Sunpower solar panels: our opinion (2024)

110 000. The number of French households with photovoltaic solar panels on their roofs (Enedis). By 2030, this number is set to rise to 4 million homes (Réseau de Transport d'Electricité forecasts)! 

Are you planning to install panels on your roof to reduce your energy bill and do your bit for the planet? Then there's the question of which brand to choose, because not all brands are created equal. 

In the premium segment, it's hard to ignore American brand SunPowera world leader in its field, thanks in particular to its patented Maxeon® solar cell technology. What are the panels from this major player in photovoltaics really worth? We give you all the consumer reviews and our opinion on photovoltaic panels Sunpower.

Once upon a time... SunPower 

SunPower was (unofficially) born out of the oil crisis of the 1970s, to which Dr. Richard Dawson was trying to respond by developing an alternative energy solution. Fascinated by the solar cells that equipped satellites, he set himself the ultimate challenge: to make these cells more cost-effective and accessible. It was a quest that, almost 40 years later, has made SunPower a leader in residential and commercial solar power generation.

While Professor of Electrical Engineering at Stanford University, Richard Dawson obtained grants from the Electric Power Research Institute and the U.S. Department of Energy to support his research into solar energy. With these funds, coupled with the financial backing of two venture capital firms, he founded SunPower in 1985.

Over the years, the company has built a solid reputation for its high-efficiency solar panels, thanks in particular to its patented Maxeon® solar cell technology. In 2020, following an investment of nearly $300 million by Tinajin Zhonghuan Seminconductor Co. (TZS), SunPower spun off its manufacturing division to create Maxeon Solar Technologies (alongside SunPower), a Singapore-based company dedicated to the production of solar panels, marketed under the "SunPower" brand. The company has production facilities in France, Malaysia, Mexico, China and the Philippines. 

In the same year, SunPower is ranked the number one provider of commercial solar solutions in the United States for the third year running. Also in 2020, the manufacturer launches an all-new system, dubbed OneRoof™, a rooftop solar panel specially designed for new homes. 

Since its (official) creation in 1985, SunPower has accumulated innovations... some would say feats: 

• SunPower's high-efficiency solar panels enabled a Honda car to win the "World Solar Challenge", a race across Australia, in 1993, beating the runner-up by a full day;
• In 1997, SunPower's high-efficiency solar cells powered NASA's Pathfinder prototypes, solar-powered high-altitude drones. That same year, the Pathfinder Plus model reached a record altitude of 21,800 meters;
• In 2007, SunPower launched mass production of its record-breaking high-efficiency solar cell, with an average conversion efficiency of 22.4 % ;
• In 2008, SunPower announced a prototype monocrystalline silicon solar cell with an efficiency of 23.4 %, a world record at the time;
• In 2009, PlanetSolar chose SunPower's high-efficiency solar cells to power the world's largest solar-powered catamaran.

SunPower Photovoltaic Panels

When we hear the name SunPower, the first word that usually springs to mind is this: Maxeon. This is the manufacturer's flagship model, on which it offers a 40-year warranty, the longest in the solar energy sector! 

Maxeon is a patented solar cell technology featuring extremely high efficiency, exceptional reliability and durability. In addition to the historic Maxeon range, SunPower also offers a "Performance" series. An overview.

Maxeon, SunPower's historic line

SunPower's Maxeon photovoltaic solar panels feature a "back contact", a solid copper panel that acts as a connector, boosting the production area and extending the life of these panels, which occupy a special place in the residential photovoltaic landscape. 

Naturally, longevity goes hand in hand with preserving product performance, with one of the lowest annual production decline rates on the market. Maxeon continues to produce 92 % of its rated power after 20 years of loyal service! Rear panel protection delays wear and tear. 

Another key advantage of SunPower residential photovoltaic panels is that they are the only ones to boast a peak power of over 430 Wp, the highest on the residential solar panel market. 

