Choosing the best solar panels
November 15th, 2013 / By: Ed Sztukowski
4 things to consider before commiting
While you're busy thinking about which solar installer to work with, it's easy to forget another important aspect of the process: the solar panels themselves.
Solar installers not only differ in reliability, but also in the kinds of solar panels they offer. To ensure you're getting the best deal with solar, be sure to ask about the actual panels in addition to typical questions about the installer. In particular, focus on some of the following characteristics:
- -- Brand reputation
- -- Type of solar cell used
- -- Size and cost
- -- Conversion efficiency
1) BRAND REPUTATION
Much like computers, televisions, and other electronics, certain brands of solar panels consistently earn high grades. A brand's reputation typically centers on their history of customer service (warranties, etc) and panel performance (efficiency).
While we can't tell you exactly who to trust exactly, you could check to see what manufacturers are popular with other consumers. According to the California Solar Initiative, the most popular solar panels California are made by:
- -- Sunpower
- -- Yingli Solar
- -- Sharp
- -- Suntech Power
- -- Kyocera Solar
When deciding between solar installers, make sure to ask what brands of solar panels they offer. Then, explore how those brands differ from each other by examining the solar cells used in production, the cost per watt, and conversion efficiency.
2) TYPE OF SOLAR CELL
There are three major types of silicon cells used to create panels:
Monocrystalline is the highest quality of solar cell. It is cut from a single cell of pure silicon, which allows them to more efficiently convert the sun's energy to electricity. You can tell if a panel uses Monocrystalline silicon cells if it appears completely smooth and black.
Polycrystalline cells are made up of multiple silicon cells fused together. This makes them slightly less efficient than Monocrystalline cells, but more affordable as well. Typically, these kinds of solar panels appear bluish in color.
Thin-film Silicon cells make up the cheapest and least efficient solar panels. To create thin-film panels, manufacturers spray a layer of silicon onto a substrate. Thin-film solar panels may appear more flexible than other kinds.
3) SIZE AND COST
How much a solar panel costs is tied into several aspects, but size is by far the most important.
If you examine some different kinds of solar panels online, you'll notice terms like "100-watts" or "250-watts." These are important, because solar panels are typically priced per watt. In California, the average price-per-watt for a solar panel is currently $5.55.
When you're gathering information from solar panel installers, make sure to ask them what wattage their solar panels are rated. A great follow up question to ask is how efficient the panels are.
4) CONVERSION EFFICIENCY
A solar panel's ability to convert sunlight to electricity relies on how efficient it is. Unfortunately, not all solar panels are created equally, with some performing much more efficiently than others.
Solar panels have grown increasingly efficient, with the first panel only converting 1% of the suns energy to electricity. Today, most solar panel efficiencies range from 19% to less than 12%.
So in a bad scenario, you could buy a 250-watt solar panel and find it actually creates less electricity than a more efficient 200-watt solar panel.
Making sure to purchase efficient solar panels lets you lower the number of panels you need to buy, saving you money. Currently, Sunpower creates some of the most efficient panels, with one model reaching 19%.