PowerGreen 21W
Awards Editors' Choice Award Best Buy Award    
Price $84.96 at Amazon$39.99 at Amazon$35 List$49.99 at Amazon$115 List
Overall Score Sort Icon
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Pros Inexpensive, efficient, user-friendly, excels in partly cloudy conditionsInexpensive, lightweight, portable, charges quicklyRelatively lightweight for panel type, inexpensive, charges devices efficientlyLarge storage pocket, comes in multiple colors, durablePowerful, works well in partial sun, cheaper than other laptop compatible options
Cons Bulky, heaviest weightLow output power, cannot charge multiple devices at onceIneffective if relying only on solar for power, less durable than other battery packsHeavy, bulkyBulky, heavy, hard to set up, complicated adapters for laptop charge
Bottom Line For an inexpensive, easy-to-use, efficient panel the BigBlue is a no-brainer.This lightweight 13W panel is able to deliver a steady charge to a single device, but lacks in its ability to charge multiple devices at once.Our top-performing panel/battery pack.Ideal for road trips and van life, it can be selected in a color that suits your adventure style.While the X-Dragon 40W is powerful and able to charge large batteries, it is also bulky and heavy, making it difficult to transport.
Rating Categories BigBlue 28W ECEEN 13W Renogy 15,000mAh PowerGreen 21W X-Dragon 40W
Charging Speed (30%)
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9
Charge Interruption Recovery (20%)
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8
Multiple Device Charging Speed (20%)
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7
Weight & Portability (20%)
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Durability (10%)
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7
Specs BigBlue 28W ECEEN 13W Renogy 15,000mAh PowerGreen 21W X-Dragon 40W
Panel Size (watts) 28W 13W 2W 21W 40W
Weight (measured) 23.5 oz 12 oz 9.5 oz 20.3 oz 37 oz
# of USB outlets 2 2 2 2 1
Max USB Output Current (amps per port) 2 amp 2 amp 2 amps 2 amp 2.8 amps
Battery kit? No No Yes No No
Size folded 11.1" x 6.3" x 1.3" 11.4" x 6.1" x 0.6" 6.3" x 3.1" x 0.7" 11.4" x 6.8" x 1.3" 10.43" x 6.3" x 2.76"
Battery? No No Yes No No
Charge tablet? Yes Yes No Yes Yes
Charge laptop? Yes No Npo No Yes
Panel Type PET Polymer Mono-crystalline Mono-crystalline Mono-crystalline PET-Polymer
Size opened 33.1" x 11.1" x 0.2" 11.4" x 14.3 x .15" 6.3" x 3.1" 0.7" 27.6" x 11.4" x 0.2" 35.2" x 18.1" x 0.04"
Battery input (Volts / Amps) n/a n/a 5V 2A n/a n/a
Charge capacity (mAh) n/a n/a 15,000mAh n/a n/a
Charge iPhone/smartphone Yes Yes Yes Yes Yes
Direct USB Plug? Yes Yes Yes Yes Yes
Daisy Chain? No No No No No
12-Volt connection No No No No Yes
Warranty 2 years 30 day return 1 year 1 year 2 year
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