The Maxeon range comprises several models, each offering different levels of performance and efficiency:

• Maxeon 3the highest-performance solar panel in the Maxeon range: with a conversion efficiency of up to 22.7 %, it's the ultimate in residential applications. The Maxeon solar cells in this panel are designed to resist corrosion and thermal stress, guaranteeing exceptional durability and reliability. Maxeon 3 panels are available in wattages from 390 to 430 W.
• Maxeon 6 With an efficiency of up to 22 %, this solar panel is an interesting option for those looking for a good compromise between cost and performance. Maxeon 6 solar panels are designed for maximum energy production, even in conditions of high temperature and low light. They remain highly efficient even on cloudy days. Each panel features an integrated micro-inverter for independent operation, limiting the impact of shadows and improving overall system performance. Maxeon 6 panels are available in wattages from 410 to 435 W.

Whether you choose a model from the Maxeon 3 or 6 range, SunPower is committed to offering you : 

• A 40 year warranty, covering the product and the power;
• Guaranteed minimum power in the first year of 98 % ;
• A maximum annual degradation rate of 0.25 %.

Performance" range, excellent value for money 

Unlike the Maxeon range, Performance solar panels use high-efficiency PERC monocrystalline cells, rather than back-contact technology. The power range is slightly lower than that of the Maxeon series (375 Wp to 415 Wp), and the maximum efficiency of the Performance series is 21.1 % (Performance 6 panel).

Once again, the Performance range is available in two flagship models, each offering different levels of power:

• Performance 3: available in wattages from 370c to 390 Wp ;
• Performance 6: available in wattages from 375c to 415 Wp.

The main features of the Performance range are as follows: 

• The Performance range uses PERC (Passivated Emitter Rear Contact) monocrystalline solar cell technology, which delivers higher energy efficiency than traditional solar cells. This technology also improves solar panel performance in low-light conditions;
• SunPower's Performance solar panels show an efficiency of up to 20 %, which is slightly lower than that of Maxeon solar panels... but still within the market average at this price level ;
• The Performance range is designed to withstand harsh climatic conditions, and comes with a 25-year warranty on product performance and quality.

Aesthetics of SunPower PV panels 

SunPower promises one thing: you won't have to choose between aesthetics and functionality. In fact, the American manufacturer strives to combine the two, and the gamble is quite successful.

In our opinion, SunPower solar panels offer impeccable aesthetics, thanks in particular to anti-reflective glass that reduces glare, making them suitable for a variety of architectural styles. We're particularly impressed by the all-black lacquered panels - not only the frame, but also the support and cells - without losing any of their performance. 

An ideal solution for slate roofs, these panels integrate like a Velux window. Cables are concealed beneath the panels for a more flattering appearance.

The performance of SunPower photovoltaic panels 

Remember that solar panels perform best when maintained at a temperature of around 25°C. To measure a solar panel's performance, we use the temperature coefficient, an indicator that shows how your panel's performance changes on hot, sunny summer days.

For every degree above 25°C, your solar panel's electricity output will decrease by its temperature coefficient. The temperature coefficient of all SunPower panels is 0.29 %/°C. This means that if the panel's temperature rises by one degree from 25°C, its electricity output will drop by 0.29 %. If its temperature rises to 35°C, electricity production will drop by 2.9 %... quite a performance.

In terms of efficiency, SunPower launched the first 400 W residential solar panel in 2019. At the time, it was the world's most efficient residential panel, with an efficiency of 22.6 %. The Maxeon 2 and Performance 3 solar panels also boast impressive efficiencies of 20.4 % and 19.9 %, respectively.

On another note, solar panels typically lose 2.5 % of power in the first year of operation (and 0.7 % in each subsequent year), whereas SunPower photovoltaic panels guarantee a minimum of 98 % of power in the first year. This means that a conventional solar panel will retain 80 to 82 % of its rated output after 25 years, whereas the Maxeon range boasts an industry-leading maximum annual degradation rate of just 0.25 %, remaining at around 88 %.

This is made possible by high-performance IBC (Interdigitated Back Contact) cells, which SunPower began mass-producing in 2007. SunPower's IBC cells are built on a base of high-purity N-type silicon, which increases efficiency and performance at a very low degradation rate. This is the basis for SunPower's highest performance guarantee of 88.25 % of retained capacity after 40 years, on panels in the Maxeon range.

