General Questions
Do things use energy when they're turned off?
I've heard several times that toaster ovens use electricity even when they're off. Is that true? -- Matthew A., Berkeley, CA, 2-01
Not unless it has a clock of some kind, and I've never seen a toaster oven with one. You can use the How to measure electrical use section to test for yourself whether your toaster oven is drawing current or not when it's off.
Some devices like microwaves & VCR's draw a small amount to power the time display, often 5 watts or less. Devices which run off transformers also draw a small amount of power, typically 1-5W. There's more about this on our page about stuff that uses energy even when it's off. You can find out how much any device uses, even when it's off, on our How to Measure Energy Use page.
If an appliance is turned off but the wall switch is left on does this use electricity? -- Alison P., 5-01
Not usually, but some devices draw a small amount of current for standby power, as explained on our Standby Power page.
If you turn on the switch to operate a lamp, and the lamp has no light bulb, does it consume any electricity? -- Karla P., 7-03
No, it doesn't. Same as if it has a light bulb that's burned out -- no energy used.
I remember wondering about this myself when I was a kid. Little did I know I would grow up to answer that very question on the Internet.
I also used to wonder if you turned the radio off and
turned it back on later, would it pick up where it left off?
I heard that an electrical wiring problem can lead to electricity "leaking" out of the wires and into the abyss, causing a person to pay for electricity that they don't use. -- Kathie T., 9-08
Yes, this is a possible. Note that on an
earlier version of this page, I mistakenly listed this one as
a Myth, but an electrician corrected me. When the wiring
isn't connected correctly, it is indeed possible for
electricity to "leak". The electrician who contacted me
had a customer with a $15/mo. leak due to faulty wiring.
On another page I have detailed
instructions on how to check for this kind of electricity
leak.
Besides mis-wiring, you could also have undersized
wiring, where the wiring is too thin to handle the load being
driven. When that happens the wiring heats up. The
extra heat generated represents wasted energy, but more
importantly, the extra heat can cause a fire which can burn
your house down. If you have a modern home which had an
electrical inspection when it was built then it's unlikely
that your wiring is inadequate. But if you have an older
home or your wiring was never inspected when installed, it's
possible that your wiring isn't sufficient for what you're
running through it. Unfortunately this isn't the kind of
thing you can easily test yourself. That's a job for a
competent electrician.
Other General Questions & Comments
I think you're misleading people. The real savings to be had is by turning off things that run all the time, like computers, and things that use standby power. Affecting [sic] real change on big appliances etc. is expensive, and hard to do with very long paybacks. This encourages apathy and besides, in all those cases, the device is usually doing something useful, cooling, heating, etc. What I learned and recommend is to make your list by time-on, forget doing all the calculations or measuring of watts and getting confused between watts and kilowatts and kilowatt hours. If you quit giving people the wrong info they wont need to ask so many questions. -- Mark R., April 2009
Thanks for dissing my life's work. In any event, the answer to part of your complaint is that you're not reading carefully, and the other part is that you're simply wrong.
- It's bizarre that you're chastising me for not focusing on
standby power. Besides the fact that I
do cover standby power and list eight separate ways
to reduce it, I also point out that it's only 5% of a
home's energy use for most people. That is, it uses less
energy than just about anything else in the average home. As
you can see in the pie chart (which appears throughout the
site), there are huge savings to be had in most areas other
than standby power. I would be irresponsible if I insisted
that people chase the least important item to them,
which is what you want me to do.
As for computers, my computers page does recommend that people sleep their computers, and I've said so for years.
- Looking only at time-on is wrong because some things use a
lot more energy than others. A 2.5-ton central AC system
uses 700 times as much energy as a device in standby that
uses only 5 watts. Total energy is the rate of consumption times
the amount of time the item is on. You have to look at both.
You can't look at simply one or the other. That's why my electricity
calculator accounts for both the energy rate and the
amount of time the item is on.
- Effecting big change in appliances is not
expensive or difficult. It takes no effort to wash your
clothes in cold water instead of hot. It takes little effort
to turn off the AC and use a ceiling fan instead. It takes
little effort to use space heaters only in the rooms you're
using rather than trying to heat your whole house. I have
tons of practical tips on my heating,
cooling, lighting,
and other pages, all of which work, and many of which are
decidedly easy to implement.
- I explain what watts, kilowatts, and
kilowatt-hours are because some people want to
know. And in any event, just like if you want to save
money you have to know what a dollar is, if you want to save
electricity it's helpful to know what a kilowatt-hour is.
Can you explain in detail how you only use 160 kilowatt-hours a month? -- Caroline B., May 2005
Good question! Here's my rough estimate.
