The ability a physical system has to do work on other physical systems.

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3
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0answers
104 views

Are renewable energies not renewable since they depend on non-renewable materials? [closed]

This infographic paints a worrisome picture about the status of renewable energy: in order to build renewable-powered stuff we need some specific minerals, which themselves are not renewable, and so ...
15
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2answers
297 views

Does the UK has enough wind to power the country five times over?

Greenpeace UK tweeted about the UK having enough wind to power the country five times over: MT @1010: The UK has enough wind to power the country five times over. Let's use it! After a bit of ...
9
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0answers
147 views

Are powerful entities preventing the development of free or extremely low cost energy sources? [closed]

This is a common claim of people selling "free energy" devices that the government or oil companies are trying to suppress their work. I'm wondering if there's any documented examples of an oil ...
0
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0answers
132 views

Does 20 minutes of meditation equal 2 hours of sleep? [closed]

Many people claim that meditation can replace sleep. For example: Harbourside Fitness: 20 minutes of meditation is equal to 2 hours of sleep Is this true?
6
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1answer
358 views

Is a car's fuel consumption increased when the headlights are on?

I have read in many sites that a car with lights on will consume more fuel that with lights off. The (hand-waving) justifications that I see tend to mention that "energy has to come from somewhere" ...
0
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0answers
79 views

Can a car run on water? As per this experiment [duplicate]

The Agha Waqar's car that ran on water was a great news for a long time. Where a Pakistan based inventor invented a car that got all the power from water. He was using a water kit to get the energy. ...
2
votes
1answer
2k views

Does the Theradome Laser Helmet deliver around 7 J/cm2 to the head?

The Theradome Laser Helmet is claimed by its manufacturers to promote healthy hair growth. In this infographic, they claim it delivers energy to the skull at a concentration of 6.959 j/cm2 - ...
3
votes
1answer
487 views

Do photovoltaic solar panels need replacement after 20 years?

Many manufacturers of photovoltaic solar panels offer some sort of warranty that is valid for 15 to 25 years. Many people suggest that after that period of time, a replacement of the panels is ...
13
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5answers
87k views

Is this tealight-flowerpot heater more efficient than just tealights?

This article at the Daily Mail describes a small heater based on tealights and flowerpots. It claims that [the system] "make[s] the heating more efficient" (I assume in comparison to just ...
8
votes
1answer
231 views

Do lithium ion batteries double effective performance every 18 month similar to Moore's law?

On Quora a person claims that lithium ion batteries improve roughly similar to Moore's law: The installed price of lithium ion batteries is dropping in half every 18 months and they last twice as ...
2
votes
2answers
759 views

How long does it take for renewable technology to recoup its energy cost?

There are a number of technologies which are aimed at producing energy from non-fossil sources, among which very popular are wind power and solar power technologies. However, I have encountered a ...
2
votes
1answer
319 views

Is Gasification of Garbage a Viable Energy Solution?

I read this NYT article about using blast furnaces to turn garbage into burnable gas, yielding a net energy output. The article suggests that the company, Sierra Energy, is very close to building a ...
8
votes
2answers
389 views

Do ad blockers in browsers save significant energy?

There is a claim that adverts sometimes include animations, which requires more energy to display, and that, hence, ad blockers save significant energy? Source: Blocking Online Ads May Save Energy ...
6
votes
0answers
97 views

Has a carbon price lead to a 8.6 percent drop in electricity demand in Australia?

In a press release China’s pilot carbon trading market taps UNSW expertise (press release is by the UNSW, which is my employer) Minister Combet highlighted the benefits to date of Australia’s ...
10
votes
2answers
2k views

Are wind turbines harmful to human health?

The so-called wind turbine syndrome has received quite a bit of attention of late. For example, on How Stuff Works: Until recently, there were three main issues regarding the possible downsides of ...
4
votes
1answer
266 views

Is Australia the highest per capita emitter of greenhouse gases in the OECD?

The Australian earth hour web site claims that Australia is the highest greenhouse gas emitter per capita in the OECD. I've also heard this claim elsewhere. DID YOU KNOW… Australia is the highest ...
4
votes
2answers
3k views

Does painting your radiators black make your heating more efficient?

I have heard that painting radiators in your central heating circuit black can make your heating more efficient. The 'scientific' basis being that black, whilst absorbing light in the visible ...
24
votes
2answers
8k views

Is there any data on how efficient Tesla wireless power transmission was?

It's widely believed that Nikola Tesla not only demonstrated wireless power transmission but his works in this field were very successful. Wikipedia only says this The electric energy transmitted ...
22
votes
1answer
4k views

Did/does the US government keep secret papers by Nikola Tesla?

A popular conspiracy theory holds that Tesla invented a free energy device, but that the powers that be prevented him from publishing it, because it would hurt their investments. Of course, free ...
10
votes
3answers
12k views

Can permanent magnets be exploited to create energy?

There are many videos on youtube in which permanent magnets are used to make a motor. Although it might be possible in an ideal environment (e.g. no friction). As these devices are rotating ...
14
votes
2answers
1k views

Do wind turbines kill many birds each year?

