Solar Charger Review: Opteka BP-SC4000

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Summer means more time being active outdoors, which is great for your body, but can be a hassle for keeping your gadgets charged.  A lack of outlets in the great outdoors may have you looking at solar chargers, but are they a successful substitute for an AC plug?

Many people assume that a solar charger can supply the same amount of power as your home outlet by simply basking in the sun.  However, this would require a very large solar cell and wouldn’t be practical for portability.  Many solar chargers available today have a built-in battery reserve and are made to store the sun’s rays over the course of several days.

The smarter our smartphones get, they require more power and larger batteries to keep up with our apps.  I checked out the Opteka BP-SC4000, which boasts a 4,000mAh battery. This sounds like it should be able to power the iPhone 4S’ 1,432mAh battery several times over.  In practice, this fully charged charger was only able to replenish my phone one time, with just a little power leftover to spare.

Charging the Opteka by solar does indeed take a few days of clear skies and sunshine.  Even then, I’m never able to get the Opteka to full capacity: I’m only ever able to reach 3 out of the 4 bars on the built-in battery meter.  Thankfully, the Opteka can also be fully charged by mini-USB in a few hours.


  • Large capacity battery, although the 4,000mAh rating is questionable.
  • Built-in LED battery level indicator, which also shows a cool animation effect to let you know you have enough sunlight to charge.
  • Provides a standard USB port for charging and includes several different tips for all your gadgets (but you can also use your own USB cable).


  • Requires several days of sunlight, and then only charges to about 75% capacity max via solar.
  • The plastic housing doesn’t seem very durable for dangling it off your backpack while hiking.

So does that mean the solar charger is completely useless?  Nope, it just requires a different use.  Charge the Opteka completely with regular AC power before heading out, then use the solar panel to “top-off” your charge throughout the day (or at least slow-down the discharge while powering up your devices).  For example, this can come in handy for a day at the beach where it will get plenty of sunlight, but only plan on one full recharge for your smartphone.


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