Most Efficient Rooftop Solar Panels for Homes in 2022

What's a Typical Cost To Install a new Roof? Average Price: $5,960 - $12,740
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In simple terms, the efficiency of a solar panel can be described as the percentage of incoming sunlight that gets converted into electricity. High efficiency modules tend to be more expensive, but they also use space more efficiently, generating more watts per square foot covered. This is a major benefit when you have limited roof space for solar panels, or when you want an installation to be as compact as possible.

source: SunPower

When comparing solar panels, keep in mind that efficiency is not equivalent to product quality. You can also find lower efficiency solar panels of great quality, in case you have ample rooftop space and want to reduce your total project cost. Do keep in mind that you will get fewer kilowatt-hours per square foot with less-efficient modules.

Here we will review the top 5 most efficient solar panels available in 2022, and the typical costs you can expect when purchasing them. We will also highlight other strong points they offer, in addition to high efficiency. The most efficient solar panels that are commercially available range from 21% to 23%, with SunPower leading the way at 22.8% conversion efficiency.

Before covering each brand in detail, here is a summary table with their efficiency ratings, wattages, and typical costs according to EnergySage and RoofingCalc.com:

Brand Product Line Wattage Efficiency Average Brand Price (All Products)
1. SunPower M-Series 420W Up to 22.8% $3.12-$3.74 / watt installed
2. LG Solar NeON R 405W Up to 22.3% $2.46-$3.38 / watt installed
3. REC Alpha Pure R 430W Up to 22.3% $2.32-$3.10 / watt installed
4. Panasonic EverVolt 380W Up to 21.7% $2.77-$3.90 / watt installed
5. Silfab Elite 380W Up to 21.4% $2.45-$3.09 / watt installed

Photovoltaic cells of even higher efficiency have been developed under laboratory conditions, but they are still experimental products. Even if you can purchase these PV cells somehow, keep in mind that most solar installers are not familiarized with them.

Traditional solar panels are the recommended option – you can get a professional installation, solid warranty coverage, and easy access to technical support if anything goes wrong.

1. SunPower Maxeon M-Series

Maximum Efficiency: 22.8%

Power Rating: 420W

Average Price (According to EnergySage): $3.12 to $3.74 per watt installed

The SunPower Maxeon M-Series is the most efficient PV module in the market as of July 2022. This product is around 10% larger than the typical home solar panel, having 66 PV cells instead of the traditional 60-cell design. According to their specification sheet, Maxeon M-Series modules are 73.7” tall and 40.6” wide.

For comparison, 60-cell modules have typical dimensions close to 66” x 40”, which means they have roughly the same width but around 10% less height.

The Maxeon M-Series is an AC solar module, which means it operates with a microinverter and you get AC power directly from each panel. Most home solar systems use DC modules, which are wired together in circuits and connected to a string inverter.

The microinverters on SunPower M-Series panels are factory-integrated, which means your solar installer will not waste time connecting one microinverter to each module. Other product features include:

  • Operating temperature range: -40°F to +185°F (-40°F to +85°C)
  • Temperature coefficient: -0.29% per °C
  • Product Warranty: 25 years
  • Power Production Warranty: 25 years
  • Capacity After 25 Years: 92% of initial electricity output

SunPower also gives you the option of using a traditional system layout with the Maxeon A-Series, which are DC modules designed to operate with a string inverter. They offer an efficiency of up to 22.5%, which is only slightly lower than the M-Series efficiency. Both product lines have the same operating temperature range, temperature coefficient, and warranty term.

2. LG Solar NeON R

Maximum Efficiency: 22.3%

Power Rating:  405W

Average Price (According to EnergySage): $2.46 to $3.38 per watt installed

LG Solar and REC are tied as the 2nd most efficient solar brands in the market as of 2022, surpassed only by SunPower. The LG Solar NeON R uses a 60-cell design like most residential modules, with a height of 1,740 mm (68.5”) and a width of 1,042 mm (41.0”). The NeON R also offers the following features:

  • Operating temperature range: -40°F to +185°F (-40°F to +85°C)
  • Temperature coefficient: -0.29% per °C
  • Product Warranty: 25 years
  • Power Production Warranty: 25 years
  • Capacity After 25 Years: 92.5% of initial electricity output

The NeON R modules have a DC design, which means they are wired in circuits with standard MC4 connectors, and they use a string inverter. LG also offers the NeON R ACe module with a built-in microinverter, which means you get AC power directly from each panel.

Compared with the traditional NeON R module, the ACe version has a slightly lower efficiency of 21.8%, and also a slightly lower power rating of 395 W. The operating temperature range, temperature coefficient and warranty conditions are the same for both products.

SunPower and LG Solar offer similar products, which are available in both DC and AC versions. Both brands offer an excellent temperature coefficient of only -0.29% per °C and a 25-year product and power output warranty.

SunPower has a slightly superior efficiency, but this also comes at a higher price. Both brands can maximize the productivity of your available roof space, having the highest and 2nd highest efficiency in the solar industry.

Just keep in mind that the SunPower M-Series modules are slightly larger due to their 66-cell design, while the LG Solar NeON R uses a more compact 60-cell design. There may be cases where the LG Solar module fits in a roof section where the SunPower module does not.

