About 20 years ago, when I was going through something of a mid-life crisis, I bought myself a Subaru WRX performance sedan. It was a 1998 model and it was a deep metallic green colour. If you didn’t know anything about the WRX, it looked like a very ordinary small car with a subtle body kit bolted to it, some nice wheels and a ridiculous-looking scoop on the bonnet. Inside wasn’t much more exciting. In fact, it was very basic. You would get more features in a Toyota Corolla of the day. But the Rexy was certainly no Corolla when you put the foot down.
Under the scooped bonnet lay one of the motoring industry’s best engines ever. It propelled the Rex from zero to 100km/h in less than six seconds and it would go around corners like it was on rails. It was exhilarating to drive.
Why am I telling you this story? The point is that my WRX may have been short on bells and whistles but it had it where it counted, making it the best car I’d ever driven. It was the perfect example of a manufacturer keeping things simple to make a product that was very, very special.
Such is the case with Bluetti’s latest portable lithium power station, the AC50B. In contrast to the general trend for manufacturers to add more and more features to their products, the AC50B would seem to be a step back, even by Bluetti’s standards. But after putting it through its paces, the AC50B surprised me with its overall performance and versatility.
BLUETTI SPECS
At the heart of the AC50B is a 448Wh LiFePO battery and a 700W 240V inverter. It has a single 10A 240V outlet, two 65W USB C and one 15W USB A outlets, and a single 12V cigarette lighter output. It has a single DC input for both auto and solar charging, and a 240-volt input on the side for AC charging. That’s it. There’s no wireless charging station, no splash-proofing, minimal dust-proofing and no 15A mains outlets.
There are just three buttons on the front. One to power the unit, one to power the DC outputs and one to power the AC outlets. The digital display is functional and tells you all the important information you need. That’s about it!
Fortunately, it’s not all 1990s sedan simplicity. The Bluetti AC50B is compatible with Bluetti’s excellent smart device app, which offers full control over all the AC50B’s features, including setting the AC charging mode, remote switching of the DC and AC outputs, adjusting the Eco output settings and putting the inverter into Power Lift mode to boost the inverter capacity to an impressive 1000W.
The app also allows you to do firmware updates and gives you quick access to Bluetti support and to Bluetti’s user forum. The graphic shows the amount of charging watts coming into the unit as well as power out wattage. It’s a great app that will satisfy the geek in any owner.
Other features include an MMPT solar controller that can accept panels up to 200W, 580W maximum AC charging, pass-through charging and a UPS switching time of less than 20 milliseconds.
Now let’s get to some of the features that I reckon make the AC50B stand out.
TRULY PORTABLE
The AC50B is small for a power station of this capacity. Measuring just 280x200x220mm and weighing in at just 6.7kg, it is smaller and lighter than the Bluetti AC60 we reviewed in December last year. You should have no problem storing the AC50B anywhere in your car, camper or caravan.
The light weight combined with the integrated carry handle makes moving the unit around your campsite effortless. It is very surprising how portable this unit is given its capacity.
PEDAL TO THE METAL
All of this would be pretty meaningless if the Bluetti AC50B didn’t perform as expected, and that meant delivering the run time its 448Wh battery promised.
To find out, I put the AC50B through a series of tests, running various devices continuously until the unit shut down, measuring the time it took to flatten the battery and calculating if that met expectation.
The first test was to power the Waeco 40L fridge in my car. I estimated the fridge, powered by the 240V outlet, should run for around 18 hours. After 24 hours, it was still running with one per cent indicated remaining battery capacity. That was impressive enough but it was the next test that really surprised me.
I ran three 240V lights with a total continuous and steady output of 58W. The display showed the approximate run time to be just over six hours. This was very unusual as it was less than the time I would have expected for that load. I let it run anyway to see what would happen. After eight hours, the lights were still on and the battery capacity was down to five per cent indicated. One and a half hours later, the battery finally went flat and the inverter turned off. That equated to 551Wh, around 20 per cent more than the battery’s stated capacity.
That was a remarkable result. In fact, it was too good, so I did the same test again and I got a very similar result. This was shaping up to be a very interesting test indeed. I tried running other, higher wattage loads of varying capacities and they were more consistent with Bluetti’s specification.
Importantly, none of the test results were under specification. Anyone familiar with portable lithium power stations will know that when testing the capacity of the battery using 240V loads, you can expect to account for inverter overheads of around five or 10 per cent. This doesn’t seem to be the case with the AC50B. Either the inverter in the unit is extremely efficient or, more likely, Bluetti has taken the inverter overhead into account when specifying the actual capacity of the AC50B. Something I hope other manufacturers start doing.
OVERALL USER EXPERIENCE
At the end of the day, these outright run-time numbers, while important, are not what defines any product. It has to be usable in a variety of circumstances and this is where the real value of the Bluetti AC50B is evident.
The unit is small enough to store just about anywhere that is convenient and its light weight means it is a true grab-and-go appliance that you will find uses for every day.
To give you an example, we were looking after a friend’s property and I needed to do some hedge trimming. All I had available was a mains-powered hedge trimmer and there was no power available along the driveway.
No problem. I just grabbed the AC50B, an extension cord and the trimmer, and I did the whole driveway in a little under an hour. This may seem mundane but consider the trimmer was rated at 500W. Without the Bluetti, I would have needed to drag a heavy petrol generator down there to do the job. That would have been inconvenient, to say the least, given the distance between the shed and the driveway was about 150m! The lightweight and portability of the AC50B made the task so much easier.
FINAL ASSESSMENT
Just like my old WRX, the Bluetti AC50B shows that when a manufacturer focuses on performance, simplicity and the overall user experience, forgoing some of the unnecessary bells and whistles, a great product is the result.
Yes, there is room to improve the Bluetti AC50B, as is the case with any product. I would have liked at least one more 240V outlet and perhaps a slightly higher solar input limit, but these are minor quibbles.
Bluetti has hit a real sweet spot with the AC50B in terms of its performance and usability. They’ve also put a realistic price tag on it with a recommended retail price of just $599. Combined with Bluetti’s generous five-year warranty, that is excellent value for money.
