Corded or Cordless, Which is More Green

We get a lot of woodworking-related questions from readers. Most deal with articles published in recent issues of Popular Woodworking and Woodworking Magazine. But often, we’ll be asked about projects from old issues , some from as far back as the early 1990s. And sometimes, we’ll receive ideas for future articles and other worthy matters.

This past month I received a question about power tools, specifically drills. It seems that new drills, whether it’s a drill driver, impact driver, compact driver or some other type of driver, are constantly being improved upon and released by manufacturers. The latest drill improvement is in battery power, moving from Nickel-cadmium and Nickel-Metal hydride to Lithium-ion power packs. Many drills feature 18-volt Lithium-ion batteries, but it’s not uncommon to see 24v or 36v batteries stoking hand tools.

With all the focus in today’s world on being “green,” one reader wondered if a battery-powered drill or an old-fashioned corded drill was better for our planet , which power source uses less energy. Put another way, it takes a certain amount of energy to charge a battery. That battery can, for the sake of discussion, drive 100 screws. If you then drove 100 identical screws using a corded drill, would you use more or less energy than it took to charge the battery?  

Interesting question , and something I couldn’t answer, but I knew where to turn. I contacted Bryan Wright of Strata-G Communications (the company represents Bosch Power Tools.) He sent the question to Edwin Bender at Bosch , he’s the group product manager for cordless tools.

Bender says that every application or operation requires a certain amount of power, measured in watts. And if you could hold all other variables constant, corded and cordless drills use roughly the same power.

According to Bender, “If you dig deeper and want to split hairs, a corded tool should typically be a little more efficient and therefore use less energy because it works off a higher voltage (120v or 220v) than cordless (12v-36v).” He goes on to say, “If you hold the power constant (for one application) then a lower voltage means you draw more current.”

Bottom line: It’s nearly impossible to hold the variables constant and any variations would be so small that a simple answer is that both cordless and corded tools consume almost the same amount power. So using Lithium-ion power sources does not hurt the earth any more than a corded tool , just dispose of any old batteries properly. That doesn’t mean in a landfill.

Now, here’s my question for you. Do you prefer to use cordless or corded tools? Do you find situations where it’s best to use both? Leave a comment to let us know.

, Glen D. Huey

21 thoughts on “Corded or Cordless, Which is More Green

  1. Alan

    As a Master Auto Mechanic and a beginner woodworker, I use power tools and hand tools every day under extreme conditions.
    For all of the work I do I have found that as long as I have enough power to complete the task (sometimes only pneumatic tools work on cars), it is ALWAYS BETTER to have no cord or air line attached to any power tool. This also speaks to my preference for hand tools for both my work and woodworking.
    I read somewhere recently: "anything with a cord eventually ends up in the trash…" So– go small & nimble, powerful and CORDLESS whether you can go without power or not.
    Don’t forget to shop around… the power in cordless tools IS out there. I even have a cordless impact that will do lug nuts…

  2. Chris

    Having to deal with cords that are always too short and extension cords that are always too long is the price I am more than willing to pay for full-powered tools that always get the job done pronto without fail once everything gets plugged in. And after watching a ‘friend’ use his cordless drill, running down in mid-job, not having a charged spare, too-low torquw for some jobs, etc. I swore I would never make my own life more difficult by getting anything cordless.

    Having said that, around a decade ago I picked up a couple of 7.2v Skill driver/drills on closeout at Wal-Mart, and used them for the light duty work they were born to. Of course they are underpowered, run out quickly, fade out durig storage, always need a battery change in mid-job, etc. but for those quick little jobs they have been great. Cheap, lightweight, handier & faster than a manual screwdriver. But often frustrating.

    Recently, a fellow contractor I worked with had me try out his 28v L-I Milwaukee hammer/driver/drill and also the circular saw in his multi-tool set. Rather heavy but very interesting. After some research I learned that the new 18v L-I actually draw the same amps and produce the same power, only the 28v lasts twice as long per charge, and weighed a lot less and balanced better. For the sort of intermittent use we put them through, one charged 28v battery would get us through a couple days’ work so the 18v L-I set with extra battery would suit me fine and I bought it.

    Then he mentioned that he’d had to replace his 18v (NiCad) Milwaukee drill because the brushes wore out and were not serviced separately like all Milwaukee tools used to be; the entire motor frame had to be replaced; parts & labor total cost only pocket change from the price of a new one with extra battery & charger, so he bought a whole new complete package. (After that he upgraded to 28v. — unimportant sidebar story.) This rang alarm bells in my head, so I checked my shiny newL-I 18v and lo and behold, MADE IN CHINA! Likewise the rest of my set except one that gave no country at all. Now the last thing I want or need is throwaway tools made in China, so the whole kit went back, and now that Milwaukee is now owned by a Chinese company I am done with Milwaukee altogether.

