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How to use solar panels to power a motor? Answered

 I have a motor that is rated at 6V. I also have two solar panels, which both "work."  However, i am unable to simply connect the panel to the motor, and either their is something i do not know about solar cells, or that i am simply wiring it wrong.  I need the motor to pull a fairly light weight, so the problem is more getting the thing running. Any help will be appreciated. Thanks!


how can i use 250v capacitor run motor to run on solar panels which is 37.6 dc volts 250watt

HI.I want to use solar panel to run my 220V, 250W AC motor. is it possible?

I have a 100mA solar panel that was used to charge a battery and then to inverter for back up. I do not need the back up anymore. I am looking for a way to make use of the solar panel without battery; can I use the panel to power a motor to lift water from ground floor to the rooftop?

I have a small six volt solenoid mounted on a wheelchair I need it to open for 30 seconds and close 2 to 3 times daily. Can I use a power solar panel to power this unit? Or two 3.8v cell phone batteries linked together?

can anybody help?

i need suggestion for 3volt dc motor that runs from the power of a solar panel

Forget it, doing it your way, you will need the strongest sunlight to get enough current. And will that sun light be there when you need it?

You dont say what wattage or voltage your solar panels provide, nor do you state what kind of motor, and what you yourself consider to be a light load.

And did you know, that any motor wanting to start up, needs a lot of current to begin spinning? I have checked a cordless drill motor starting up with NO load, except for its reduction gearbox, it pulls a number of amps from the battery, a second later when its spinning, its down to a fraction of a amp.

And your motor will be starting up under light load, consider a centrifugal clutch to cut in the light load once the motor is up to speed, however I dont that will fix your problem, but will help with my work around below.

Have you tried starting the motor by spinning it yourself, and seeing if solar will continue running it?

I suspect you might have a 12-volt panel meant for keeping a storage battery on a boat or in a car charged up, when the car or boat engine is not used for some time. Two of those wont do much.

There is also something like back EMF from motors which I dont have the words to explain or fully understand how it could but which could harm your solar panels.

I have a number of 25 watt panels, I dont believe the cost of such a panel is worth any project that only runs a motor under light load when the sun is just right..

So use a storage battery like most people and make FU LL use of ALL your panels output. Run some LED lights off the battery, when you need some light for example.

I have been told that some panels wont put out power, unless the load on them is correct, so, if yours contain any electronics to protect from the panels discharging the storage battery when the sun is down, they might also be seeing the stopped motor as a short circuit, so to safeguard the solar panel. it cuts out, rather than try starting the motor.

I suspect you might want to run a fan when the sun is hot?

AC motors use big capacitors to store some power, to reduce the load on the powr supply, for when the motor starts up. However, you are using a DC motor, and in any case, a capacitor discharge/surge could damage your solar cells.

So a work around if its a fan.

Run the motor off a storage battery, the motor can be switched on by a miniature relay, trigered by power coming from the solar panel.

Doing it that way, gives you a chance to decide how much sun before the relay triggers.

I wonder about broken cloud coming over, the motor would be stopping and starting, minute by minute, thats not good for the motor.

Go find one of those cheap battery changers, that plug into a car's 12 volt cigarette lighter, and which charge 4 pen light type batteries, in NZ we call them AA and AAA (Triple A) That would be 4.8 volts though, however, your motor will be under light load you say. Or 6 AAA giving 7.2, your motor can cope with an extra 1.2 volts.

But its not wise to charge while the motor starts up and runs

Solar panel into that charger, when the motor needs to start, the solar panel cuts out charging, so the motor can  take current from the AAA, once the motor is up to speed, the AAAs cut out, the solar panel powers the motor.

When there is not enough sun light to continue running the motor the motor spins down, which switch's the solar panel back to topping up the AAAs until there is enough sun again, to restart the motor.

I dont know how long the AAAs will survive like that, because that kind of brutal use could destroy them pretty soon. Buy those really cheap AAA meant for solar garden lights maybe.

If you are not good at electronics, use miniature relays for all the switching, and buy a cheap kit-set like what is called a magic eye to detect light, a miniature relay and a 9-volt battery. (maybe instead of the 9 volt battery, run that off the solar panel (two voltage reducing diodes) as you really onluy need the detector when the solar panels are generating.