6 kWh |
15-watt CFL light in my home office, on 12 hours a day every day (15 watts x 12 h x 30.43 d) |
117 kWh |
Ancient refrigerator (from my refrigerators page (1400 kWh/yr. divided by 12 months) |
15 kWh |
Ceiling fan (28 watts x 18 hours/day x 30.43 days) |
17 kWh |
Computer system (100 watts x 8 hours x 21 days) |
5 kWh |
Cooking (750-watt burner x 0.3 hours x 21 days) |
160 kWh |
Total |
[Note: In 2007 I finally replaced my ancient refrigerator and now I use only about 94 kWh/mo. in typical months.]
I do use a bit more in the winter, for my electric space heater.
How are we actually saving the electricity in our house and where is this saved electricity stored when we are not using it? Don't the electricity power generators keep on generating electicity all the day? -- Jagadish H., April 2005
Yes, the generators run 24/7, but when you use more electricity, the generators have to burn more fuel. When you switch off the lights, the generators need less fuel. If you were powering some lightbulbs with a stationary bicycle, it would take you a lot more effort to power five light bulbs than one. The generator works the same way. Most electricity in the U.S. is made by burning coal, which is extremely polluting, so the less electricity you use, the less coal is burned. That's why saving electricity is such a powerful way to reduce pollution (especially climate-change gases).
You asked where the saved electricity is "stored". The answer is that it's stored in the coal or other fuels that didn't have to be burned because you used less electricity than normal.
(Special thanks to Kurt Vey, a master electrician working at a utility substation, who corrected an error in my original answer.)
I want to generate all my own power with solar and live "off the grid". I'd like to connect with other people have done this who might have expertise to share. Where do I find them?
You'll find them at Off-Grid.net.
Though the question does not apply exclusively to electricity, I am wondering with all the technology available to humans today why we are so slow to switch or adapt to other ways of producing electricty or heat. Surely with all the inventions in the last century, are governments spending enough money on research for alternative energy applications? Or is there just too much money to be made from regular methods. ie power plants hydro electric dams etc.? -- Hugh, Feb. 2005
You're assuming that we have the capability of discovering or inventing some other cheap form of energy. Most observers think this is unlikely. The research hasn't been ignored, you just don't hear about it because it hasn't been very productive.
In just a few years there will be an economic meltdown as we reach the peak of global oil production. Every year after that we'll produce less oil than the year prior, which will have devasting effects worldwide. There's more about this at Life After the Oil Crash and OilCrisis.com.
There are energy saving devices in the market that promise up to 15% savings on your electric bill. You simply plug it into any wall outlet. Do such devices really work? One such device is at: [dead link]. -- Fernand, Pasay City, Philippines, Jan. 2005
There is no such thing as a "plug-it-in-and-save" device. It's like trying to lose weight without changing what you eat or how much you exercise. Saving electricity actually takes some effort; you actually have to turn off stuff when you're not using it. You can't just be lazy and plug in some device and forget about it.
I also hoped it would be obvious that if any such device really worked I would list it on this site. Does it make sense to you that I would create this mega website about saving electricity but somehow decide not to mention a device that saves energy by simply plugging it into the wall?
About the specific device you were asking about, what should jump out off the page at you is that their website has zero technical information about how their product supposedly works. In fact, in their FAQ section they have this:
Q: Is there any prove [sic] to show us that this device 100 percent can help us reduce our electrical bill?
A: Yes, we have a test report carried out by PSB(Singapore) which we will show to u.
Hello? If they have such a report why isn't it published on their website? And why are they writing like they're some teenager on MySpace?
Finally, does it not ring any bells at all that they don't even have their own domain name? This supposedly legitimate energy-saving company is sponging an address off 1tuition.com.
I went ahead and wrote to them requesting a unit to review and not surprisingly they refused to send one. If a company that sells an alleged electricity saver doesn't want the #1 site in Google for "saving electricity" and "how to save electricity" to review their product then that alone ought to tell you something. [Update: Their website is now down. They didn't stay in business long -- not surprisingly.]
Here's more about why power factor devices don't save energy and why surge supressor devices don't save energy.
When the power goes out could I get emergency power from my car by connecting an inverter to the battery and running a 12-gauge extension cord to my house? It seems much cheaper than spending $550 for a gas powered generator, and my car always has at least 10 gallons of gas. Of course, I would leave the garage door open so I would not die. -- J. V. W., Saint George, UT, Dec. 2004
Your question isn't really about saving electricity so you're kind of pushing it, but let's look at this anyway because it's interesting.
