Solar Panel Efficiency and Life

So, the Sun shines on Earth and in that sunshine there is energy. Plants convert that energy into mass because energy is mass. E = mc2. Energy equals Mass times a constant (which is not important here). We eat the plants for energy, or we eat animals that eat the plants. That’s how we survive.

Simple Explanation:

Well, solar panels are humans’ attempt at making “plants” that convert the Sun’s energy into energy we use – to heat, chill, or light our homes, to power our TV’s, fridges, computers, etc. Well, it’s not easy converting that sunshine into energy we can use. And as it turns out, most solar panels convert 12-15% of the Sun’s energy that falls on the panel. The Sun dumps ~1,000 W/m2 at sea level on a clear day (source: wikipedia).

The Solar Panels Don’t Matter!

Solar Panel Brand LogosStop searching for the ‘best’ or ‘most efficient’ solar panels. Stop trying to compare brands. The solar panels don’t matter. Obviously they matter in terms of the solar pv system as a whole, but which panels you use, isn’t important. Let me explain.

1.  All solar panels are warrantied for 20-25 years, which means the manufacturer guarantees the panels will still be producing at least 80% output 25 years from now. It’s the same for all brands. Don’t believe me? Ask the guy selling them.

How to Choose the Best Solar PV System

Occasionally, people ask me how to choose the best solar pv system, or the best panels. Choosing the best solar system depends mainly on your energy needs, roof space, and budget. Most people really want to know how to choose the best solar value. For example, I was asked the following question on my “Help me help you” survey:

I got bid from 2 different installers. One was SunPower panels; the other Canadian Solar. The SunPower bid (for a 5.2 kw DC system) was $21,000 and the Canadian Solar bid was $14,000 – why so far apart?

Solar Roof PosterizedGreat question. There could be many explanations why there is such a gap in the price. Generally, SunPower’s superior efficiency allows for it/ necessitates that it price its solar panels higher. (They have to pay for the best engineers to get the best efficiency, right?) Each installer may be giving you the best deal he can with both brands of panels. What you should check on both proposals is not the DC system size (in this case 5.2 kw DC), but the kilowatt-hours output. Ask your installer(s) how much energy (in kwh) each system expects to produce in the first year.

Most Efficient Solar Panels

If you have limited space and need to get the most energy for your area, then you need the most efficient solar panels for your project. People always ask me, “which panels have the highest efficiency?” or, “which solar PV panels are the best?” The truth is that solar panel efficiency isn’t as important as you might think. For most homeowners, the better question to ask is, “which panels will give me the most electricity for the best price?” You can find out how much solar might cost for your home by using our free solar calculator. But you’re here to find out the most efficient solar panels, so let’s get on with it.

The most efficient solar panel in 2016 is the SunPower SPR-X22-360 with a 22.07% panel efficiency.

Below is a solar panel comparison chart comparing the solar panel efficiency of all other modules rated at 360 watts like the SPR-X22-360. The 360 watt rating means that in strict laboratory conditions, these solar panels produce the same output. However, because solar panels vary in size, some end up being more efficient compared to others – meaning they can produce the 360 watts using less space (area).

(Updated Sept. 26, 2016)

Manufacturer ID Rating Efficiency Tier
SunPower SPR-X22-360 360 22.07% 1
LG Electronics LG360N2C-B3 360 18.94% 1
Sunpreme SNPM-GxB-360 360 18.55% 1
SunEdison SE-H360-4 360 18.40% 1
First Solar TS-360-R11-02 360 18.33% 1
Sunpreme SNPM-GxB-360 SM 360 18.28% 1
REC Solar REC360PEM 72 360 17.94% 1
Topsun TS-S360TA1 360 14.04% 4
Schuco USA MPE 360 AL 01 360 6.29% 5