It has been claimed that due to their large size, and the velocity of their blades that wind turbines kill large numbers of birds that run into them at night, or in fog, and die. ...
2
votes
1answer
2k views

Are 2–4 hour washing machine programs eco friendly?

New washing machine (at least in the EU) often have a special program named with something like "green" or "eco" and that are supposed to be environmentally friendly. These are often for around 2–4 ...
15
votes
1answer
5k views

Does keeping a fridge or freezer full improve its energy usage?

It's sometimes cited that a full fridge or freezer helps reduce its overall energy usage (for example, this source says so, based on the amount of cold air that 'can escape' when you open the door). ...
1
vote
0answers
124 views

Are radiator reflectors as effective as claimed? [closed]

I asked this very same question over on home improvements and it was suggested that I ask it here. I am considering using radiator reflectors at home to help improve the efficiency of the central ...
13
votes
1answer
591 views

Is each step in the food chain 10% efficient?

I remember learning in school many years ago that each level of the food chain is only about 10% efficient. So when an herbivore eats a plant, they get 10% of the energy that the plant had, and a ...
30
votes
2answers
5k views

Is the “wind lens” a breakthrough in wind energy?

In this video a "brim" is placed around a wind turbine and the power generated doubles. A simple static mechanism that doubles the efficiency of a turbine seems too good to be true. Is this a ...
9
votes
2answers
679 views

Are electric cars beneficial to the environment compared to low consumption modern cars?

Imagine an electric car in a country where most energy come from coal (which i believe is the dirtiest). Add this to the pollution that disposing the batteries will create, or the carbon footprint ...
28
votes
2answers
1k views

Which baby diaper is more Earth-friendly — cloth or disposable?

We have a lot of friends who use cloth diapers, and I've heard some say that cloth diapers are actually more un-ecologically friendly than disposable diapers. I have a hard time buying that. I can ...
16
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2answers
1k views

Does the digestion of some foods burn more calories than it supplies?

Calories in food is a measurement of the amount of energy it will provide to the body. I've heard that eating some foods actually make you USE more calories than you consume. Do any foods actually ...
6
votes
0answers
269 views

Are electric cars better for the environment than internal-combustion cars? [duplicate]

Possible Duplicate: Does a car with a hybrid engine and Lithium batteries pollute more than a car with conventional technology? We hear a lot about electric cars being the future. But we ...
32
votes
2answers
27k views

Can you recharge non-rechargeable alkaline batteries?

There are conflicting reports of whether it is possible to safely recharge alkaline batteries (not lithium) that are not sold as rechargable. The packaging for batteries regularly has cautions ...
11
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2answers
526 views

Solar energy in place of conventional energy sources

The first time I came across these arguments against solar energy was in "Overload" by Arthur Hailey. Admittedly, this is fiction, but the arguments seems to have some merit. Using solar cells to ...
13
votes
1answer
841 views

Can thorium end the energy crisis?

It seems that, as of lately thorium is steadily increasing in popularity, as an alternative to traditional nuclear fuels. Here's Mr. Kirk Sorensen in a TED video advocating the use of thorium. ...
128
votes
4answers
16k views

Does a webpage with a black background save energy?

Blackle is a search engine that claims to save energy because it uses a black background. Is there any evidence to back up their claim that a website using a black background will save energy, and if ...
4
votes
1answer
927 views

Is the Rossi Focardi LENR true?

Italian inventor Andrea Rossi claims to have discovered cold fusion. There is a history of dis-proven discoveries in this area. How were they debunked and are the arguments applicable to the new case ...
14
votes
2answers
366 views

Are CFLs always more ecologic than incandescent light bulbs?

Incandescent light bulbs are now being phased out in many countries. In practice, the replacements are mostly compact fluorescent lamps (CFL). In many cases, the energy savings created by CFLs justify ...
4
votes
1answer
1k views

Did Tesla say that one could get or transmit energy through thin air [duplicate]

Possible Duplicate: Can you create energy out of nowhere ? I recall reading that Nikola Tesla suggested that electricity could be created from the air. This claim is stated in the following ...
15
votes
2answers
444 views

Is the net output of CO₂ from Nuclear Energy lower than the net output of other energy sources?

While CO₂ is not produced directly when producing electricity from nuclear power, it is obvious that obtaining the radioactive material and preparing it for its use in a plant inevitably produces some ...
22
votes
2answers
6k views

Is nuclear fusion energy as safe as its proponents claim?

With my limited knowledge of the process of nuclear fusion energy, this seems like one of the most promising methods for producing huge amounts of energy, with relatively very low risk, once ...
17
votes
5answers
2k views

Are there fewer accidental deaths at nuclear power plants than others?

I have seen the stats on this website saying that the number of death caused by nuclear accidents was way smaller then those caused by any other energy production factory. Do you have any information, ...
11
votes
1answer
311 views

Can drilling for geothermal energy trigger a major earthquake?

I remember reading about this geothermal project being cancelled due to concerns over (relatively) small seismic events caused by the drilling. Have there been any instances of, or reasonable ...
18
votes
7answers
4k views

Are there technologies that provide unlimited free energy?

Many different sources claim to be able to produce "unlimited free energy". For example: UNLIMITED FREE ENERGY IDENTIFIED Company claims to have developed new technology that provides unlimited free ...