There are three basic ways to get emergency electrical power when the electricity goes out. Each of these devices has a regular outlet that you can plug your electrical devices (or a power strip) into. Here's how they compare:
|
|
(battery+inverter) |
|
Cost |
|
|
plus several thousand for the car |
Maximum Instantaneous Power |
|
|
700 watts (direct to battery) |
Watt-Hours |
|
|
|
Maximum Run Time |
|
|
|
Downsides |
Highest cost, noisy (especially cheaper models), storage for a big piece of equpment, gas can't be stored for more than a couple of months (according to HowStuffWorks.com) |
Provides the least amount of total power in watt-hours. Kind of pricey. |
Inefficient, provides the smallest amount of instantaneous power. But is the cheapest solution, and provides plenty of power in watt-hours. |
* Assumes 10 gallons, and that car runs for 1 hr. per gallon of gas, which is a rough guess. |
I cringe at the thought of running a car to generate household electricity because it's so inefficient, but it definitely has the cheapest entry cost (if you exclude the price of the car) and most convenient method (if you already have a car).
By the way, don't even think about connecting the output from one of these to your household wiring. You'd be in for a nasty surprise when the electricity comes back on.
How much coal is required to generate enough electricity for a day in an average home? -- Jonathan, Seward, NE, Dec. 2004
Coal accounts for 52% of electricity generated in the U.S., as it says on the front page of our site. The average home uses 920 kWh a month, as it says on the What's a Kilowatt? page. It takes 2.25 lbs. of coal to make 1 kWh of electricity.
So one month's worth of electricity is
|
|
|
|
|
|
x 52% |
= 1076 lbs./mo. |
|
|
|
|
That would be 35 lbs. a day, or 12,917 lbs. a year.
The calculator listed on the front page of this site will tell you how much pollution (sulphur dioxide, volatile organic compounds, etc.) is caused by your electrical use.
Incidentally, the figures available from Baywinds suggest that 0.03 therms of natural gas contains the same amount of energy as one kWh of electricity.
I live in a large co-op complex where our electricity costs are included as part of the rent. This means that those of us who conserve don't get to pay any less, and those who are wasteful don't pay any more. We are now considering whether to move to electrical submetering which would enable us to retain the cheaper bulk rates we have now, yet have each resident pay his/her own electric bill. Needless to say this is very controversial. The pro-submetering residents (including me) argue that by just engaging in very basic conservation measures (like not leaving lights/ac on all day when you are at work), the average resident would pay the same or less in monthly costs. The anti-submetering contingent (who generally belong to the leave lights/ac on all day while at work population) has put forth several very emotional arguments, like suggesting that the sizable number of senior citizens in our complex would suffer the financial burden most since they are home much of the day and presumably use more electricity. My gut tells me that's not so -- most seniors live alone, and don't have/use electrical gadgets (computers, stereo equipment, video games, hair dryers, etc. etc.) in the same amount as younger residents/families would. My feeling is also during the summer although they might use the AC more hours since they are home, seniors probably by and large don't try and keep their apartments as cool as younger people/people with families would because they would probably feel too cold in those temperatures. Any facts/suggestions you can come up with? I am assigned to write a flyer about submetering in an attempt to convince people it's a GOOD thing. Since this is a cooperative, shareholders must vote on whether we go with submetering or not. Thank you for any help you can offer. -- Julie B. , NYC, Nov. 2004
It's funny you mentioned co-ops -- I lived in some housing co-ops and I just got back from speaking at a national co-op conference. I also have a website with helpful articles about managing student housing co-ops. But let's get to your electricity issue.
First of all, you're absolutely right -- when the electricity is given away in an "all you can eat" fashion then why would anyone save? Making people pay for what they use is the only way people will use less. And it's fairer, because right now people like you are paying a higher rate because others choose to be wasteful. Incidentally, I've encouraged our local student co-op student housing co-op to stop including electricity as part of room rates for that very reason.
But knowing that you're right doesn't solve your problem. How can you convince the others that this is a good idea? My feeling is that if the arguments are based on emotion or if they're just plain unreasonable then confronting them with facts isn't going to help any. To prove your point I think you're going to have to put your money where your mouth is: If you're certain that elders won't have to pay more under the new plan, then suggest that elders' bills be capped at whatever the current rate is. That way you no longer have to prove that seniors wouldn't have to pay more, because you've made that an impossibility. How could they still object after that?
Be sure to write back to let me know how the vote goes.
