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18 votes
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What to do with old, unused incandescent light bulbs

TLDR; don't use them for lighting. Given that you could keep your incandescent bulbs for when your current energy-efficient (I will assume CCFL) bulbs need replacing, your choice boils down to: buy a ...
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14 votes

Which solar power technology has the highest energy return on investment (EROI aka EROEI)?

TLDR; cadmium telluride panels have the highest EROI of the mentioned PV panels (around 34.2) EROI estimates vary widely. This is because of differences in the method of calculation, scope of the ...
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13 votes

What form of electrical lighting has the smallest energy-footprint?

i signed up just so i could make this comment. THelper♦ provided a good link to a DOE report on this topic, which i was researching because my roommate is skeptical about the advantages of efficient ...
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12 votes
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Do switchable sockets left "on" use electricity if there's nothing plugged in?

No. With nothing plugged in there is no circuit, so no current can flow. An exception to this is if the socket or the switch has an indicator light - usually a neon one - that is illuminated when ...
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11 votes

What to do with old, unused incandescent light bulbs

I use them in garden/indoor. Something like this... (source : google search)
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11 votes
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What is the most sustainable way of making coffee?

I live off-grid, so I did a lot of study on this topic. All used coffee grounds make good fertilizer. Drip machines seem to use a lot of energy, and they seem to use it for a lot of time. They also ...
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11 votes

Getting power from an innovative new mechanism

No, you cannot get more energy out than you put in. No, you cannot invent a perpetual motion machine.
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10 votes
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Can pumped water energy storage be combined with rainwater harvesting?

Water loss is not the issue, because you need a lot of water to make it work at all. Even if your dams lose 30% of their water every year, that's about 0.1% per day. System losses in the best large-...
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9 votes

How much wood can I burn sustainably, carbon neutral and in an ecologically responsible way from a forest?

Well, I'm by no means an expert on giving this answer, and yet I'll take a go at providing something reasonable. Assuming a 1ha biodiverse, properly hydrated, young stage forest with optimal leaf ...
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9 votes
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When transporting high-end food stuff from Chita to Moscow, which method is more fuel efficient, by rail or by air?

Air is much more energy intensive. Gucwa and Schaefer looked at the impact of scale on energy intensity in freight transportation, and the chart below is taken from that paper. They looked at varying ...
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9 votes

What to do with old, unused incandescent light bulbs

I disagree with the answers that say not to use it. It may in fact be an excellent idea to use it if: you live somewhere that requires your home to be heated in the winter you currently heat with ...
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  • 1,777
9 votes

Should I replace existing inefficient light bulbs?

Sort of. Consider the pay back time. high efficiency lights are expensive. Expense is, at least in part, a measure of the resources used to make it.* Replacing the fixtures in the kitchen where the ...
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8 votes

Lowering the heating thermostat at night: is it really worth it?

tl;dr: Yes, lowering the room thermostat at night will generally help save energy, assuming we are in the heating season (winter), rather than the cooling season (summer). Let's take two points in ...
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8 votes

Do USB outlets waste energy just like conventional wall warts?

Electronically they're the same and will waste as much energy as a conventional adaptor. Depending on your electrical regulations they may be forced to be at the good end of adaptor efficiency, or ...
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  • 2,037
8 votes

Is leaving the fridge door open for, say, 10 seconds a "big deal"?

It is common knowledge that hot air rises and cold air sinks. Inside a fridge the coldest air will be in the bottom of the fridge. As soon as the fridge door is opened cold air from the bottom of the ...
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  • 3,152
8 votes
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Laptop nights: shutdown or sleep?

To determine the power used when the computer is in sleep mode you can acquire a power meter that plugs into a power outlet & measures the electricity used by devices that are connected to the ...
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8 votes
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Does transporting plastic offset the benefits of recycling it?

tl;dr: No, shipping plastic waste to China for recycling does not offset the benefits, as it reduces the net energy savings by 3% or less. Polyethylene, The most common plastic According to ...
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7 votes

What is the difference between "hydro" and "tidal/wave"? And what is the difference between "solar (heat)" and "solar panels"?

Beware that chart - it is from 2004, and hence is very out of date! In particular, photovoltaics ("solar panels") have become cheaper much faster than anybody expected a decade ago, and wave and tidal ...
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  • 3,601
7 votes

What is the number 1 country by global installed wind capacity: the United States or China?

According to the REN21 Renewables Global Status Report 2014, China had 91.4 GW of installed wind capacity by the end of 2013, more than any other country in the world, of which 75.5 GW was in ...
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  • 14.6k
7 votes

What to do with old, unused incandescent light bulbs

Please consider donating incandescent bulbs to a support group for diseases that can sensitize some people to light. One disease with fairly widespread support group chapters is Lupus. Lupus has ...
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7 votes

How much energy could we save if we all got up at sunrise

The best analogy for this is the use of daylight savings time, where in effect people wake up one hour early than they usually do. A study by the US Department of Transport in 1975 (see page 4 of the ...
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  • 3,152
7 votes

Why the world is using non renewable resources?

There is no one reason for why humans are using non-renewable resources like fossil fuels and nuclear fuels to generate energy. I'll write what I know about and others can do the same and from all the ...
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  • 3,152
7 votes

Electrical usage data logging with wireless data transfer

It sounds like the Kill A Watt wireless might be what you are after. For more alternatives keep reading. There is another product line called the Watts-Up that has USB connections to computers on ...
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7 votes

Is pellet fuel a sustainable energy source in the way it's used now?

It depends. It is possible to farm wood sustainably, or unsustainably. Both ways happen now. It is possible to use wood pellets for energy while trapping particulate matter and other non-GHG ...
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  • 14.6k
7 votes

What is the most sustainable way of making coffee?

Your grinder may be less efficient than a commercial unit, and shipping beans rather than ground coffee may affect the bulk for shipping. If you use extra (hot) water in washing a permanent filter you ...
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  • 2,037
7 votes

How much energy do wall outlets with USB waste when not actively charging?

In most countries, legislation limits the amount of power a device on standby, i.e. under power but not performing a function, are allowed to use. In Europe it's 0.5 Watts (see EC Regulation No. 1275/...
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  • 161
7 votes

What should I do with coal that I have been given?

Well, if you are really into it and quite handy, you could turn it into activated charcoal, and then add it to your soil! Grind it into small bits, heat it anaerobically, then introduce high-pressure ...
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6 votes

How can I determine whether roof top wind turbines would be beneficial in my area?

One approach is to look for studies in this area and decide whether the idea is even plausible. Is it "a bit more expensive but I like the technology" or is it "much more expensive and ...
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  • 3,755
6 votes

What to do with old, unused incandescent light bulbs

Osram did a good comparative life cycle assessment on bulbs, including incandescent, CFLs, and LEDs. The total life cycle impacts of CFLs and LEDs are both significantly lesser in all categories than ...
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6 votes

What to do with old, unused incandescent light bulbs

What to do with existing stock of incandescent bulbs – use them up or just put an LED in any socket where a lamp burns out? As efficient LED bulbs are widely available the question comes up what is ...
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