Standard vs. High-efficiency solar panels

Already made the decision to go solar? Well that’s the easy part, now which panels do you select? There are over 300 manufacturers of solar panels available to you, all of varying efficiency, size, production output, warranty, and aesthetics. Ironically, most installers choose to only work with one or two panel brands. To ensure you are getting the best panels for your home and energy usage, you will need to weigh standard-efficiency against high-efficiency and consider all benefits.

There are many differentiators between standard and high-efficiency panels, but for simplicity, most homeowners consider production and their respective price. Standard efficiency panels are considered to be around 14% – 17% efficient and include brands like Canadian Solar and SolarWorld. High-efficiency panels surpass 19% efficiency and include the brand SunPower which holds more than 200 patents. If shade or limited roof space is jeopardizing how many panels you can place on your roof, then a higher efficiency panel is ideal because they can produce the same amount as a conventional panel system but will need fewer panels to do.

A more efficient panel brings more production, however, more production comes at a higher cost. SunPower panels will produce significantly more energy during their 25-year warranty than conventional panels, about 20% more energy. SunPower’s Maxeon® solar cells allow their panels to only degrade at about 0.1% – 0.25% per year. Standard panels will degrade at about 0.5% per year. This means that by the 25th year, high-efficiency panels will still produce an output of about 93%, while standard panels will produce about 88%. Ultimately, this means 20% more energy over the first 25 years with high-efficiency panels.

Panel Type Standard Efficiency High Efficiency
Sample Brands Canadian Solar, SolarWorld SunPower
Panel Efficiency 14% – 17% per sq. ft. 19%+ per sq. ft.
Degradation (per year) 0.5% 0.1 – 0.25%
System Output

(after 25 years)

88% 93%
Avg. price (per watt) 80¢ – $1.10 $1.60 – $2.10
Ideal scenario Lowest cost Most production and

Limited roof space


When it comes to the cost to justify their production, on average, SunPower panels are about $1.00 more per watt than conventional panels. If you’re looking to go solar at the lowest cost possible, then standard-efficiency panels are your answer. A lower start-up cost also allows more budget in case you need to expand your system. However, if sheer production is what you’re looking for, high-efficiency SunPower panels are the only solution. Explore all options, make sure you choose the best fit for your home, usage, and budget.