I just wanted to let you know your web site has a wealth of information, thank you so much. Also, do you know if there is an invention that can cut down the amount of electricity you are using, for example: my TV, VCR, DVD and stereo are plugged into a strip, which is then plugged into the wall, is there anything that the strip could plug into before it's plugged into the wall to defer the amount of energy it's using? I've looked around and found surge protectors but it's not what I was looking for. -- Nikki, Oct. 2004
For electronics equipment, no. Obviously if such a thing existed I would list it on this site. Since the whole point of this site is to share energy-saving info, if such a device existed why would I keep it a secret?
In any event, these devices aren't nearly the biggest energy hogs in your home. You'll save a lot more energy by switching to compact fluorescent light bulbs, and addressing your heating and cooling costs.
I note that in the US you have a 110-120 volt system whereas ours in Britain is 240 volts. Does this have any bearing on how much power identical appliances use in the two countries? James D., Nov. 2002
Good question. Despite the difference voltage, energy use is the same. You use more volts, but you also use less amps, so it evens out. For example, in the U.S. a device might use 120 volts x 2 amps = 240 watts. In Britain, that same device would use 240 volts x 1 amp = 240 watts. So energy use is the same.
And of course, costs are the same, because you're charged by the kilowatt-hour, not by voltage. (Well, the costs won't be exactly the same, because there's a different price for electricity in Britain....)
What about those devices that are supposed to save energy by increasing the "power factor" and reducing the need for "reactive power".
They don't work for residential customers. See
my separate page on Power Factor.
I was shocked to find you could run 200 ceiling fans using the same amount of power needed to run one electric clothes dryer. Don't you think last years rolling blackouts could have been avoided if only clothes dryer use was cut in half? Most Californians live in desert, which means their clothes would dry fast if nature was give half a chance. Are any of the Home Associations overturning their ridiculous clothesline bans?
Do you know California's current kWh cost? About how much would it cost a family of 6 to use their clothes dryer everyday for one hour in LA? Over $30 a month, no? Considering the rolling blackouts cost California's economy billions, the real number could be doubled. Californians are unscrewing around, changing 100 watt light bulbs to 40. Saving 600 kWh if they change 10. A family of 6 could save 45,000 kWh just by cutting their clothes dryer use in half! Si or No?
Is there any place else I could visit to learn more about saving electricity in California? Muchisimo Gracias, Lance A. Boyle, May 2002
Actually, you could run 200 to 800 ceiling fans with the electricity required to run a clothes dryer. Ceiling fans are just really efficient, and electric clothes dryers are just huge energy hogs, simple as that. If only more people knew, or cared...
I don't follow California homeowners codes or the CA cost per kWh. But as a wild guess, if we said Californians paid $0.15/kWh, then 5 kWh/day x 30 days/mo. x $0.15 = $22.50, not far from your figure. If you're in California, look on your electric bill or call your utility company.
There is no question that rolling blackouts could have been avoided if Californians cut their dryer use in half. Heck, it would only take something like a 10% reduction in electrical use across the country to shut down half of the nuclear power plants.
Your comparison of savings for changing lights vs. less clothes dryer use doesn't seem to be accurate. First of all, switching from ten 100-watt bulbs to ten 40-watt bulbs saves 600 watt-hours, not 600 kilowatt-hours. Second, that savings is for every hour the lights are on, though you seem to assume that the lights will be on for just one hour a day. Finally, cutting dryer use in half doesn't save 45,000 kWh: an hour a day for an electric clothes dryer is 5 kWh x 365 days/yr = 1825 kWH/yr. Cutting that use in half would be 912 kWh/year. By comparison, saving 0.6 kWh from changing 10 light bulbs x 8 hours/day x 365 days/yr = 1752 kWh, far more than cutting electric dryer use in half.
As for where else you can find info on saving electricity, aren't the gazillion suggestions on my website enough to keep you busy for several months?
U.S. Voltage
your site constantly claims US power is 120, or 240, this is not correct. US power is 110, or 220 (commonly only used for major appliances or industrial applications. ... aside from working with an electrician for several years, you made me have to get on yahoo and do YOUR research for you. [quotes a few non-reliable sources, including a Geocities site (!) and something called the "End Times Report"] -- Joe R., February 2008
No, U.S. residential voltage is truly 120/240. To prove this you can simply stick a watt-hour meter into the wall and read the voltage. I've done this with countless outlets across the U.S. And if you prefer to believe what you find on the Internet rather than what your own eyes tell you, you could at least pick better sources. For 120 & 240V mentioned together, try Popular Mechanics, Consumer Reports, Good Housekeeping, the city of Phoenix, AZ, and Kenmore. For 120V alone see PowerStream and the University of Georgia. For 240V alone there's the California Energy Commission.