The Best Photovoltaic Solar Panels

Sanyo HIT Power N Series

• The most efficient photovoltaic solar panel available to the public in 2011 is the Sanyo HIT Power N Series. Sanyo has been working to perfect its technology since the mid-1970s. The cells are hybrids of monocrystalline silicon, surrounded by ultra-thin amorphous silicon layers. This technology is unique to Sanyo. The efficiency of Sanyo panels means a Sanyo panel produces more electricity than other manufacturers' panels of the same size. The Sanyo panel is 31.4 by 62.2 inches, generates 220 watts at 5.65 amps, and has a cell efficiency of 19.8 percent. One of the unique features of these panels is that their efficiency increases as the surrounding temperature rises. They are made in California and Oregon.

SunPower E19 Solar Panel

• The SunPower E19 Series solar panels are the second-most efficient panels as of 2011. They are 31.4 by 61.42 inches, produce 238 watts at 5.88 amps, and have a cell efficiency of 19.1 percent. SunPower uses a black monocrystalline solar cell. The company combines these cells with an al- black panel to visually blend into a roof in a more appealing way. Under SunPower's distribution model, you must purchase and install the panels via one of their certified partners to maintain their warranty. This reduces your ability to negotiate price, because their dealer network will not quote against one another. The number of dealers also is limited in parts of the United States and Canada.

Trina Solar Quadmas Solution

• Trina Solar was founded in 1997 and has since grown dramatically, delivering 399 megawatts of panels in 2009. Their most popular panel is the TSM-PA05, because is has low cost to kWh ratio. This means the panels pay for themselves faster. This panel is 39.05 by 64.95 inches, produces 240 Watts at 7.89 amps and has a total module efficiency of 14.7 percent.

Siliken SLK60P6L

• The Siliken SLK60P6L has a module efficiency up to 15.1 percent. It produces 245 Watts and is 38.97 by 64.57 inches in size. The cells use a polycrystalline technology and are designed for grid-tied applications. They are guaranteed to produce 90 percent of rated power in 10 years and 80 percent in 25 years.