Author Options:

Adding solar panel to quadcopter to extend flight time? Answered

I know I will not be able to completely rely on solar power to power the blades of my quadcopter but I would like to extend the flight time as much as possible.  I was looking at this url and started getting interested in trying to create a small panel array on the arms of my quadcopter to help replace some of the power in the battery (trickle) while using the battery for flight.  Doug Paradis had some helpful insight to the OP's question but some of it went over my head.  That's what lead me to ask my own question to make sure I'm talking about quadcopters instead.

So currently I have a light weight POS starter quadcopter that has the following battery being used...
- FB752540
- 136 Li-Po
- 500mAh 3.7v
- 4K07 1.9Wh

I have some internal space to mount small items but I would try to keep the weight down as much as possible.  I was hoping to start my own DIY project to learn more about solar power and the entire process.

I'm guessing I would need at least one solar panel (small), something to convert the power, and some type of regulator to trickle the power into the battery.  Any ideas as to how I would do this?



To being able to supply you drone from both the solar panel and the battery, you should try to use a system offering some sort of power-path management system.

The way this kind of system works is that all energy from solar panel is supplying motors and the extra needed is supplied from the battery. When the solar panel produce too much power for motors (let's say motors off), energy goes to recharging the battery. Genious!!

Suck system is embedded if that IC:

You can maybe try to buy a development board of the IC to integrate it to your project.

I made a personal project on my own using the IC. I order samples and build my own integrated circuit. The project is quite simple. The solar panel is charging a huge LiPo battery on daytime and the battery is supplying a huge LED for my plants by night using a photocell.

You should try this kind of system for your drone project.

I'm on it on my side too.

Good research and good luck on your project!

you can see the idea here


hi sir,

This is good idea, but I need to understand that how you can mannage power produce by solar panels and battery, because solar panels can't produce that much power to run all motor,so just I need to understand that how you manage both power.

Older thread but I'm confused. An array of 4 500mah batteries in the quadcopter? If that's the case, it doesn't sound like a really small quad- to me. if it can lift , 4 500 mah batts for any length of time without burning out the motors anyway. Perhaps you meant you have a Charging Array of multiple batts on the ground to swap out after each flight.

As far as the solar, I still think it's a cool idea and I might try it. What I would do on a small 3.7 volt quad is just wire 4/8 cells together to make 4 volts. I wouldn't bother trying to tie these cells into charging the battery - I would just add them in with the battery as a second power source with a blocking diode (the motors would end up drawing less on the batts). This certainly wouldn't give you any type of huge increase though and you would need to size the cells large enough to make it worth your while- perhaps small 100 mah cells. And -after some testing you could carefully remove sections of the quad body and replace these sections with small cells (would make up part of any weight gains).

Thanks everyone for all the comments! I ended up going with an array of 4 500mAh batteries instead and have more flight time. The drone I'm using is a cheap one and because of how light it was in nature controlling it with more weight on it is much harder. But in the end more batteries (in parallel) give you more mAh and that = more flight time!

I will be working on some solar projects but this will not be one of them... ;)


3 years ago

Have a 100W solar panel on the ground directly facing the sun, and have it connected to a decent charger to charge a few batteries at once, and either design your own charging topology (lithium charging is easy but requires like 0.5% precision). and as you fly, and then you can just switch out batteries one after another. Figure out what the runtime is compared to the charging time, and you can easily figure out how many batteries you need charging at the same time to sustain "continuous" flight.

Meh. forget the skeptics. it's neat academically, even if it doesn't quite balance the power equation. (you have to spend power to lift the solar panel and the solar panels aren't terribly efficient)

No, it probably won't result in longer run times. As others have suggested, adding a second battery will likely go far longer towards that goal. But it's a cool project, and you're sure to learn tons from trying it.

1) learn about creating battery charging circuits. Google it. NOW! I'd recommend finding a simple design for charging those Lipos they sell at gardening centers for installation into solar exterior home lighting units.In fact, if you buy a bargain lamp, you can gut it for the all parts necessary.

Then, at least for the first push, you can work on how to retro fit those parts into your copter and not worry about compromising the existing electronics on the copter.

2) learn about how wanting to lift a pound requires the use of power. Each ounce of weight you lift results in higher power burn, something that aeronautics engineers have been battling since the inception of the aircraft industry. That google is a bit more difficult and in general, I'd sayu, crack open your physics books.


3 years ago

There is a LOT of science and engineering that goes behind making informed choices on the best solar panels to use, and I do not know even the surface of it. We need to take into account where you live, the average solar radiation that you get in your area on a sunny day, and then take into account the percentage of usable solar energy by the different solar cell technologies and their efficiency, trigonometry is used when the angle of the solar panel is not directly facing the sun, and the effective area of the panel when receiving the indirect sunlight, etc, etc, etc!


3 years ago

Ehh, a decent sized quadcopter, at hover, may draw 4A@11.1V per motor, and 0.5A@11.1V (w/ linear regulators) so with 4 motors, thats 16.5A, @ 11.1V = 183W of power. Thats with no additional weight. I have not measured my quadcopters performance, and the 4A/motor figure is an assumption of a perfect hover that a friend told me.

To get a solar panel that delivers that much power to a mid-sized quad, it would be too heavy for the quad to lift. Even if it could given enough power and full throttle, the current draw would become MUCH higher, and the power the solar panel delivers is not enough to compensate. Even with the additional power, my guess is that the the flight time will be REDUCED.

Solar power technology is still, to consumers, 10-20% efficient, and the power rating that you see is in the best possible conditions, with direct solar radiation, with the correct amount of impedance matching and loading of the panel. Even still, the power-to-weight ratio of solar cells is not good, and especially not the surface area-to-power ratio. In other words, you need LOTs of surface area to get the power you want. ALl that surface area will make the quad unstable, as the wind can catch it like a big sail, and blow it away like a leaf falling from a tree.

I think the closest solution to making this work would be the thin-film flexible panels. They, by design, are lightweight, as they are made onto a plastic substrate. They are also relatively cheap, but the suffer from being very inefficient. I think they are less than 8% efficient or something. Even if they are light enough, and deliver enough power, then you need to worry about how they will be set up. They cannot be directly below or above the props, as the props need to blow air in an unobstructed path to be the most efficent possible.


3 years ago

For the same weight, a bigger battery will give better results.


I'd go for a Secondary battery, that can be swapped out for fast turn around time.

be sure to mount it directly underneath the C.O.G. or your Quad-Copter my look like it has a Drunk Pilot >.>

I'm curious, with a 500ma battery, how long is your flight time? and how large is the assembled kit? maybe a link? >.>

That was my thought too. You will get more power from a good battery than you will from a solar panel, assuming the weights were equal. Solar can give you power over a length of time but not a lot of immediate power.

I read they were developing a new type that could take advantage of all the color ranges and thus produce more power. But it is a ways off still.

Well, there is some amount of power, P1, in watts, required to keep your quadcopter in the air. Moreover there is some amount power, P2, in watts, which could be produced by a weightless solar panel array, in full sun, attached to this same quadcopter.

Now consider the ratio, a = P2/P1. If a is small, for a less than about 0.2, your run battery time could be improved by a factor of approximately (1+a).

I mean this is using the approximation 1/(1-a) ~= (1+a), which is good for small a.

Anyway, you know, try to get an estimate for that ratio, because that ratio is kind of what tells you if this is a good idea or not.