The percentage ratio of energy produced to energy supplied to a system; or a measure of minimum energy required relative to energy actually consumed; or a measure of relative energy consumed to provide the same energy service.
Questions tagged [energy-efficiency]
133 questions
8
votes
1 answer
Does repeatedly turning on and off an appliance tend to damage it?
When nobody is watching the TV, my practice is to turn it off, so as to save electricity, even if I know that someone will want to watch it in the next 10 minutes.
However, it is claimed that turning it off and then on again 10 minutes later is…
user1631
5
votes
1 answer
Which US university has done the most to reduce GHG?
Which US universities, either public or private, have programs that have shown quantitative reductions in GHG emitted? In fact I would like to see universities "bridge the gap" between themselves and their "real-world" neighbors, so I am going to…
Jack Ryan
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5
votes
2 answers
Home owner doesn't care about house having insulation
I'm renting a home with central heating and air conditioning in Oklahoma. It's really hot now (90 inside) so I have the A/C on all day but it's cold at night because the attic has no insulation and the owner isn't interested in installing any. I'm…
sandra overly
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4
votes
1 answer
How much energy am I harvesting?
I've developed a water pump that is powered by a 1 watt solar air pump. In 24 hours it pumps 54 gallons to a height of 30 feet. How much energy have I harvested?
Anthony Scotti
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3
votes
1 answer
Why is there no energy star certification for portable or box fans?
Why are there no energy star certifications for portable fans?
From what I understand no portable electric heaters have the certification because using a portable heater is not efficient at all.
Ceiling fans and ventilation fans are certified;…
Agriculturist
- 133
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3
votes
0 answers
Are there toasters with a selector for one or two slices?
I noticed that all toasters I could find (even the ridiculously expensive ones, 300 Euro/dollars) toast both slots at the same time, instead of offering a selector one/two.
The closest I could find one expensive brand offering individual slices at…
FarO
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2
votes
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What 'average' conditions are used to test the energy usage of freezers for a EU energy label?
I'm orienting myself on buying an extra (small) freezer on top of the limited amount of freezer space I already have in my fridge/freezer combination, so I can more easily cook and store fresh produce that usually comes in 'big' portions, like…
Tinkeringbell
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