluride) technology, which translates into significantly better spectral response and higher energy production in low light or heavy cloud cover. The use of a bifacial design allows for additional energy gain from the rear side of the panel, making this series an optimal choice for ground-mount installations with high albedo. A key differentiator is total resistance to light-induced degradation (LID) and potential-induced degradation (PID), ensuring trouble-free operation and stable power for decades. The panels feature an innovative frame design that prevents debris buildup on the edges, and the industry's lowest temperature coefficient guarantees high efficiency even in extreme heat. The Series 6 Plus Bifacial is dedicated to photovoltaic farms and commercial projects aiming to maximize return on investment. By choosing these modules, investors opt for the lowest carbon footprint and the highest reliability, distinguishing themselves from competitors using traditional crystalline silicon.

Ranking

7,948 panels in the 375-575 W band, all technologies

Metric This panel Median Position in segment Overall rank

Module efficiency 18.90% 21.52% Weak · bottom 2% 12,996

Power density 188.5 215.2 Weak · bottom 2% 12,993

Temperature coefficient -0.320 -0.300 Typical 8,312

Weight per kWp 71.6 52.5 Weak · bottom 2% 13,476

Performance warranty 30 yrs 30 yrs Typical 21

Colour key Strong - top 25% Typical - middle 50% Weak - bottom 25%

Signals from the data

5 positive · 4 caution

Best for

Commercial, utility-scale and hot-climate.

Not ideal for

Tight roof space, roofs where every square metre has to count and weight-limited structures.

Watch-outs

18.90% module efficiency

Bottom 2% of the 375-575 W band, against a median of 21.52%. Ranked 12,996th in the whole database.

188.5 watts per square metre

Bottom 2% of the 375-575 W band, against a median of 215.2. Ranked 12,993rd in the whole database.

71.6 kg per kWp

Bottom 2% of the 375-575 W band, against a median of 52.5. Ranked 13,476th in the whole database.

What owners get

Industry-Leading Temperature Coefficient

The Pmax temperature coefficient is -0.32%/°C (range 25–75°C), while standard crystalline modules typically achieve -0.35% to -0.40%/°C. For ground-mounted installations in a temperate climate, this translates into measurably higher annual energy yield during summer months at no additional cost.

Zero LID and LeTID Degradation

CdTe technology is inherently immune to light-induced degradation (LID) and light- and elevated temperature-induced degradation (LeTID) — phenomena that cause a 0.5–2% power loss in PERC/TOPCon silicon cells during the first years of operation. First Solar guarantees ≥90% of nominal power after 30 years, with a warranted annual degradation rate of just 0.3%/year.

30-Year Power Warranty — ≥90%

The manufacturer offers a 30-year linear power warranty with a floor of ≥90% at end of term. Segment peer comparables (Sunket, Gamko) typically provide a 25-year linear warranty with output declining to ~84.8%. This difference materially improves long-term project financial models (NPV, IRR).

Carbon Footprint 2.5× Lower Than c-Si

Life cycle assessment (LCA) data shows that the Series 6 Plus Bifacial module generates a 2.5× smaller carbon footprint and a 3× smaller water footprint than comparable monocrystalline modules — a compelling argument in project ESG due diligence and green financing procedures.

Pioneering CdTe Bifaciality — a Unique Product

The Series 6 Plus Bifacial is the world's first bifacial thin-film CdTe module, announced in June 2023. Its transparent rear contact transmits IR radiation rather than absorbing it as heat, lowering operating temperature and further boosting yield. Rear-side gain reaches up to 15% at high ground albedo, typical of utility-scale installations on light-colored soil or gravel.

Trade-offs

STC Efficiency Notably Below Peer Comparables

Module efficiency is 18.1–19.0% STC, whereas comparable 480 Wp products — the Sunket SKT460~480M10-120D3 and Shinson S-Blade BIPV — achieve 22.24%, and the Gamko GKA96N-PRO reaches 24.02%. To deliver equivalent plant capacity, a Series 6 Plus Bifacial installation requires approximately 20–26% more land area, resulting in higher land lease costs and BoS expenses on area-constrained projects.

Notes from the database

At 18.9% efficiency, this panel is 2.9pp below the database median of 21.8%
At 188.5 W/m², this panel generates 29.6 W/m² less per unit area than database median (218.1 W/m²)
-0.32%/°C temperature coefficient - 0.02pp worse than database median (-0.30%/°C), expect higher hot weather losses
At 34.0 kg, this panel is 7.5 kg heavier than the database median (26.5 kg) - more demanding for installation crews
Bifaciality factor of 15% can add 1-2% extra yield with reflective mounting surface

Specifications

Open datasheet PDF

Nominal power (Pmax) 475 Wp Nameplate at 1000 W/m², 25 °C

Module efficiency 18.90 % Weak Segment median 21.52%

Vmpp · Impp 191.50 V · 2.48 A Operating point at max power

Voc · Isc 224.80 V · 2.61 A Sizes the string length

Max system voltage 1500 V Longer strings than 1000 V modules

Dimensions 2024×1245 mm · 2.52 m² of roof

Weight 34.0 kg Weak Weak · 10.0 kg above median

Bifaciality 15 % Rear output as a share of front

Coefficient Pmax -0.320 %/°C Typical median -0.300 of its segment

Coefficient Voc · Isc -0.280 · 0.040 %/°C

NOCT 43 °C At 800 W/m², 20 °C ambient

Performance warranty 30 years Typical median 30 yrs · median 30 yrs

End-of-warranty output 89.3 % Equals 424 W guaranteed

Degradation 2.00 → 0.30 % First year, then annual

Simulations

Live - change any input

Lifetime output & value

30 years at 1200 kWh/kWp/year and €0.50 per kWh

Power in year 30

Lifetime energy

Energy value

With bifacial gain

Irradiance Energy price Price inflation 0%/yr

Degradation from this panel's own datasheet figures. No inverter, soiling or shading losses.