    But I did get bit by the Cordless Bug when it comes to drilling and driving screws etc. Upon more research, and a factory rep’s assistance, I finally got DeWalt’s (at-that-time promotional) set of 18v NiCad driver/drill, driver only, two batteries and single charger all for about $300, two tools with batteries for the price of one plus not even the second battery, and I am absolutely delighted with them. I frankly do not expect to get any other cordless tools, however, mostly because I changed careers, away from contracting due to bad state law.

  3. Jerry M. Johnson

    I do not een own a cordless drill. My wife has a couple but whenever I tried to use hers, the battery has either been no good (cannot be charged) or it needs charging. Using a corded drill is no problem.

  4. Mattias in Durham, NC

    The corded drill is clearly more environmentally friendly. Not a big difference in energy consumption, though. Even with proper disposal of batteries, that’s where the big environmental cost comes in – energy used and pollution caused when making/disposing of batteries.

    However, I don’t get this article. Why does it matter if we use corded or cordless to be "friendlier to the environment" when it’s a tiny, tiny, tiny fraction of the pollution caused by 1) cars/other transportation, 2) heating/cooling of houses/other, and 3) my freakin’ table saw during 10 seconds’ of use. I like my cordless drill, and I’m keeping it.

  5. Keith Mealy

    It has been a long time since I was in physics class, but I don’t see how a rechargeable could be more efficient than a corded. No step along the way is 100% efficient, and it’s not possible to be more than 100% efficient (you can’t create more energy than you put in. Such is the dream of perpetual motion machines.)

    Or I as learned the laws of thermodynamics:
    1. You can’t win
    2. You can’t break even
    3. You can’t leave the game

    In addition there is the disposal problem not only of dead batteries, but of tools with dead batteries because it’s cheaper to buy a new kit with two batteries than two batteries.

  6. John D. Williams, Jr.

    Obviously corded tools are greener. There’s a drill and a screwgun from my sheetrock days plugged in and ready to go down in my basement, with more than enough speed and power for any job I throw at them. But during the week I’m a Habitat volunteer, and there the cordless driver/drill and 5 1/2" saw are used as much as my 6 1/2" worm drive, motorized mitersaw, and 1/2" Milwaukee drill. It’s all a matter of which will do the best job in the location I’m at, and with the materials I’m using. Also whether or not we’ve installed the temporary electric or not yet. Yes temp elect is far more green, as well as quieter than generators. And when the High School or College kids come to play, out come my Russell Jennings and Diston D-100, after all, a good apprentice really does need to know how to correctly use hand tools first. As for the Bosch guy he didn’t lie, he was just asked about driving 100 screws, not manufactoring or long-term battery replacement, etc.

  7. Ron Ecke

    I think that we all need to remember that both a corded and cordles drill have a motor, and the energy used to wind the coils on "Both" will be relatively the same. What wasn’t addressed is how much energy is used to manufacture the "battery", versus, the "cord".
    Certainly, much more energy is used to produce a complete, cordless drill, and then more energy is used to dispose of the spent battery, so I beleive that a corded drill ultimately is more "Green".

  8. Keith Mealy

    Frankly, with the exception of a cordless drill driver, I can’t think of any tool that I’d want to own cordless. I’m never more than about 20′ from a working outlet. More power, no dead batteries, and lower Total Cost of Ownership, considering that most cordless tools are "disposable" being cheaper to replace than to re-battery. What really gets me is those $600 sets of cordless tools in a bag with one or two batteries.

    I’m anxious to see how Ridgid’s lifetime battery plan works for them. The guarantee is only as good as the company backing it up. Witness how Sears is wiggling out of their lifetime tool warranties.

  9. Thomas Owens

    There is another energy factor not touched on. Unless you unplug the battery charger after each charging, you are using energy as the transformer provides the current to charge the battery whether it is in the charger or not. The energy is being produced by the transformer 24/7. Admittedly that isn’t much but it still needs to be factored in.

    I will add my vote to the corded drills being "greener".

  10. Ron Le Couteur

    When my magnificant Sears 18v drill died, I was told the batteries would cost $80.00 each to replace, My Makita cordless suffered the same fate and its replacement batteries would not last as long as the originals until they too gave out. My cordrd models never gave out in the middle of a job and I’ve gone back that way now.

