# what are those electricity saving device thingies? **URL:** \ **Category:** Factual Questions\ **Created:** [September 1, 2007, 2:47pm UTC](https://boards.straightdope.com/t/what-are-those-electricity-saving-device-thingies/417724 "2007-09-01T14:47:09Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![shijinn](https://avatars.discourse-cdn.com/v4/letter/s/cc9497/32.png) [@shijinn](https://boards.straightdope.com/u/shijinn)\ **Post date:** [September 1, 2007, 2:47pm UTC](https://boards.straightdope.com/t/what-are-those-electricity-saving-device-thingies/417724/1 "2007-09-01T14:47:09Z")
recently there was this door to door salesman who tried to sell me a device that supposedly reduces my electricity bill, like a battery or something. he did a demonstration and it appears to work, according to his handheld meter. i didn’t like him however, so i turned down his exclusive, one time offer and tried to look up the device on the net instead. turns out the product’s website looks iffy, and is in fact incomplete. i’d like to know more about the product since my electricity bill is pretty high. what are the things called? do they work? is it some sort of scam? ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [September 1, 2007, 2:52pm UTC](https://boards.straightdope.com/t/what-are-those-electricity-saving-device-thingies/417724/2 "2007-09-01T14:52:23Z")
Link to the product’s website? ---
**Author:** ![shijinn](https://avatars.discourse-cdn.com/v4/letter/s/cc9497/32.png) [@shijinn](https://boards.straightdope.com/u/shijinn)\ **Post date:** [September 1, 2007, 3:18pm UTC](https://boards.straightdope.com/t/what-are-those-electricity-saving-device-thingies/417724/3 "2007-09-01T15:18:29Z")
oh. here it is [http://www.enersavetech.com.sg/products.php](http://www.enersavetech.com.sg/products.php). it’s the “Residental Bank”. the link on the page doesn’t seem to be working. ---
**Author:** ![David\_Simmons](https://avatars.discourse-cdn.com/v4/letter/d/9de053/32.png) [@David\_Simmons](https://boards.straightdope.com/u/David_Simmons)\ **Post date:** [September 1, 2007, 3:27pm UTC](https://boards.straightdope.com/t/what-are-those-electricity-saving-device-thingies/417724/4 "2007-09-01T15:27:57Z")
[QUOTE=shijinn] recently there was this door to door salesman who tried to sell me a device that supposedly reduces my electricity bill, like a battery or something. he did a demonstration and it appears to work, according to his handheld meter. i didn’t like him however, so i turned down his exclusive, one time offer and tried to look up the device on the net instead. turns out the product’s website looks iffy, and is in fact incomplete. i’d like to know more about the product since my electricity bill is pretty high. what are the things called? do they work? is it some sort of scam? [/QUOTE] Sales talk or no, you still can’t get something for nothing. Once an electrical appliance is designed and built (and bought) there is no way to reduce the power input for a given output or the energy consumed. Most such devices merely reduce the reactive line current thus giving the appearance of saving power but they don’t. The current that they reduce is ignored by your electric meter and doesn’t cost you anything other than the energy lost by that reactive current in the wiring resistance. If you undersood that latter bit, great. if you didn’t just take my word for it and save your money for something else. If you want to reduce you electric bill, use flourescent bulbs and turn them off when not in use. Buy efficient appliances. In other words, follow the advice you can get from you utility on how to reduce your energy use. ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [September 1, 2007, 3:33pm UTC](https://boards.straightdope.com/t/what-are-those-electricity-saving-device-thingies/417724/5 "2007-09-01T15:33:07Z")
[QUOTE=shijinn] it’s the “Residental Bank”. the link on the page doesn’t seem to be working. [/QUOTE] Sounds like a version of one of [these](http://www.power-save1200.com/faqs.html): > [@](#): > > The Power-Save 1200™ Unit reduces the amount of power drawn from the utility by storing (in its capacitors) otherwise lost electricity (watts) caused by the inductive motors in your home. (Some examples of inductive motors are Air Conditioning units, refrigerators, freezers, washers, dryers, dishwashers, pool pumps, vacuum cleaners, furnace blower motors, fans etc.) The technology applied by the Power-Save 1200™ Unit supplies that stored electricity back to your inductive loads, thus causing you to decrease your demand from the utility. ---
