Solar Lawn Mower




Introduction: Solar Lawn Mower

this Instructable will show you how to mow you're grass using solar power to charge the mowers batteries

Step 1: What You'll Need

-battery operated lawn mower
-12 volt solar cell
-wire (red and black)
-multi meter
-multi tool (I used my leatherman)

Step 2: Wiring

you'll need to cut off the cigarette lighter plug in and then strip your wires .you will also need to cut two lengths of red wire and two of the black and strip both ends of those .when using stranded wire its best if you pull the insulation away slowly as you twist it to keep the wires neat

Step 3: Connecting the Wires

locate the positive and negative terminals on each battery and connect the wires accordingly .it uses two 12v batteries connected in series circuit and you have to undo that connection .and wire it in parallel circuit to charge .then you must undo that and reconnect it to mow

Step 4: Bring Out the Solar Cell

now that you have those connected you will need to connect the red wires together and connect the black wires together

be sure you disconect the the jumper wire so theres no short and the solar cell is able to charge the batteries

once thats done you'll need to connect the solar cell to leads

Step 5: Charging

once you've hooked it all up all you need to do now is set it in the sun and let it do its thing .it doesn't have to be a cloudless day for your solar cells to work but they do work best in direct sun .it takes about 4-6 hours to charge depending on how clear the day is and position of the sun in reference to the solar cell .and it is about to cut thick grass for 20-30 minutes on the mulch setting so that time would be greater if you were collecting it in a bag

the solar cell does not stay connected for use of the mower (it is only for charging) .and the batteries have to be hooked back up to the manufacturer's specs .but for free power the 3 minutes it takes to do that is worth it

.it only took me about 45 minutes to complete this project since I had all of the stuff just laying around (my father is a "junk" collector)

I'm sure you will be able to locate a battery lawn mower online .my dad bought this one on clearance for somewhere around 75 dollars ,and you can purchase a 12 volt solar cell for around 65 dollars from harbor freight

I hope this is helpful and I would like any feedback and criticism you would like to offer as this my first instructable

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    118 Discussions

    And my only question is, do you still have to push it? Just kidding. Great job.

    such a cool mower, you made it awesome. amazing huh.


    2 years ago

    It needs a solar charge controller.

    Uncontrolled charging ( hooking the solar panel straight to the batteries) can heat the batteries up and could set them on fire or even could make them explode. Besides, uncontrolled charging will reduce battery life a lot.

    1 reply

    you know a lot for a baby

    I think most the comments were very constructive regarding this instructable. We need more of such maturity on this website. I was once told, "Those who do not fail are not trying hard enough". This by no means is a failure, I think it is great. It is great when someone has the courage to make an Instructable and others are helpful with suggestions and it continues to be "tuned". I will throw my two cents in as a trained horticulturist. As far as mowing, the average homeowner mows once a week, perhaps twice during peak growth, dependent on irrigation and season. (Allow the ignorant to dream) What if this idea could be combined with some others such as low power/high torque motors for propelling the mower? Removal of the solar panel(s) making a charging station. Combine that with the tech used in such as the "robot vacuums" or "invisible fence". I dream more, when the electric power reaches a near depleted level the "mowing unit" if you will, returns to the charging station until recharged yet only mows during a set time period. Finally, what if the charging station had a rain sensor as well as the mower. If it is raining it does not mow during the set times or if it starts it goes back to the station. IF these techs could be combined in one unit you would have a "robotic mower". I do not have the skill nor tech knowledge. I am just casting out an idea. Please be kind in your comments.

    7 replies

    I'm dreaming of this too. I hate mowing my lawn!!

    I've been tinkering for a while with the Arduino microcontrollers which will serve nicely as a 'brain'. I've also just started out with stepper motors coupled via an EasyDriver stepper driver, which as the name suggests, is VERY easy to hook up.

    It'll likely be less of a mower, more of a 'grazer' I think. ;)

    Beardy, Exactly, "Grazer" is the concept I was trying to explain. A solar powered robotic mwer that does not mow the whole lawn at once but continually grazes maitaining the grass continuously. The effect would be the grass never grow over the set mowing height, never giving that "needs to be mowed" look. I wish you luck and would love to hear about your progress.

    hey cobaltxxxfusion! It's been a while and the desire to build a lawn grazer hasn't gone away. Happily, I recently started teach electronics to a couple of teen boys at a local private school. They've really grabbed hold of my suggestion to build a robo-mower ;) so we're on our way. There's nothing to show for it yet - we're still exploring the design considerations - but I'll post something somewhere as we go. kr

    yeah I think they do have them I seen it on a segment on a discovery science show can't remember the shows name but the segment was called tech toys it uses a magnetic wire to know where not to mo and has an alarm if someone tries to steal it its pretty cool Aaron

    Great Instructable!!!! I do have a few questions, hopfully it is not in the comments below but; how long does the battery supposing it is fully charged support mowing? How long can a fully charged battery by any means cut what square meter or square foot of grass, how high, and how long? My family has many acres, my parents have about 4 acres(my father cuts). It would be interesting to mount more batteries on this unit, how many can it support? I wonder how much for a riding mower, and how much energy it would require? since the mower is moving at low speed I suppose weight does not have much of an effect. what horsepower is the lawn mower you are using? Again great job -Inductionmind

    3 replies

    NOTE your questions do not really apply to his instructable. assume you ALREADY have an electric battery mower. Does it work for you now? this does not change that. It just changes WHAT charges the batteries. I have a battery electric mower. IT DOES have enough charge to cut my lawn. (unless its wet then it will only do about 75% of the yard :-) with that established all this does it use a solar panel to recharge instead of my wall outlet. SO determine if a battery electric mower WILL work for you IF YES then you can do this mod. if not then its not relevant since you won't be using a batteriy powered mower anyway.

    Wow... sure my questions apply, it is simple mathematics.
    Using push mower with a dc motor of (T)hp, a blade length of (U) a battery with (W) amount of joules is able to cut X meters of grass of w\ length by Y density =Y. all that has to be entered is the variables, and we can make good predictions of the area that could be mowed assuming the batteries are fully charged and the grass is as wet as the control condition, lets assume dry.

    as it is now it will cut grass a thats about 4-5 inches tall on the muclh setting for about 30 minutes .in about a 20 by 30 foot lawn (my front yard) .and as for mounting more batteries on it .I'd not do that unless you were going to go the riding mower route .as is stands now it weighs more then a regular gas powered push mower and isn't to easy to push .especially in the higher grass