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Questions tagged [energy-efficiency]

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19
votes
2answers
897 views

Do “smart meters” bring about any significant savings?

UK television stations are showing multiple commercials such as this one which make claims about making significant savings if you get a smart meter (the linked ad claims fitting a smart meter would ...
49
votes
3answers
12k views

Can the US be powered by a 100 miles x 100 miles solar grid? [duplicate]

In this article Elon Musk is quoted to say that the US can be powered by a solar grid shaped as a square (in video he says "a corner of Utah or Nevada") 100 miles x 100 miles big. “If you wanted ...
6
votes
1answer
1k views

Does Leonardo DiCaprio fly on private jets?

Does Leonardo DiCaprio fly on private jets? Example claim: Leonardo DiCaprio flies 8,000 miles in private jet to accept ‘green award' Oscar-winner Leonardo DiCaprio flew an additional 8,000 miles ...
5
votes
0answers
550 views

Does the 3M mouse pad extend battery life up to 50% or 75%?

The 3M company has a product called 3M™ Precise™ Mouse Pad with Repositionable Adhesive Backing and Battery Saving Design, MP200PS that claims to: Battery saving design extends battery life of ...
4
votes
1answer
793 views

Can Hemp free us from oil dependency?

Within this article it makes the claim that hemp oil is a viable alternative to crude oil. It doesn't go into any detail. It only states that hemp oil is a "clean fuel" while listing in the title "...
5
votes
1answer
426 views

Any scientific evidence that bubble wrap on windows lowers energy bills?

These newspaper articles claim that bubble wrap is an effective window insulator: The Telegraph Cheap and effective: using bubble wrap on the inside of your windows will help reduce energy bills ...
6
votes
1answer
397 views

Does Shell's “Nitrogen enriched” gas have positive effects?

Shell gas stations here in Canada claim to be "nitrogen enriched"; WHY SHOULD YOU USE SHELL NITROGEN ENRICHED GASOLINE? It is the only gasoline that contains the patented and exclusive Shell ...
16
votes
1answer
506 views

Do setback thermostats cause more energy to be used, and does the heating type matter?

It was first brought to my attention by a local HVAC Contracting company, that a programmable/setback thermostat would actually cause my home heating system to use more energy, and hence for me to ...
0
votes
0answers
22 views

Does leaving the fan on during an RV a/c cycle time save energy? [duplicate]

When running an RV a/c during the summer, is it more energy-efficient to let the fan run while the compressor is cycling? Does it cause more wear and tear? Does it even matter if you allow the fan to ...
41
votes
1answer
6k views

Does a human on a bicycle travel more efficiently than any other species?

Steve Jobs claimed on video that a bicycling human is more efficient at locomotion than any other species can manage. He repeated it separately on video, and in writing. The quote is still oft ...
14
votes
1answer
968 views

Does a deep freezer use more energy when there is a layer of ice in it?

In light of the potential upcoming power shortages in Belgium, there are a lot of "tips" going around to save power during the cold months. One of them is to thaw out the ice in the deep freezer as, ...
11
votes
1answer
611 views

Do calcified water heaters use more energy?

It is very often claimed (by both government energy efficiency experts and water-heater sellers/service people) that calcified heating elements in electrical water heaters lead to much higher energy ...
17
votes
1answer
967 views

Are claims about saving power by turning appliances off instead of leaving them in standby accurate?

I keep hearing this argument that if you powered down all the appliances you normally leave on standby (TV, hifi, set top box, DVD/Blu ray player, computer, etc) you'll save nearly £90 a year in ...
5
votes
1answer
268 views

Did Volkswagen, Chrysler and/or GM cut diesel tailpipe emissions by ~99% over a decade?

This article, dated Jan 5, 2014, makes a rather vague claim that Companies such as Volkswagen AG, Chrysler Group and General Motors have invested billions to make that happen, outfitting vehicles ...
8
votes
0answers
2k views

Is it more environmentally friendly to stir hot drinks with pasta?

In the café where I work, somebody tried introducing pasta, spaghetti in particular, in place of purpose-made wooden sticks, for stirring hot drinks, as it was thought to be more "environmentally ...
6
votes
1answer
840 views

Do fluorescent lights use more power to turn on?

I have been told time after time that at school if you are not going to leave the room for more than 10 minutes to keep the lights on instead of turning them off because the amount of power it takes ...
30
votes
2answers
2k views

Does the phase-out of incandescent light bulbs measurably reduce overall electrical power consumption?

Many countries are phasing out incandescent light bulbs. For example, in the European Union, various types of classic light bulbs have been removed from the market in the last years. The claim is ...
7
votes
2answers
2k 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 ...
5
votes
1answer
958 views

Does a Geyser Blanket save electricity?

In South Africa a "geyser" is a type of water heater that typically consists of a cylindrical water tank of 100 to 200 Litres capacity heated by an electric heating element of 2kW to 4kW capacity. A ...
13
votes
1answer
5k views

Are ion heaters significantly more efficient then normal electric heaters?

An ion heater manufacturer claims their ion heaters are a lot more efficient than common electric heaters: How ion boilers (heaters) STAFOR can reach COP 1,57? In solid conductors only half (...
10
votes
1answer
2k views

Do candles emit ten times the carbon dioxide of an equivalent lightbulb?

In Wasteful Earth Hour?, it's claimed that candles emit roughly 10 times the carbon dioxide of light bulbs of the same brightness. While emissions will vary depending on the candle, the lightbulb and ...
9
votes
1answer
688 views

Can an on-the-fly water electrolyzer linked to the air intake improve fuel efficiency of a gasoline engine?

This article initially seems to investigate so-called water powered cars. The final few paragraphs of the article however branches off into discussion about a system where (as I understand it): A car'...
58
votes
3answers
105k views

Does a mobile phone charger that is plugged in but has no phone attached to it use energy?

Obviously, I am talking about simple charger without any indicator lights etc. If yes, why does it use energy when the circuit is not closed? Examples of the claim: http://www.treehugger.com/culture/...
12
votes
1answer
16k views

Are insulating window films worth it?

I'm curious if tests have been conducted to evaluate the energy efficiency gains and resultant savings produced by insulating window films like these 3M Window Insulator Kits. (There are also films ...
20
votes
1answer
7k views

Does driving a car in a lorry's slipstream increase fuel economy?

On UK roads, I frequently see cars driving very closely behind larger vehicles, attempting to stay in their slipstream, reduce drag and thus increase fuel efficiency. Given the dangers of driving so ...
17
votes
1answer
1k views

Are Hummers more environmentally friendly than Prius?

I've heard this rumor a few times (example). The argument is that it takes energy to make the car, and when you take into account how long each car will last on the road, driving Prius's over a large ...