**Author:** ![David\_Simmons](https://avatars.discourse-cdn.com/v4/letter/d/9de053/32.png) [@David\_Simmons](https://boards.straightdope.com/u/David_Simmons)\ **Post date:** [September 2, 2007, 12:55am UTC](https://boards.straightdope.com/t/what-are-those-electricity-saving-device-thingies/417724/6 "2007-09-02T00:55:36Z")
Also from **Squink’s** cite. > [@](#): > > What is Power Factor? > Power factor is the percentage of electricity that’s delivered to your house and used effectively, compared to what is wasted. For example, a 1.0 power factor means that all the electricity that’s being delivered to your home is being used effectively for its purpose. However, most homes in North America today have a .77 power factor or less. This means that 77% of the electricity that is coming thru your meter at your home or business is being used effectively, the other 23% is being wasted by your inductive load. With a low power factor, the utility has to deliver more electricity to do the same work. However, the Power-Save 1200™ increases that power factor in most cases to .97 or .98, thus increasing the effective use of your electricity and lowering your usage. Total bullshit. A power factor of 0.77 does not mean that for every 100 watts, or watt hours, you pay for you only get the benefit of 77. What is delivered to your meter is volt-amperes which is the product of voltage times current. Volt-amperes is made up of two parts, watts and reactive volt-amperes. Your electric meter responds only to the watts and disregards the reactive volt-amperes. I should mention that the utility wants a unity power factor to reduce line losses. The line losses are proportional to the square of the line current and unity power factor gives the least current in the line. Utilities like unity power factor so much that they go to the trouble of hanging capacitors all over their system to get as close to unity as possible. ---
**Author:** ![David\_Simmons](https://avatars.discourse-cdn.com/v4/letter/d/9de053/32.png) [@David\_Simmons](https://boards.straightdope.com/u/David_Simmons)\ **Post date:** [September 2, 2007, 1:24am UTC](https://boards.straightdope.com/t/what-are-those-electricity-saving-device-thingies/417724/7 "2007-09-02T01:24:14Z")
P.S. There aughtta be a law. ---
**Author:** ![MyglassISfull](https://avatars.discourse-cdn.com/v4/letter/m/bbce88/32.png) [@MyglassISfull](https://boards.straightdope.com/u/MyglassISfull)\ **Post date:** [September 2, 2007, 2:11am UTC](https://boards.straightdope.com/t/what-are-those-electricity-saving-device-thingies/417724/8 "2007-09-02T02:11:23Z")
Only have lights/machines turned on where you’re at, ie if you’re not upstairs/outdoors don’t have the lights/tv/computer on there? Plus insulate your loft. ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [September 2, 2007, 3:28am UTC](https://boards.straightdope.com/t/what-are-those-electricity-saving-device-thingies/417724/9 "2007-09-02T03:28:46Z")
**David Simmons** is right, as usual. Is it a PFC device? If so, here’s the deal: If you install a PFC device at your home’s breaker panel, the only one who will benefit will be the power company. Why? Because the device will make the impedance of your home - which has a resistive & reactive component - “look” like a purely resistive load (or very close to it) from the perspective of the power company. The power company likes this, since it means it won’t have to pay for the I[sup]2[/sup]R loss in the power lines that are created by the reactive component in your house. Now… if a PFC device is installed somewhere in your house at the load, it _does_ have some benefit to you (in addition to the power company), since there will be less I[sup]2[/sup]R loss in your home’s wiring (which you would otherwise pay for). But for most loads, the benefit will be so small that it’s probably not worth it. Suffice to say, it’s basically a scam. At least for home owners. ---
**Author:** ![David\_Simmons](https://avatars.discourse-cdn.com/v4/letter/d/9de053/32.png) [@David\_Simmons](https://boards.straightdope.com/u/David_Simmons)\ **Post date:** [September 2, 2007, 4:56am UTC](https://boards.straightdope.com/t/what-are-those-electricity-saving-device-thingies/417724/10 "2007-09-02T04:56:13Z")
[QUOTE=Crafter\_Man] \*\*Suffice to say, it’s basically a scam. At least for home owners. [/QUOTE] Even industrial users who benefit from power factor correction don’t benefit much from the reduction in wiring losses within their plant. The benefit is that the power company gives them a cheaper rate. In effect the power company shares some of the savings in their line loss with the customer. ---
**Author:** ![shijinn](https://avatars.discourse-cdn.com/v4/letter/s/cc9497/32.png) [@shijinn](https://boards.straightdope.com/u/shijinn)\ **Post date:** [September 2, 2007, 9:39am UTC](https://boards.straightdope.com/t/what-are-those-electricity-saving-device-thingies/417724/11 "2007-09-02T09:39:29Z")
[QUOTE=David Simmons] … Most such devices merely reduce the reactive line current thus giving the appearance of saving power but they don’t. The current that they reduce is ignored by your electric meter and doesn’t cost you anything other than the energy lost by that reactive current in the wiring resistance. … [/QUOTE] i see. his meter was measuring something my electric meter ignores.. thanks for the replies. so basically they’re legally selling something _completely_ useless without fear of repercussions? the thing isn’t even pretty enough to be a paperweight. =\ ---
**Author:** ![essell](https://avatars.discourse-cdn.com/v4/letter/e/34f0e0/32.png) [@essell](https://boards.straightdope.com/u/essell)\ **Post date:** [September 2, 2007, 10:42am UTC](https://boards.straightdope.com/t/what-are-those-electricity-saving-device-thingies/417724/12 "2007-09-02T10:42:44Z")
Previous [Thread](http://boards.straightdope.com/sdmb/showthread.php?t=427449&highlight=inductive+motors) on the topic. With extra confusing science!