The Eton BoostTurbine 4000 is a unique portable charger. It's half everyday battery pack that can charge many modern smartphones, and half emergency power backup, thanks to its hand crank that lets you harness your elbow grease to power your dead iPhone. That makes it an ideal backup battery for powering your gadgets away from home, and helps you get power when there is no other power source, such as during a blackout, while you're camping, or if you've traveled to a remote area.
Most emergency backup power sources I've come across, like this Ambient Weather model and this one from Eton, also include a radio and flashlight, which can be handy during an emergency or power outage. As such, I'd probably stick with one of those products in a natural disaster instead of the BoostTurbine.
I would use the $79.99 BoostTurbine when after a long day my smartphone is dead and I need to call a cab. Even if it doesn't have any juice, I could spend a few minutes cranking it to build up enough energy in its battery to power up my gadgets.
The BoostTurbine is roughly the size and weight of the type of power brick found on a power cable for a game console or laptop. It sports a smooth brushed-aluminum case with sharp edges on the bottom.
On the back is the plastic crank that snaps into the main body for storage. The crank has a firm hinge that moves smoothly and keeps the crank in place. That's a plus, because I've used crank chargers where the crank moved around a lot while I turned it, making it hard to get into a momentum and charge the battery.
The hand crank rotates both clockwise and counterclockwise, and while you turn it, the crank makes a loud whirring noise that's typical of other hand-crank gadgets.
Along the top of the BoostTurbine, there is a standard USB and a Micro-USB port, a power button, and LED indicator lights (more on those later). The device comes with one Micro-USB-to-USB cable, which you use to charge your gadgets. You can also charge the BoostTurbine itself by connecting the cable to your computer's USB port and plugging the Micro-USB end into the charger's corresponding port.
Eton calls the device pocket-size, but it's a bit clunky for that description. It's too large to fit in most guys' jeans pockets, so I can't see this being something you take with you everyday. It will easily slip into a purse or laptop bag, but at 9 ounces, you'll notice the extra weight.
Charging the BoostTurbine
You can charge the BoostTurbine 4000 two ways, by plugging it into a power source, such as a computer or wall outlet adapter, with the included cable, or by using the hand crank. On separate occasions I used my computer's USB port and a typical USB-to-wall-outlet adapter from a smartphone charger to get the BoostTurbine to a full charge.
It's worth noting that you can use the cable to charge any gadget that has a Micro-USB port. To charge an Apple device, you'll need to use your own 30-pin or Lightning cable and plug the USB end into the port on the BoostTurbine.
When you turn the hand crank, you're creating kinetic energy that is stored in the internal battery as reserved power. As soon as you connect your smartphone to the BoostTurbine, your phone will transfer that stored energy into its own battery. Eton says that 1 minute of cranking will give you 4 minutes of talk time. You need to rotate it about one or two revolutions per second to generate enough energy to charge the battery.
Though the BoostTurbine has four LEDs that lit up to show the battery's level when I turned the crank, it was hard to tell exactly how much power I was creating. For instance, if the battery is at 50 percent, two LEDs will light up solid and a third will blink, indicating that you're charging the battery. I never got the next light to come on, as my hands got tired after a few minutes of continuous cranking.
Eton notes that it takes 4.5 hours to get the BoostTurbine to a full charge while plugged into a power source. In my testing, it took just around 40 minutes for the device to go from two lights to three while plugged into my computer via USB, so that's a plausible time frame.
Charging your gadgets
The device gets its name from its internal 4,000mAh lithium ion battery. While that power capacity is lower than competing portable chargers', the BoostTurbine still provides enough power to charge nearly any smartphone once or twice on a single charge.
I tested the BoostTurbine's charging capabilities on a completely dead Nokia Lumia 925. After connecting it to the phone, it took around 5 minutes for the charger to give the phone enough power to turn on. I was then able to use the Lumia 925 to make phone calls and check e-mails while it continued to charge.
Two hours later, the phone had 50 percent battery charge and the BoostTurbine had gone down to only 75 percent.
Though the portable charger doesn't have enough juice to fully charge a fourth-generation iPad, which has an 11,666mAh battery, I was able to get some power. My iPad went from 80 percent to 90 percent charge in around 20 minutes, but the BoostTurbine was nearly dead afterward.
Rechargeable batteries, like the one in the BoostTurbine, have a tendency to lose the ability to hold a charge over the years. While I didn't notice any issues in my testing, it's worth remembering that batteries like this don't last forever.
Given that the BoostTurbine 4000 is heavy and clunky, it's not the most portable gadget charger on the market. And even though it has a hand crank for when the power goes out, it's not the most ideal emergency device either because it's missing a flashlight and radio. Still, with 4,000mAh of power, the BoostTurbine will save your phone when it runs out of battery life.
At $80, the BoostTurbine is pricey compared with most other portable chargers out there, even ones that have more power capacity. For your everyday power needs, you're better off looking at the cheaper MyCharge Peak 6000, which has a bigger battery as well. If you need something to keep you up and running during a power outage, camping trip, or disaster, the BoostTurbine 4000 is a decent choice, if you don't mind turning the crank for a while.