MHPowows 40W Solar Panel Review

Let’s say you are going on a multi-day adventure that may require you to have more power than what can be provided by portable battery banks? Or you simply don’t know how much power you’ll need but it’s important that you don’t run short.

For instance

Maybe you are a hunter and may be out for a week in a very remote place. Ensuring you have your GPS and emergency communications always powered up is crucial.
Or maybe you are setting up a base-camp from where you will do day hikes for multiple days or maybe you’re on a multi-day photo or video shoot. Your navigation, emergency devices, smart watch, camera gear, and flashlight are all important to keep charged.
Or maybe you are camping in a place for a number of days that does not provide plug-ins for your power needs. Having a nice power safety net helps you enjoy that trip even more.

In all these cases, everyone in your group could carry an excess number of charged battery banks and hope no one runs out of power. Or what if one person in the group carries a solar charging station that does not weigh more than all those batteries and gives you essentially limitless power?

MHPowos recently asked me to review their 40W solar panel. This 40W system is a larger and heavier panel than I would normally carry on a backpacking trip. But in circumstances like I mentioned above, where the carry is not too far and I have critical power needs, this may be a reasonable and cost effective option.

So, let’s look at this solar panel.

Physical Inspection

It’s a foldable panel that can fit into a backpack. It folds down to 12.5 x 8.8 inches and it’s 1.5 inches thick.

Doing a quick study of the construction: It’s made from sturdy scratch-resistant material – it has solid construction and stitching on the seams, strong velcro to keep it folded in transport, it has a reinforced zipper on the pouch to protect the output port panel from rain and dirt, and there’s an ample pouch to store chords, a phone, power banks, and other devices while they are charging.

What does it weight? Without the cables it weighs just a little over 3lbs (1.36 kg) – which is about the same weight as 2 or 3, larger hand-held battery banks.

It has sturdy grommet holes in the corners and it comes with two carabiners so you can hang it or attach it to a tree or anything convenient. I’m sure using parachord would be a good option too.

It also comes with a USB-C to C cord, an I-phone adapter, and a 7 in 1 solar cable that is compatible with almost every power bank on the market.

Waterproof Rating

It has an IP65 Waterproof protection rating. For those familiar with this rating, it’s a standard rating system for mechanical and electrical devices to test for solid particle and liquid ingress protection. See this link to study up on this standard.

Essentially, an IP65 means it’s been tested to show that it is dust-tight and that it can withstand being in the rain for a few minutes.

Power Specs and Proper Operation

There’s all kinds of electrical specs on this, most of it will only mean something to the electrical engineer - so let’s bypass most of that and break down what is most important for you:

Power Output. Power output is all about how much power this unit is capable of delivering; which translates to how fast it will charge your devices. Power is measured in watts (W).
- This has a 40W maximum power output. (If you aren’t familiar with the formula: wattage is the product of voltage and current. Voltage X Current [measured in amps] = Watts.)
  - The max voltage is 19v and the max current is 2A (38W). It doesn’t calculate to be 40W because some power is absorbed by the internal electronics.
  - BUT... because it’s a 40W system doesn’t mean that you will have 40W of power charging your device. It depends on how much current (amps) your device demands and keep in mind each output has current limitations by design. I’ll break down those two factors:
    - #1 - I plugged in my Samsung Galaxy 21S into the USB-C output – and I measured the voltage and current going to the phone with a simple multimeter (the phone had “super fast” charge enabled) – it read 5v at 1amp. Doing the math, that’s 5W of power, not 40.
    - #2 - This unit has three output ports – a USB, USB-C, and a DC output (5A max). The USB-C output, for instance, for a 5V device (like most phones) can supply up to 3 amps - 5x3 = 15W. Once again, not 40. But if your phone is designed to draw only 1 amp, as in my phone, you get 5W’s max. By the way, the USB and USB-C ports can output 5, 9, or 12 volts – and that is automatically determined by the circuitry – it will automatically supply the appropriate voltage for your device. The DC port is 7 to 28 volts at 5A max.
  - All this math is fine, but the big take-away here is that the power output is going to change depending on what you plug into the unit and it will very likely be smaller, maybe much smaller, than the max rating of the panel.
- Please note that I’m not trying to discredit this unit – all solar panels on the market will communicate there max power capabilities the same way. It’s not deceptive, they are technically correct. But you should understand how this works.
- Also, there are two other major factors that impact output power:
  - #1. For max power out you must have max sun intensity. Even just a little bit of sun blockage from clouds or shade on any of the panels will reduce the output power.
  - #2. The alignment of the panels to the sun must be at 90 degrees to get an optimal output. So, if you are carrying this solar panel draped off the back of your pack, most of the panels will be facing behind you and parallel to the ground - the panels won’t be at 90 degrees to the sun unless it’s a rising or setting sun directly behind you. Also consider that you may be hiking through shaded areas or at times be facing away from the sun. So the direction you are hiking in relation to the sun will make a difference.
However, even with less than full sunlight on these panels, they will output power. But it won’t be optimal unless these two conditions are met. There are instructions on the panel that show you how to set it up. It’s an easy set up, but it’s very important to do this properly.
The Red Light. There’s a red light on the output ports module. When the panel is set up properly and the sun intensity is enough for it to produce power, the red indicator light will come one. If it is off there is not enough sunlight for it to produce any power. This light is NOT an indicator that your devices are charging. To verify your devices are charging, you’ll want to refer to your device, which should have it’s own charging indicator.
Three Output Ports. This panel has three output ports. All three can be used at the same time, as long as the sun intensity is strong enough. This is why setup is so important.
Fast Charging. The solar panel has a built-in safety protection system that regulates the current for fast charging. For instance, my phone has fast charging capability. And so it will accommodate that. Fast charging is only possible when one port is being used. If you have one device connected and it is fast charging, and then if you connect a second device, it will switch to normal charging mode. This helps prevent overheating, because the higher the current, the higher the generated heat on the electrical components. So, this is a great safety feature.
ETFE Cell Type. I want to call your attention to the fact that these panels are ETFE panels. This is the type of material used when manufacturing the panel. This material:
- Makes the panel easy to maintain (wipe off with a wet cloth); they perform well (although diminished) in low light conditions
- Is flexible
- Is light weight
- Can tolerate high temps
- Has good efficiency with a 23.5% max conversion – which is hard to get a conversion rate better than that for portable panels.
- So, when you see “ETFE” it means they are using the best type of panel for something portable like this.
Warranty. It comes with an 18 month warranty.That’s pretty good for portable panels.

