One of the most portable power stations I've tested is $200 off right now

Power stations are all the rage and finding their way into homes, RVs, cars, trucks, and even tents. They are the perfect way to transport AC power to places where there isn't a convenient power socket. 

Until now, however, transporting them has meant rolling them on built-in wheels or taking the less glamorous approach of lugging them with a built-in handle. This is OK for short distances but rapidly becomes inconvenient if you need to transport the power station more than a short distance. Perhaps you're taking power to a site inaccessible by road, due to an emergency, or because you want to provide plenty of power for a group of people.

Also: The best portable power stations you can buy: Expert tested

Bluetti has the answer in the form of the Handsfree 2 -- a power station that fits into its own backpack! 

Bluetti Handsfree 2 tech specs

Battery Capacity: 512WhType: LiFePO₄ (Lithium Iron Phosphate)Life Cycles: 4000+ cycles to 80% original capacityShelf-life: Recharge to 80% every 3-6 monthsOutput Power: 700W (1,200W surge)AC Outlet x 1: 700W in totalUSB-C x 2: 100WUSB-A x 2: 15W in totalAC Input: 600W maxSolar Input: 350W maxAC Charging: 45 min to 80% / 1.3 hours to 100%Solar Charging: 2 Hours 350WCar Charging: 5.8 hours 12V / 3.1 Hours 24VPass-through Charging: YesUPS Switching Time: ≤20msWeight: About 7.5kg / 16.5lbsDimensions (L x W x D): 305 × 105 × 385mm / 12 × 4.1 × 15.2-inWarranty: 5 years 

At the core of the Handsfree 2 is a 512Wh power station, but rather than being the usual box shape, this one has been constructed into an ultra-thin form factor. However, that ultra-thin design doesn't mean that you have to compromise. 

Adrian Kingsley-Hughes/ZDNET

You're still getting a power station with an LCD panel to show you all the important information, an AC outlet good for 700W of continuous output (1,200W surge), two USB-C ports, a USB-A port, and even advanced features such as UPS-level switching and pass-through charging.

Adrian Kingsley-Hughes/ZDNET

The charge capacity is enough to recharge a smartphone about 15 to 20 times, a laptop or drone half a dozen times, and an action camera such as the GoPro about 30 times. When you get back to an AC outlet or a solar panel, the Handsfree 2 can be recharged rapidly -- 45 minutes to reach 80% capacity -- so you can get back on the move again.

Adrian Kingsley-Hughes/ZDNET

Then there's the backpack. This 60-liter backpack (or 3,600 cu in) is designed to carry not only the power station but whatever else you need, up to a maximum of 30kg. If you're not used to backpacking, let me tell you -- that this is a fair load.

Adrian Kingsley-Hughes/ZDNET

The power station fits into the back of the backpack, close to the harness, keeping the weight against your body, in the most ergonomic position. There's a side panel that enables the power station to be accessed and used without taking it out of the backpack.

There are two layers inside the backpack, one for clothes and flat items such as laptops.

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The next layer has dividers for cameras, but these dividers can be removed. 

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The backpack is constructed from splash-resistant Oxford fabric, waterproof zippers, and a rain cover that can handle medium to heavy rain. 

Adrian Kingsley-Hughes/ZDNET

The rest of the free space in the backpack can be used for other essentials such as camping or photography gear and emergency supplies.

So what's this kit like?

Starting with the power station, the 512Wh capacity checks out for me, as do the rated outputs. While a 700W AC output isn't going to handle super-heavy loads like large kitchen appliances, it's enough to handle small power tools, lights, laptop chargers, and the like.

Also: This Bluetti power station is ideal for road-tripping

The power station's display is clear and easy to read, offering an at-a-glance overview of what the power station is up to. All the controls are conveniently placed on one side of the power station so they can be accessed through the flap on the backpack. There's a handle for lifting and carrying the unit about.

As far as power stations go, it's a great unit that lives up to my expectations and the Bluetti name.

Next, the backpack.

The backpack is well-constructed from quality materials. I've seen, handled, and used a lot of backpacks over the years, and I'd say that this one rivals the best in terms of quality. It may not be quite as good as an Osprey or Mystery Ranch, but it's a well-thought-out, well-made backpack.

Also: The best power banks: Expert tested

What about comfort? This, I fear, is an area where my opinion doesn't mean much because comfort is such a subjective thing. I find the backpack reasonably comfortable: not the most comfortable, but never uncomfortable either. However, backpack comfort depends on so many things – from body size and shape to ailments and injuries – that your mileage can and will vary.

A smaller, lighter version – the Handsfree 1 – features a 268.8Wh/300W power station and a 42-liter backpack, offering a more modest amount of on-the-go power. 

ZDNET's buying advice

To be honest, I approached this product review with a skeptical eye. After all, power stations are bulky and heavy, and I didn't see the Handsfree 2 approach being all that practical. However, the design of this power station and the quality of this backpack make the Handsfree 2 a workable system for anyone who needs to lug power to places where it's not practical to take a vehicle.

Also: This Bluetti power station is ideal for road-tripping - and now it's 46% off

As a Bluetti unit, this is a quality power station constructed using quality components by a company with a track record of making exceptionally good equipment. The Bluetti Handsfree 2 is currently available for $399 from Amazon (use the $200 on-page coupon), while the Handsfree 1 is available from Bluetti for $299.

Which model should you opt for? That depends on how much power you need and how strong you're feeling.