To help you see things more clearly, here is a table summarizing the main performance indicators for the two flagship models in the Maxeon and Performance ranges (Maxeon 3 and Performance 6): 

	SunPower Maxeon 3	SunPower Performance 6
Number of cells	104 cells	104 cells
Type of cells	Maxeon Gen III Monocrystalline	Single crystal PERC
Output power (peak)	400 Wp	410 Wp
Nominal voltage	65,8 V	29,9 V
Panel efficiency	22,6 %	20,9 %
Annual power degradation	0,25 %	0,45 %
Dimensions	1690 x 1046 x 40 mm (1.77 m²)	1808 x 1086 x 30 mm (1.96 m²)
Weight	19 kg	21 kg
Product Warranty	40 years old	25 years old
Performance guarantee	40 years old	25 years old
Operating temperature range	- 40 °C to 85 °C	- 40 °C to 85 °C
Manufacturing	Philippines	China
Assembly	Mexico	China

User reviews of SunPower solar panels 

For the media, there's no doubt: SunPower is THE reference in photovoltaic panels. But what do users think? On the whole, opinions are largely positive, as this selection of verified reviews shows. 

" When I called SunPower to find out what the cost would be compared with the other products I'd evaluated, the company was competitive, which rather surprised me. In fact, the price was significantly lower than the previous offer I had obtained, partly because the yields are very high and the quality offered by the other product would require more panels, which would increase the cost. "(March 31, 2022)

" We decided to go solar with SunPower on the recommendation of our university alumni association. We had wanted to go solar for some time, but needed a company we could trust. SunPower lived up to our expectations, providing us with excellent service.. " (March 17, 2023)

" I've decided to add a photovoltaic system to my home to make it more energy efficient. It's important for me to run my home primarily on green energy to reduce my carbon footprint. I chose SunPower because they provided me with the most cost-effective solution, the best product platform and the best long-term support. "(March 17, 2023)

" We had an excellent contact who helped us move the process forward, but other people in the company didn't react as quickly and didn't move the project forward. I opted for solar energy both to save money and to respect the environment. "(March 16, 2023)

SunPower's strengths and weaknesses

The advantages

SunPower is a global leader in its sector, and has a number of strengths. To recap: 

• The highest conversion rate on the market: SunPower panels are capable of converting more sunlight into electricity, with a conversion rate of up to 22.8 % ;
• A record 40-year warranty on Maxeon products and performance, and a 25-year warranty on all others;
• The panels retain more than 88 % of their power after 40 years;
• Reviews of SunPower solar panels are largely positive, and the brand is appreciated by experts and users alike;
• Broad product range: SunPower offers panels primarily for residential installations, but also flexible panels, high-efficiency modules for commercial installations and bifacial panels. The company also offers energy storage systems.

The disadvantages 

SunPower also has its weaknesses, but they are far outweighed by its advantages: 

• SunPower solar panel prices are among the highest on the market, if not the most expensive;
• SunPower focuses more on residential projects. Although the company offers panels for commercial and mobile solar installations, this is not its specialty. As a result, SunPower panels for these applications are not as advanced and competitive as those of the competition.

What are the alternatives to SunPower?

DualSun

The first that springs to mind is DualSun, a high-quality, 100 % French alternative to SunPower. Combining reliability and (above all) innovation with its hybrid panels, DualSun offers more than respectable performance, coupled with handsome robustness.

Read our opinion on Dualsun photovoltaic solar panels

Other alternatives to consider 

True to the reputation of its parent company, LG Solar offers robust solar panels with attractive yields. When it comes to innovation and performance, SunPower is always one step ahead, but LG Solar photovoltaic panels also have their strengths: elegant design, respectable yield, generous warranties and attractive value for money.

A number of other major manufacturers have also entered the photovoltaic market. These include Ikea, the big name in furniture, and Oscaro Power, the big name in spare parts. Feel free to consult the Oscaro Power solar panels opinion or the opinion on Ikea panels which also makes PV panels via its specialized partner.

SunPower review: verdict 

Are SunPower photovoltaic panels worth it? If you have the budget, the answer is "yes"! SunPower solar panels are worth their price, and are among the best on the market. And it's hard to find fault with them.

SunPower remains one of the world's leading players in photovoltaic panels, thanks in particular to the Maxeon range, which has cemented the American brand's status as market leader. But quality comes at a price, and Maxeon panels are the most expensive on the residential market.