The Electric Gardener – Part One

“Get that evil oily smelly loud machine out of my garden!”  This was what I got from a dear gardener friend as I pointed my 1967 Gravely tractor with the “Power Plow” attachment – a tool that can only be described as a food processor for soil – towards the task of turning her vegetable garden one spring.  Here I thought I was being such a nice guy.

She was a soil-studies major at the University of Maine, and lord help you if you called it “dirt”.  Her contention that the grease, oil and airborne pollutants coming out of my venerable old tractor were bad for her plants is far from unfounded.  Small engines have virtually no anti-pollution and emission controls required.  As a result, “A 2001 study showed that some mowers emit the same amount of pollution (emissions other than carbon dioxide) in one hour as driving a 1992 model car for 650 miles (1,050 km).[10] Another estimate puts the amount of pollution from a lawn mower at four times the amount from a car, per hour” (From Wikipedia) Not to mention the noise.

The mower above was found on CraigsList for free- a little electric mower that wore out its batteries.  I picked it up and tossed some of my old scooter batteries in, and voila- I’d saved the thing from the landfill, used my old scooter batteries for something worthwhile, and got myself a cordless electric lawnmower.  This got me to thinking.  I know, a dangerous thing.

How much of a normal compliment of yard and garden equipment could be electric, or could be converted to electric?  I’ve been using a corded electric lawnmover and weedwacker for years.  From the perspective of noise alone, it’s wonderful.  An electric lawnmower simply makes a whirring sound, and depending on how near your neighbors live, you can run it in the early hours of a weekend morning with no fear of waking the entire neighborhood.  For a small lawn or garden, and with a little practice and observance of the prime rule of electric corded lawnmowing (always turn the handle towards the cord source, never away), it’s a perfect solution.  You don’t get how much the smog coming out of a mower effects you, personally, until you use an electric- and you notice you can breathe, your ears don’t ring and your clothes don’t stink.

But what else is out there?  A simple search for “electric garden tools” gives you a staggering array of stuff- from the lawnmowers and weedwackers right on up to electric chippers and log splitters. Chainsaws, rototillers, the list goes on. Many of the tools are for a small urban or suburban lawn or garden, but some of them are pretty robust. Most of the big ones are corded, so you’re limited to using them within 100 feet or so of your outlet. This is where it gets interesting, though.

You can, running an AC to DC inverter, use big 12 volt batteries to power normal household power devices.  They use them on boats, for example- you use the 12V boat power to run an inverter, and you can plug your toaster in while at sea.  You can do the same thing with any application that you can bring batteries to.  This opens up a whole world of conversion possibilities.  Let’s go through them.

Starting with simple corded equipment, if you have, say, a log splitter that you never operate too far from the woodshed, you can, pretty easily, pull that big old gas motor out and replace it with a sufficiently powerful AC, household current electric motor.  Most every motor has a standard output shaft configuration, and you just need to couple it to the hydraulic pump.  On a chipper you’re not running hydraulics, it’s a simple belt or chain drive, or even direct drive.  The big deal you have to worry about is having enough power- in electric motors that translates to physical size- and matching the RPM of the original equipment.  If you have doubts, you may need to do some research on electric motor specifications- it can be a little confusing understanding power ratings for the non-engineer.

For units that are made for AV household power, if you have enough battery power and a big enough inverter you could, for example, put a stack of old lead-acid batteries out in a shed in the back 40, and plug in there- miles away from “the grid”.  I’ve found that most auto salvage yards sell lead car batteries really cheap, too- when a car wrecks, most often the batteries still have a lot of life in them.  Once again, there’s the salvage/recycle angle.  Here’s where it gets interesting.  How do you charge up that little shed?  

Solar battery charging kits are getting remarkably affordable.  So are wind turbines.  And, the stuff can be bought at places like Northern Tool.

In a lot of cases, these units come complete with at 12V charging system, since they’re designed for marine or RV use.  You don’t need a lot of charging power either, depending on how you work, since the charging shed could be sitting for a few days between use.  Mowing the grass, for example, needs a station that can recharge the batteries in about a week, since it takes that long for the grass to grow back.  Even if you’re using battery, or cordless machines, you can use this kind of “off-grid” power.  A simple solar or wind turbine that is wired to provide 12V charging can go to an inverter, that then you plug your lawnmower charger into.  If the solar system you get is wired to produce household AC, then it’s even easier- just plug the charger directly into the solar system.

How cheap are we talking?  You can pick up a solar array for under $500.  The turbines go for about the same money.  There is certainly a payback on this for not using gas, and not using the “grid”, but that’s not even really the point.  The real reason this is such a great thing is the quiet, clean tools in your little corner of Eden.

Putting all this together may be a challenge, or at best a learning experience, but it shouldn’t be intimidating.   Running a battery-powered tool is as simple as pie- simpler than even a gas tool, since it doesn’t need any periodic maintenance.  Running a corded tool is even easier.  Converting a gas tool to electric is a good winter project for the home mechanic, probably something you don’t want to take on if you don’t know the business end of a crescent wrench, but setting up a solar or wind generating station is not as tough as it may seem.  The big challenge is tapping into the grid.  We’re not doing that- we’re running a self-sufficient charging station on the wind and the sun.

This does all take some getting used to.  Hearing the birds singing while you’re mowing the grass, well, to coin a phrase, is priceless!

Want to read more about electric gardening?  Check out all the posts:  The Electric Gardener: Part One,  The Electric Gardener: Converting the Tiller, and The Electric Gardener: The Solar Charge, and The Electric Gardener- Sunday Morning Chain Saws.