Is there a single adjective that means "does not use much energy" / "not using much energy"?

I do not mean "efficient".

Efficient means something that does not waste much energy - something efficient could use a lot of energy for a specific purpose, yet not waste much energy on actions that do not achieve that purpose/not waste energy as heat or sound or whatever.

However, something *word I seek* may or may not be efficient, i.e may waste very little, or very much energy, in trying to perform a task, but does not/will not use or consume much energy in trying to perform the task - whether some of this energy is wasted or not.

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    I tried to edit your question, but decide not to. Please read your question again and try to make it more clear using some paragraphs and deleting some redundant part.
    – user140086
    Commented Nov 23, 2016 at 11:42
  • To clarify, are you asking about energy in the physics sense, or in informal terms of effort? Commented Nov 23, 2016 at 14:49
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    Moine, you need to provide some constraints. In general, your question has no answer because energy is never consumed. But we do speak of some situations that way, particularly with respect to small machines that run on electricity or human power. Please provide a sample sentence with the type of gadget you are talking about.
    – Phil Sweet
    Commented Nov 23, 2016 at 14:50
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    I reject the premise of the question. It's all relative, remember.
    – Strawberry
    Commented Nov 23, 2016 at 16:52
  • Jeb Bush? Oh wait, its not an adjective lol.
    – 10 Replies
    Commented Nov 23, 2016 at 21:50

9 Answers 9


I suggest "economical".

"Economical" does not just mean sparing, or careful in the use of one's money. It can also apply to resources such as energy use. Use of energy can be "economical" by increased efficiency, or a higher power/input ratio. It can also just mean sparing in terms of energy use.

  • Yes, economical is good, and looking at synonyms of economical (of which there are many could give the OP what they are looking for. Frugal and parsimonous are particularly suitable.
    – JonLarby
    Commented Nov 23, 2016 at 15:26
  • With respect, but aren't 'economical' and 'frugal' synonomouse with 'efficient', which is a meaning the op is excluding? I may be wrong about the op's intent, but these adjectives describe energy use by comparative inference. A thing is economical because it spares a resource compaired to a thing that consumes the resource at a greater rate.
    – John
    Commented Nov 23, 2016 at 22:55
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    @John there's a subtle distinction. Say you're trying to make a 100-mile trip. A rocket engine can be considered efficient if it gets maximum effect out of its fuel with very little wastage, but on its lowest throttle setting it will still burn a few tonnes of fuel. A car - even a big V8 gas-guzzler - will use a lot less fuel than that, and will therefore be more economical, even though it might be a lot less efficient because a lot of the energy from that fuel is wasted. Efficiency is a proportion; economy is an absolute value. Commented Nov 24, 2016 at 10:17
  • @anaximander: Your examples are very good, but they still place the descriptor on a less/more scale, which is comparative. To me, that type of less-by-comparison is synonymous with the OP's exemption (efficient). I think, though, that you are very right. A subtle distinction is there. The OP's request, by necessity, begs comparison. Kudos!
    – John
    Commented Nov 27, 2016 at 7:21

low-power or maybe low-powered

From a physics standpoint Power = Work / Time. A low-power device does not take in much (electrical) energy. (In the end, all that energy comes out one way or the other. Often much of it as heat.)

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    It's a good answer, but one small request - since you invoked physics, can you reword the bit about uses low amounts of energy. I know the OP used the phase, but the canon in physics goes to great length to expunge that idea.
    – Phil Sweet
    Commented Nov 23, 2016 at 14:35

Energy-saving is the adjective that is generally used and that may fit your description: ​

  • relating to products, systems, etc. that use as little electricity, gas, etc. as possible:
    • an energy-saving appliance/light/product energy-saving technology/material an energy-saving initiative/measure/step

Cambridge Dictionary

  • Too close to efficient. If a task requires 1.21 gigawatts to complete but normal devices designed to perform that task use 1.7 gigawatts, then a device that uses 1.3 gigawatts would be called energy saving. There's still a lot of energy involved, even in the ideal case.
    – talrnu
    Commented Nov 23, 2016 at 18:06

low energy or low energy consumption

I replaced my old microwave oven with a low energy consumption one.

In many cases, such as the microwave, a light bulb, etc., you could say

low wattage

The landlord is so stingy he put a low wattage bulb in the entry, and now I have trouble finding the right key when I come home after dark.

If I misunderstood, and you're talking about a person, not a gadget, then I would suggest



Perhaps lethargic or languorous. But you might want to clarify the question a bit, perhaps by giving an example.


Reading your question, I take it you seek an adjective that describes an action which is preformed with little effort/will/energy/motivation/force behind it. Something not considering how efficient the action actually is, but rather how little thought it requires or how easily look it looks. If you gave a little more context, perhaps I could assist you better... Never the less, here's something in a vein of which—at the time of my writing this—others have not proposed.


" Patrick deftly grabbed an glass of champagne off of a waiter's tray as he bustled by. "

Here the word deftly describes how some guy grabbed a drink, in a fragile glass, off the tray of somebody rushing past him without spilling it or knocking all the drinks over. No easy task. Doing so would require an extreme amount of coordination and perfect timing.

When I imagine such an interaction, I don't picture some guy in a suit who is hunched over, arm outstretched, eyeing the approaching waiter like some athlete awaiting the ball. That's how I would look if attempting to grab this hypothetical champagne. (I'm terribly uncoordinated.) What I imagine is a suave gentleman who—appears to—effortlessly preform such an astounding feat without paying much attention, showing concern, of visibly displaying a large amount of effort.

Some similar words: gracefully, lithely dexterously, naturally, nimbly, instinctively, effortlessly


In french we use the words frugal and sober in that sense, but that will not fit here. May I suggest abstemious that could apply to inanimate things?

Quote from Yahoo news: we're delighted to report a new generation of trucks that are lighter, more pleasant and dramatically more abstemious draws near.

  • Please elaborate why you think your suggestion would be a fitting word.
    – Helmar
    Commented Nov 24, 2016 at 14:49

Try "unvigorous". Since vigorous means "Characterized by forceful and energetic action or activity" and you're after the opposite of that, just invert the meaning by prefixing it with "un". "Unvigorous" might not presently be in the dictionary, but perhaps it ought to be...

Other suggestions: unenergetic, lethargic, economical, thrifty

  • 1
    Welcome to EL&U. Thank you for your answer, but please tell us where did you get it. See "How do I write a good answer?" to find tips on how to write a great answer.
    – Juan M
    Commented Nov 24, 2016 at 7:48

Might I suggest, "inert"?

Lacking ability or strength to move; lacking vigor; chemically inactive.

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    Welcome to EL&U. Thank you for your answer, but please provide at least one authoritative source. Read "How do I write a good answer?" to find tips on how to write a great answer.
    – Juan M
    Commented Nov 23, 2016 at 18:02

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