Testing and Review

I used this solar panel to charge a number of my devices separately: my 60000 mAh power station, my phone, my 10000 and 20000 mAh power banks, my GPS unit, my smart watch, and my flashlight.

I didn’t do any specific tests on how long it took for each one to charge, because the charge cycles on each of these units is a little different (non-liner) due to the type of charging circuitry in each of them, and that was a little bit more math than I wanted to do here.

But I can say that the charge time was much faster than my 10W solar panel – as you might expect. By example: My 60000 mAh power bank charged from half to full in just a few hours in full sunlight.

So, everything here performed as expected. All output ports worked as designed.

Then I tried charging multiple devices at once. I had my phone, my 10K mAh battery bank, and my 60K mAh power station all plugged in at the same time. The light stayed red and all of them were charging at the same time. So, that’s something you could do.

However, by design, when charging multiple devices at the same time, you should expect much longer charging times because everything that is plugged in is sharing all the available power. When possible, my personal recommendation is to charge only one device at at time. I find this to be the most efficient use of any portable solar panel. But, certainly you can opt to charge multiple devices at the same time if you like.

Results / Conclusion

I’ve tested and used a lot of these type of portable solar panels over the years – some of them were not great: they don’t have a high conversion rate, much lower than expected power output, durability wasn’t great, poor construction, low quality materials, etc. Well - this one is NOT one of those. This unit worked great in all respects and as advertised and expected.

It’s not something I would take on a long hike, just because of the weight. But I would take it on a shorter hike into a base camp kind of situation where there’s a reasonable chance that I will need a good amount of power and where it wouldn’t make sense to carry a bunch of charged power banks.

I will also used this at home to keep my portable power banks charged for emergencies and to help offset my day-to-day power use: charging my phones, watches, and other rechargeable devices. For instance, I have a bank of rechargable batteries that I use for various things around my house. I keep that plugged into my 60K mAh power bank, which I charge with this solar panel. So, there are many common day-to-day uses for this panel.

This is one small investment that will reach ROI is a short about of time, then, after that, it’s free power for as long as the panel still works – which could be years – the sun is my money maker. This is no-brainer stuff for me.

I have only one suggested improvement: it doesn’t have a built-in stand. I found that if I wanted a good angle for every panel, it got a little clunky to set up – I got one end set up and the other end moved. I was going back and forth a few times, bracing it on whatever was available to get the right angle. But, honestly the size of the unit is right on the line between needing a stand and maybe not needing a stand. So this is not a big deal, but something worth a brief mention.

Discount!

Follow this link and enter the discount code “DavidA10” to get 10% off your order. Note that MHPowos does not sponsor this website, but they have provided me with an affiliate account to help me offset the cost of maintaining this website. Thank you for your support!