Heat losses

-0.320 %/°C against a segment median of -0.300

Try your own cell temperature (°C) 60° · - · -

Bifacial gain

Rear gain over light concrete: -

Model: bifaciality × albedo × 0.6 view factor. A first-order estimate, not a yield simulation.

Alternatives

All First Solar panels

Filter these Similar power Same cell type Same manufacturer

Size Any ±10 mm ±25 mm ±50 mm ±100 mm

Panel Power Eff. Temp. Weight Difference

First Solar FS-6475-P-B 475 W 18.90% -0.320 34.0 kg You are here

FS-6480-P-I / FS-6480A-P-I (SL) or FS-6480-P / FS-6480A-P (HL) 480 W 19.00% -0.320 34.0 kg Very close match

FS-6455-P-I / FS-6455A-P-I (SL) or FS-6455-P / FS-6455A-P (HL) 455 W 18.10% -0.320 34.0 kg -20 W, -0.8 pp

FS-6460-P-I / FS-6460A-P-I (SL) or FS-6460-P / FS-6460A-P (HL) 460 W 18.30% -0.320 34.0 kg -15 W, -0.6 pp

JT590SJk(B) 590 W 23.10% -0.240 30.7 kg +115 W, cooler, +4.2 pp

RS9V-M-DG-590 590 W 23.08% -0.300 31.2 kg +115 W, lighter, +4.2 pp

JT585SJk(B) 585 W 22.90% -0.240 30.7 kg +110 W, cooler, +4.0 pp

RS9V-M-DG-585 585 W 22.88% -0.300 31.2 kg +110 W, lighter, +4.0 pp

GKA210N108-580W 580 W 22.71% -0.340 25.5 kg +105 W, lighter, +3.8 pp

JT580SJk(B) 580 W 22.70% -0.240 30.7 kg +105 W, cooler, +3.8 pp

RS9V-M-DG-580 580 W 22.69% -0.300 31.2 kg +105 W, lighter, +3.8 pp

GKA210N108-575W 575 W 22.51% -0.340 25.5 kg +100 W, lighter, +3.6 pp

JT575SJk(B) 575 W 22.50% -0.240 30.7 kg +100 W, cooler, +3.6 pp

RS9V-M-DG-575 575 W 22.49% -0.300 31.2 kg +100 W, lighter, +3.6 pp

Found 30 panels of the same or similar size to this one, within ±10 mm. See them here Found 44 panels of the same or similar size to this one, within ±25 mm. See them here Found 44 panels of the same or similar size to this one, within ±50 mm. See them here Found 91 panels of the same or similar size to this one, within ±100 mm. See them here

Common questions

6 answered

What warranty does the First Solar Series 6 Plus Bifacial carry?

First Solar offers a 30-year linear power warranty on this series, guaranteeing 98% of nominal output at the end of the full warranty period with an annual degradation rate of only 0.3%. This is complemented by a 12-year product warranty covering material and workmanship defects. The combined package is one of the most competitive warranty offerings in the photovoltaic industry, significantly exceeding the 10–12-year product warranties typically provided by silicon-based module manufacturers.

How does the CdTe technology in the First Solar Series 6 Plus Bifacial differ from standard silicon-based modules?

The Series 6 Plus Bifacial uses cadmium telluride (CdTe) thin-film technology instead of crystalline silicon. Key differences include: superior spectral response under overcast and low-irradiance conditions (resulting in higher energy yield on cloudy days), complete absence of LID and PID degradation, the lowest temperature coefficient in the industry (minimizing power losses during high-temperature operation), and the lowest carbon footprint per watt produced. This technology is designed for utility-scale PV farms rather than residential prosumer installations.

What is the temperature coefficient of the First Solar Series 6 Plus Bifacial, and what does it mean in practice?

The First Solar Series 6 Plus Bifacial features one of the lowest temperature coefficients among commercially available photovoltaic modules. In practical terms, on hot days when module surface temperatures reach 40–50 °C, it loses significantly less power than typical polycrystalline or monocrystalline PERC modules. For a utility-scale farm operating during extended summer periods at elevated temperatures, this translates directly into additional kilowatt-hours of generation and an improved return on investment.

Is the First Solar Series 6 Plus Bifacial suitable for rooftop installations or only for ground-mounted systems?

This series is designed exclusively for ground-mounted utility-scale farms and large commercial installations, not for residential rooftop use. The module weighs approximately 33 kg and has the large form factor typical of utility-scale modules. The bifacial construction delivers its greatest benefits in ground-mounted configurations, where white gravel ballast or light-colored soil increases albedo and improves rear-side energy yield by an additional few to over ten percent.

What additional energy yield does the bifacial construction provide in this series?

The Series 6 Plus Bifacial is the world's first bifacial CdTe thin-film module. The rear side of the panel absorbs irradiance reflected from the ground surface (albedo), which — with a light-colored ground cover such as gravel, concrete, or pale soil — delivers additional energy yield of several to over ten percent above the nominal 480 W rating. The effective bifacial gain depends on ground albedo, mounting tilt angle, and module height above ground.

How reliable is First Solar as a manufacturer, and what does Tier 1 status mean?

First Solar is a U.S.-based manufacturer headquartered in Arizona that has been consistently classified as a Tier 1 module supplier by independent rating agencies, including Bloomberg NEF. Tier 1 status means the manufacturer meets rigorous financial and technical criteria, enabling banks and lenders to finance projects using its modules without applying additional technology risk premiums. First Solar is one of the few Western manufacturers capable of competing with Chinese factories at scale — a factor of considerable importance for long-term warranty servicing and supply chain reliability.

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