One of the biggest myths about solar technology is that we’re always on the brink of a new major breakthrough in solar panel efficiency. This is largely the result of blogs and social media, which depend on sensational stories to attract readers, but it doesn’t exactly motivate the homeowner to go solar. “I’ll just wait for the next wave of more efficient panels,” the thinking goes.
But while improvements in panel efficiency have been made, we’re essentially using the same solar panels we’ve been using for the last 10 years, and these panels are around 10-15% efficient in terms of converting sunlight to electricity.
This is what SunPower solar panels look like once installed.
Without question, SunPower makes the most efficient solar panels, with rated efficiencies of 15-20.35%. Many find the sleek black look of these panels to be very attractive, but they come at a much higher price tag than standard models.
SunPower is followed by Sanyo panels, which are up to 17.35% efficient.
Sanyo panels: hard to tell the difference once they’re up.
The best single source of information we’ve found about this is the solar panel efficiency comparison table found on SRoeCo’s website.
Not necessarily. What most people don’t realize is that they’re smaller, so the entire solar array will take up less space. This can be good in some situations, but for most people this isn’t a big consideration.
In reality, it won’t make sense for most homeowners to go with the most efficient solar panels on the market, just like it doesn’t make practical sense for most people to have the most expensive car on the market. To be honest, we’re also talking about relatively small differences here: a spread of 15 to 17% in the case of average-vs-high-efficiency. If you get the right-sized solar system for your needs, you probably aren’t going to notice these differences anyway, except with the speed at which your solar array pays itself off (faster in the case of less-expensive panels).
Much more important than the panels you buy is the orientation of your roof, as well as obstacles (like trees) that can block sunlight. Even the slightest amount of shading on a solar array can throw efficiency numbers right out the window.
For more information on this topic, see our post on Solar Panel Efficiency.