I am sure Lemonie can help you with details, and think of a way to use the solar panel to replace the magic eye kit-set.

If that does not work, go buy a proper storage battery, and run your motor the traditional way, and use the solar panel the way its supposed to be used, which is to charge a battery.

Are you aware of economics? A lot of time your investment  in solar panels will be wasted, sitting around doing nothing yet receive plenty of sunlight to slowly charge a battery,while not enough to directly run the motor.

So rather than charge a battery maybe 8-hours a day, it just runs the motor when the solar panel is pointing right at the sun, maybe 2 hours maximum per fine day? My panels even charge batteries on a overcast day (I monitor voltage output, when the voltage is above battery voltage, its charging, however slight, its still a gain.

Signed, Peter the very detailed Aspie!

Good luck

Can u help? Long story short I want to make a vertical awning for my parents deck pretty simple plan a 4in pvc pipe wrapped in a boat cover like material, the ends of the 4in pipe I'm going to drop down to some were around a 1in shaft OC sitting in 2 bearing blocks (one at each end obviously) I would like to use solar power on a dc motor with a DP switch but I want to keep it small as it will have to go on top of my parents pergola.... would it be better economy wise to go bigger and also use the battery for some LEDs?

Wow peter...Thank you for taking the time to explain this.
I, too, am looking for a way to power a small DC motor with a solar panel.
I found the following link, which mat be helpful

Been SO many years since I used this part of my brain, having a hard time kick starting it! HA!


hie daniel

Can give me an explanation...whether i can run a 1500watt motor directly by solar panels.if so how much size and power of solar panel should be..actually i am participating in a competition of solar car where i need to run it without batteries.

Ok, It can be done. What are you missing? It takes a lot of energy to start a motor running. Get in a car and put the foot down and it sucks up fuel fast, when you are cruising its economical, does not use much fuel. Electric motors are the same, start up uses up to to 8 times that for which the motor is rated at (running current in this case). So they don't tell you that huh? This is the reason your motor is not working, providing your solar panels can supply the rated motor current and voltage. So how do you get around this. Use either a capacitor or a small battery in the circuit to get the motor started, then the solar panels keep the motor going. The solar panels charge the battery when the motor is not running. Obviously with this setup you are not going to run the motor 24/7. Solar energy is not 24/7, doh. You will need a solar charger for the battery, a small battery and the motor. This is just a start and its what these guys have left out. Now there are things to consider: solar panels must meet the running voltage and current of the motor at all times the motor is running other wise the battery is being drained. Run the battery completely flat too many times and you will have a dead battery, the battery has to be rechargeable, a capacitor will work regardless if it loses all its energy or not. Your battery or capacitor has to have enough energy to start the motor. The motor will start in a second or two, they are pretty quick. If you don't get the battery up and going the motor can burn out. Solar Water pumps are designed with all this in mind. Look them up and do your research. There are a lot of simple calculations involved and a circuit if you want to safe guard the battery and motor. It can be done.

I want this motor worked in this soler penal so tell me any suggestion or solution

shaft type 1.jpg

Please send the information on 2 KW DC motor of 48v ,60v work with solar power and also necessary instructions if any

you can try with a different motor. this store here says they have motors that run on solar cells

i would try with a motor savaged from a old cd or hard disk drive...

In general small panels (individual solar cells) provide less than a volt, and multiple cells in series + to - will provide more voltage.  If the panels combined do not produce 6 volts its not gonna work.

You're probably not getting enough power out of the cells, simple as that.


Also, Unless you have a DC motor you will need an inverter to convert the DC to AC. You will need at least 12 Volts of output from the panel to power an inverter, unless there are some that can work with less input voltage,but I am unaware of them.

Amperage is very important to run motors. If the Amps (or flow) of the electricity is not enough, than the motor will not turn (and just suck up the electricity). The amperage produces by solar cells is proportional to its size. Larger the cell = more amps.

I don't know the size of your motor, so you should look online and try to find the amperage/current requirements.

A 2'' x 1'' cell will produce .5 volts and .4 amps.

Some more info about you cells and motor would be great! What's you project for?