3. REC AlphaPure

Maximum Efficiency: 22.3%

Power Rating: 430W

Average Price (According to EnergySage): $2.32 to $3.10 per watt installed

REC Alpha Pure R solar panels are characterized by their sleek design. Unlike traditional 60-cell panels, which have clearly visible divisions between PV cells, this product series has a uniform black surface. The module has a height of 68.1” and a width of 44.0”.

Alpha Pure R solar panels are composed of 80 half-cut bifacial cells, which means they can generate electricity with sunlight reaching both sides of the module.

When used in a rooftop installation, half-cut bifacial cells benefit from both, the sunlight reaching them directly, and the sunlight reflected by the roof towards their underside. Thanks to this design, Alpha Pure R modules are tied in second place with the LG Solar NeON R modules at 22.3% conversion efficiency.

In terms of temperature performance and warranty coverage, REC Alpha Pure R models have the following specifications:

  • Operating temperature range: -40°F to +185°F (-40°F to +85°C)
  • Temperature coefficient: -0.26% per °C
  • Product Warranty: 25 years
  • Power Production Warranty: 25 years
  • Capacity After 25 Years: 92% of initial electricity output

REC offers a slightly better temperature coefficient compared with SunPower and LG Solar. Both of these brands lose 0.29% performance per °C degree of temperature rise, while the REC modules only lose 0.26% per °C. — This may seem like a small difference, but it adds up when you consider that solar panels are under direct sunlight for several hours each day.

A temperature rise of 20°C would cause a 5.8% performance drop in the other two brands, while REC suffers a smaller 5.2% drop.

REC offers another version of this product, called Alpha Pure. This module has a slightly lower power rating of 410 W, and 22.2% efficiency. These modules are also larger than the Alpha Pure R series: they have 132 bifacial half-cells, a height of 71.7”, and a width of 40.0”. Both product lines have the same temperature performance and warranty conditions.

4. Panasonic EverVolt

Maximum Efficiency: 21.7%

Power Rating: 380W

Average Price (According to EnergySage): $2.77 to $3.90 per watt

The Panasonic EverVolt module is characterized by its compact design and high efficiency, and its dimensions are typical of a 60-cell residential module: a height of 67.75” and a width of 40.0”.

However, the EverVolt series uses 120 half-cells to achieve a higher efficiency, which is the 4th highest in the industry as of July 2022. The brand is also characterizes by its superior temperature performance and excellent warranty coverage:

  • Operating temperature range: -40°F to +185°F (-40°F to +85°C)
  • Temperature coefficient: -0.26% per °C
  • Product Warranty: 25 years
  • Power Production Warranty: 25 years
  • Capacity After 25 Years: 92% of initial electricity output

Panasonic also offers the EverVolt Black series, which has a smooth and uniform surface without visible divisions. You get a slightly lower efficiency of 21.2%, but Evervolt Black is a great option if you prefer solar panels without visible divisions between their PV cells.

Panasonic and REC solar panels are comparable in terms of their temperature performance, losing 0.26% output per °C. SunPower and LG solar panels are slightly more affected, losing 0.29% of their output per °C, but all four products have an excellent temperature coefficient. There are solar panel brands in the market that lose up to 0.40% of their output per °C of temperature rise.

5. Silfab Elite

Maximum Efficiency: 21.4%

Power Rating:  380W

Average Price (According to EnergySage): $2.45 to $3.09 per watt

Silfab Elite modules have a 66-cell design and a uniform black surface, 70.67” tall and 38.98” wide. This product is a great option for homeowners who don’t like solar panels with visible divisions between PV cells. Other than their high conversion efficiency of 21.4%, Silfab Elite solar panels offer the following features:

  • Operating temperature range: -40°F to +185°F (-40°F to +85°C)
  • Temperature coefficient: -0.377% per °C
  • Product Warranty: 25 years
  • Power Production Warranty: 30 years
  • Capacity After 25 Years: 85.1% of initial electricity output (82.6% after 30 years)

Compared with other solar panels covered in this list, the Silfab Elite module has one notable advantage and two weaknesses. Silfab offers a 30-year power output warranty, which is among the longest in the solar industry, while most competing brands offer a 25-year warranty.

The guaranteed power output after 25 years is 85.1%, while the other four brands discussed above offer 92%. In other words, Silfab offers a longer warranty than competing products, but the percentage of initial output covered by the warranty is less.

Silfab Elite solar panels also have a temperature coefficient of -0.377% per °C, which means they suffer a 7.54% performance drop with a 20°C temperature rise. The other four modules in this list have smaller temperature coefficients of -0.26% or -0.29% per °C, which means a 20°C rise has an impact of 5.2% or 5.8% (depending on the brand).

Silfab is an excellent brand overall, but you might get a slightly lower performance if you live in a place with hot weather.

Answering Key Question: Do I Need High Efficiency Modules?

The main benefit of high efficiency solar panels is generating more kilowatt-hours per square foot covered. This is a major advantage when your roof space is limited, or when you want to use the smallest possible roof area.

However, solar panels with lower efficiency can also a viable investment if you make sure they are reliable. Regardless of module efficiency, make sure you check all other specifications, including temperature coefficients and warranty terms.

What's a Typical Cost To Install a new Roof? Average Price: $5,960 - $12,740
See Costs Near You

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