Getting out into the great outdoors can be a fantastic stress reliever, but one big problem these days is that you generally have to leave your gadgets behind. But what if you could get instant power anywhere, with just water as fuel; no electrical socket, sun or wind required?
Enter the PowerTrekk hydrogen fuel cell charger.
What is a fuel cell?
The PowerTrekk is being marketed by myfc as the 'world's first portable fuel cell charger'. A fuel cell is an electrochemical device that turns chemical energy stored in a fuel, be it methanol, gas, petroleum, or any energy-rich compound, into electrical energy.
Of course, in this case we're talking about hydrogen, and the chemical energy locked up in water.
Hydrogen fuel cells essentially create water, reacting pure hydrogen gas with oxygen from the air to produce good old H2O. During the reaction, chemical energy from the formation of chemical bonds between one oxygen and two hydrogen atoms is released.
The fuel cell harnesses that energy to push ions from one electrode to another, a lot like a traditional battery, generating a flow of electrons and therefore electricity in the process. That electricity can then power whatever you happen to have hooked up to your fuel cell.
The problem is that hydrogen isn't the most stable of elements, and is highly combustible, so it's dangerous to store in a pure, gaseous form. The PowerTrekk, therefore, uses another chemical reaction first to generate the fuel we need, one with water and sodium silicide, which produces aqueous sodium silicate and the all-important pure hydrogen gas.
The hydrogen then passes safely up into the fuel cell to react with the oxygen in the air, producing water, electricity, and a little heat. So, in essence, the PowerTrekk turns water into hydrogen and then back into water again, releasing energy in the process.
Powering up your gadgets
So, we know how it works in theory, but how does it perform in practice? The PowerTrekk has three components: a tiny water reservoir; a puck which contains the sodium silicide, and the green plastic fuel cell top.
Simply fill the tiny tank up with water, slap a puck in the slot, and lockdown the fuel cell to pierce the puck and start the reaction generating electricity. It starts up pretty quickly, and can immediately start charging anything hooked up to the USB port.
Of course, when you punch a hole in the puck and start the chemical reaction, there's no way to turn it back off, so the PowerTrekk has a built-in lithium-ion cell too, which can be charged from the fuel cell when nothing's hooked up to the USB port.
The hybrid battery- fuel-cell system also has the added benefit of being able to augment the 2W- charge, provided purely by the 5.6 Watt hour fuel cell, up to the 2.5W normally demanded by your average smartphone. You can always charge the internal battery via microUSB, so you don't even need to initiate the fuel cell if you're just topping up your phone's battery, but where's the fun in that?
Each puck is good for around two full charges of a phone battery.
Using it is straightforward; charging LEDs on the side show you the state of the internal battery, and there's a button to initiate charging over the USB port. A green-glowing emblem of the fuel cell lights up on the side when the fuel cell is producing electricity, and flashes when the puck is nearing depletion. It will turn red and buzz if there's a problem, like the internal battery is fully charged and you haven't hooked anything up to the USB port.
The pucks are one-time use and disposable. During operation the fuel cell gives off a little heat, but nothing more than a smartphone that gets warm while playing a game. The biggest downside to the PowerTrekk is, however, that you have to keep the thing upright and clear of obstructions while in operation.
That means you can't just fire up the fuel cell and sling it in your bag to charge whatever you need. It also emits quite a pungent smell, and buried deep in the safety instructions it tells you that you must use it in a well-ventilated area. But, let's face it -- you're not going to be using this thing unless you're out in the great outdoors anyway.
Once the puck nears depletion, you have to wait for all the hydrogen to be released before you can take the fuel cell off and dispose of the puck, which in our testing took quite a while. The puck can also get quite hot so you have to wait for it to cool before chucking it in the trash. However, we were only given review samples with 'limited capacity', which probably means your mileage will be different.
It's quite pricey, at around the $230/£150 mark for the fuel cell, with a pack of three pucks running you about $12/£8, but it's light, rugged, and will charge more or less anything that has a USB plug instantly with just the power of water, anywhere.
The PowerTrekk is a useful piece of kit if you happen to be journeying out into the wilderness anytime soon, and marks one of the first consumer-available steps towards a hydrogen-powered future.