  11. Rich Greaves

    To me, the impact to the environment from cordless tools seems far greater than it could possibly be with a corded tool. As others have said, the resources required to create the battery and then the impact of the likely method of disposal mean that cordless tools will have a far greater impact on the environment. The inefficiency of cordless tools in terms of power consumption (every time we convert energy we loose some to heat) is probably less of an issue to the environment. Now if we were powering these with a portable generator instead of plugging into the wall…that’d be another story 😉

  12. Matthew

    Other than power consumption during use, one other factor that must be taken into consideration is power consumption and environmental impact during manufacturing. Corded drills cost less because they are easier to manufacture and have fewer components. The raw materials used for production of lithium batteries are primarily mined in Africa. The mining operations are displacing and threatening many already endangered wildlife. Because we are humans, it is our nature to put ourselves before the other inhabitants of the planet – especially those in far off places that we do not see or hear about. We will not stop mining these resources even if this is brought to the attention of the masses, but one thing that we can all do to lessen the impact is to recycle these batteries. The biggest lithium ion battery users are of course cell phones and laptop computers. Another intersting fact I have read about battery recycling is that whereas 98% of car batteries (lead acid) are recycled, only 2% of consumer alkaline batteries are recycled.

  13. Ron Geoffroy Sr

    Power is the question when discussing cordless vs. corded. Certainly there are certain applications that require the power received from a corded drill. Just recently I had to do some work in concrete. I attempted to use a cordless drill because of where I was working. NOT. I had to go a get my corded drill which of course gave me the constant power I needed to work through the job.
    Beyond that begs the question as put by Robert in that we would have to continue to recharge the cordless for as many time as necessary to accomplish the same job with the corded.
    Pete also brings up the production of the cordless batteries. How energy efficient or non-polluting is making the cordless batteries vs. the winding in a motor for the corded drills.
    How green are we really?
    Ron Geoffroy Sr. NH

  14. Kent McDonald

    Lets hit the Q? you posed first, the reply from Bosch is so far off the mark it is embarrassing to read it in a publication of your stature. When you are talking green you need to consider the total aspect of energy consumption and disposal of the product at end of life. On that more realistic plane the corded tool leaves the Battery powered tool so far behind you can’t see it.

    I am still using a Milwaukee 1/2" drill that I picked up used in 1973 and a 1/4" Sears I bought new in 1974. During the last ten years I have discarded at least 8 Battery powered drills/batteries/chargers. It is only recently that there are facilities to recycle the battery and then only a small portion of that.

    As to use I currently have 3 battery powered drill/drivers that are used regularly and frequently. At both my workbenches though there are corded drills permanently plugged in. Switch over to a corded drill next time you do pocket holes, it is about twice as fast.

  15. Michael Schnurr

    The other thing not mentioned here is where is the product produced and what are the effects on those who produce it? I work in Occupational Medicine and a physician I work with was telling me that a factory in China where nickel-cadmium batteries were produced was so toxic that the worker life expectancy was greatly affected. Evidently the cadmium dust was thick is the air. I think we as global consumers have to add this type of impact into our decision to buy tools, especially if it is a hobby for us.


  16. Terry Kane

    Simple application of Scientific Method!

    It should be easy enough to measure this, Glen, if you have the proper tools. First measure the power consumed by the corded drill, then measure the power consumed restoring the cordless drill’s battery to the same voltage found before running its test. Not being a working EE, I don’t know what will measure cumulative power consumption, but am confident that you can find out quickly enough. (Maybe the kids at Make magazine can help (grin) 😉

  17. Graham Hughes

    By and large I find I prefer a bit brace to any of them; I’ve never met a cordless drill that can generate half as much torque, and the only corded drills of my regular acquaintance are drill presses, really a different category of tool.

  18. Pete Owen

    Chris Friesen is right, the battery powered drill easily consumes more power than a corded drill to perform the same work. I don’t think it’s even close: there are losses when converting the 120V AC power to a lower DC voltage suitable for charging the battery (charger power supply gets warm), losses in charging the battery (it gets warm here) and losses in discharging the battery (again gets warm). Add in the disposable nature of batteries and the chemicals used to make them and it’s no contest: corded tools are more earth friendly, if not more user friendly.

  19. Pete

    I think one further aspect to consider is the production of the battery operated vs corded drills. Does the production of a battery pack create more pollution to the environment? (Granted that I don’t know either.) But you have to consider that you probably are more likely to find more cordless drills/drivers in a shop for various reasons. Power upgrades, compact size, older drills not keeping a charge, just to name a few reasons to upgrade. I myself have 4 different cordless models that has replaced one another for various reasons and one corded that has lasted me years. Has the four cordless models I have created four times the polluntion due to thier product process? That’s the question I believe needs to be answered.

    With that said, I would have to say that I would be hard pressed to give up either of my drills. They both play an important part in my workshop. Although I could survive with just a corded drill, it wouldn’t be by choice.

  20. Chris Friesen

    One thing not addressed is that there is a certain amount of inefficiency when charging a battery, and additional losses when discharging it. This energy is lost as heat, which is why the battery gets warm.

    As to your question…any time I need serious torque or lots of endurance I’ll turn to a corded drill (haven’t seen a cordless Hole-Hawg yet). On the other hand, cordless is more convenient for short jobs or where a cord would get in the way, and it’s a lot easier to get an adjustable clutch on a cordless drill/driver.

    So for me, definately both.

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