As with all forms of renewable energy and electricity generation generally, solar companies are continually looking for ways to increase solar panel efficiency. Producing more electricity per square foot of solar panels makes your solar power system both more cost effective and more sustainable, as it reduces the amount of raw materials required for each system.
The Race to the Most Efficient Solar Panels
Who Makes The Most Efficient Solar Panels Today?
Most standard efficiency solar panels range from an average of 14% to 17%. The largest manufacturers of standard efficiency panels globally include Trina Solar, JinkoSolar, and Canadian Solar. U.S.-made solar standard efficiency panels are available from Mission Solar,
Commercially available high-efficiency solar panels range from 18% to 22%. The solar companies who make high-efficiency panels include SunPower, Panasonic, and LG. Some Sunpower panels have been rated at 24%.
Manufacturer |
Solar Panel Model |
Maximum Rated Efficiency* |
SunPower |
X-Series |
Up to 24.1% |
SunPower |
E-Series |
Up to 20.4% |
LG |
NeON 2 |
Up to 19.8% |
Panasonic |
HIT N330 |
Up to 19.7% |
Upsolar |
Mono 60 |
Up to 19.7% |
Hanwha |
Q.Peak Duo |
Up to 19.3% |
Solaria |
PowerXT |
Up to 19.3% |
Trina Solar |
ALLMAX M PLUS |
Up to 19.2% |
Sunpreme |
Maxima |
Up to 19.1% |
Silfab Solar |
SLG-M |
Up to 19.0% |
RECOM |
Black Panther |
Up to 18.98% |
Heliene |
60M |
Up to 18.9% |
Itek Energy |
SE 60 |
Up to 18.78% |
JA Solar |
JAM6K-72-360PR |
Up to 18.57% |
Yingli Solar |
YGE 60 Series 2 |
Up to 18.5% |
SolarTech Universal |
Quantum |
Up to 18.4% |
Renogy |
Eclipse |
Up to 18.35% |
SunSpark |
Mono |
Up to 18.2% |
Mission Solar |
MSE PERC 60 |
Up to 18.05% |
CanadianSolar |
MAXPOWER CS6U |
Up to 18.0% |
First Solar |
Series 6 |
Up to 18.0% |
SolarWorld |
Sunmodule Plus |
Up to 17.89% |
Centrosolar |
C-series |
Up to 17.8% |
Suniva |
Optimus |
Up to 17.57% |
Winaico |
WSP-P6 |
Up to 17.46% |
Motech |
XS60 |
Up to 17.4% |
Axitec |
AXIpower |
Up to 17.21% |
Gintech |
Mono 60 |
Up to 17.2% |
REC |
TwinPeak 2 |
Up to 17.1% |
SunTech |
STP330 |
Up to 16.9% |
China Sunergy |
Poly 325W |
Up to 16.78% |
Phono Solar |
Diamond Series |
Up to 16.75% |
Amerisolar |
Monocrystalline |
Up to 16.69% |
JinkoSolar |
JKM270P-60 |
Up to 16.5% |
Sharp |
NDAH320 |
Up to 16.5% |
Seraphim |
SRP-6PA |
Up to 16.49% |
Kyocera |
KT Series |
Up to 16.1% |
ReneSola |
Virtus II |
Up to 16.0% |
Mitsubishi Electric |
MLE Series |
Up to 15.7% |
Grape Solar |
GS-STAR-100W |
Up to 14.63% |
Stion |
Elevation 4 |
Up to 14.3% |
* According to the manufacturer’s published product data sheet as of June 2018
What Determines Solar Panel Efficiency?
The primary determinant of solar panel efficiency is the materials used in the panel. The most efficient solar panels are made from monocrystalline silicon. Other materials used in the panel also make a difference, such as the material and design of the panel’s conductive metal foundation, the type of glass used on the front of the panel, and the interconnects between the cells. If you see thin lines of metal ribbon on the front of a cell, it is subject to increased breakage compared to a solar panel with a copper-backed foundation.
There are limits to the maximum potential efficiency of solar cells. The theoretical limit of efficiency under ideal conditions is estimated to be up to 85%. A study last year demonstrated that a solar panel achieved 44.5% efficiency by layering different materials over a single panel surface to enable it to capture a broader range of the light spectrum.
Solar radiation in different parts of the country, roof pitch, and azimuth (horizon angle), temperature all affect solar panel efficiency, and there may be other energy losses throughout the system related to the length and type of the cabling, voltage limits, and inverter efficiency.

Efficiency Beyond The Panel Rating & Troubleshooting Generation Issues
Keep in mind that beyond a solar panel’s rated efficiency, there are some practical real-world conditions that contribute to variances in efficiency for a particular solar panel over time, including cloud cover, sun intensity during different seasons, and humidity.
Lower than expected solar generation could be related to one of these factors rather than indicating a problem with your system. Here are a few steps you should take if you notice that your solar production is lower than normal:
Check your monitoring system.
If you have panel-level monitoring (made possible through integrated microinverters), you may be able to isolate the issue to a single panel or inverter that could require repair or replacement.
Check the weather.
Keep in mind that rainy or cloudy weather can affect your system's generation. If you have noticed more inclement weather days than normal (compared to recent months or the previous year), that may be the cause of reduced energy production rather than any issue with the system itself.
Clean your panels.
It is always a good idea to visually inspect your solar array periodically to look for debris or an accumulation of dirt or dust, and you should clean your panels once or twice a year with water and a soft cloth or sponge.
Call your installer or the manufacturer.
If your system is underperforming and none of these factors seems to the cause, contact your solar installer or the solar panel manufacturer for their assistance.

Get The Most Efficient Solar Panels On Your Home
If you're considering going solar, we recommend using the most efficient solar panels on the market, available from SunPower.
Freedom Solar is proud to be the first and only SunPower Master Dealer in Texas. SunPower by Freedom Solar was recognized as the 2017 "Residential National Dealer of the Year" and "Residential Regional Top Producer of the Year" for consistently putting customers first, demonstrating exceptional industry knowledge and leadership, and installing more residential solar than any other dealer in the central U.S.
To request a quote on SunPower® solar panels for your home, call us at 877-969-1946 or contact us online:
Begin Your Free Consultation
By clicking “Contact Me” you authorize Freedom Solar to call you and send you pre-recorded messages and text messages at the number you entered above, using an autodialer, with offers about their products or services, even if your phone number is a mobile phone or on any national or state "Do Not Call" list. Message and data rates may apply. Your consent here is not based on a condition of purchase.