the sustainable use of energy, through efficiency and renewables. Use this tag for questions on energy in general. For questions on a specific energy type see [electricity], [heating] or [light]. For questions specificially about efficiency, use [energy-efficiency]

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Gas and Oil Production? [on hold]

Does Oil companies care about the environment within their race for achieving a rewardable profit ? What is the price and Who will pay pack?
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4answers
161 views

What is the most sustainable way of making coffee?

Which method of brewing coffee is the most sustainable? The criteria being: minimal waste, minimal energy (no matter where it's produced) I guess for the optimal solution it would be necessary ...
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3answers
102 views

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

Pellet fuel is considered a sustainable energy source. But the way it's used now seems to produce air pollution which I think should not happen in case of sustainable energy source. So is pellet ...
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2answers
113 views

Would you save energy by heating the air in a shower stall so that you could use colder water?

It is refreshing to take a cool shower in hot weather. And for the sake of discussion, lets assume that one should be "comfortable" with temeratures when taking a shower. Considering that the vast ...
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1answer
103 views

Electrical usage data logging with wireless data transfer

Does anyone know of a wireless energy usage capture device, that one can attach to an appliance and find out the energy usage? I know that there are certain energy monitors that do the job to some ...
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2answers
218 views

Do USB outlets waste energy just like conventional wall warts?

It is widely known that most AC-DC converters (aka "wall warts") continually use electricity, even when no devices are plugged in to them. That wasted energy is often called "phantom electricity" or ...
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1answer
118 views

Can artificial lighting compete with horizontal agriculture?

Background In Professor Bugbee's presentation, he describes some drawbacks of vertical farming (VF) versus traditional horizontal agriculture. Most of Bugbee's arguments against VF hinge on grow lamp ...
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52 views

How effective are “GreenUp” (opt-in utility company green energy) programs?

My local Seattle utility offers a "Green Up!" program where customers can pay extra on each bill to buy energy from more renewable sources. I'm signed up to contribute at the highest level ...
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1answer
286 views

Should I leave water in a water boiler for prolonged periods?

When I fill my electric water boiler with water some time before boiling it, the water gets warmer, it's temperature get closer to the room's temperature, saving some energy. On the other hand, I've ...
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2answers
68 views

Is there a way to tell (or estimate) the electricity consumption of an arbitrary household item?

I often wonder how much energy a given item in my home is using. Examples include: the clock on my microwave my espresso maker an electric water kettle my phone charger (when no device is attached) ...
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3answers
266 views

Why the world is using non renewable resources?

According to Wiki, A renewable resource is an organic natural resource which can replenish to overcome usage and consumption, either through biological reproduction or other naturally recurring ...
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1answer
189 views

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

Just had a thought: How much energy could be saved if everyone got up at sunrise? Perhaps it would have a counteractive effect somehow but my thought is that if you're up less during hours that it's ...
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6answers
3k views

What to do with old, unused incandescent light bulbs

Over the years, my family has built up a small stockpile of incandescent light bulbs. More recently, we have been replacing our incandescent lights with more energy-efficient alternatives. ...
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1answer
62 views

Is there an “energy returned on materials invested” index for energy sources?

We already try to measure how much energy is invested (EROEI) in the production of energy, but I have a hard time finding numbers on the materials invested. For example: What is the total energy a ...
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1answer
47 views

What is the carbon footprint of energy transfer across power lines?

I've been doing some reading up on the full cycle carbon footprint of energy production and consumption, and realising there's a lot of aspects that are frequently overlooked. One of these I'm ...
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2answers
229 views

Less energy consumption when we stop using fossil fuels?

What's the best way to find out how much less energy we would use if we would quit fossil fuel usage altogether? What would be the percentage entailed? I know it's easy to find out with electrical ...
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2answers
98 views

When transporting high-end food stuff from Chita to Moscow, which method is more fuel efficient, by rail or by air?

Chita is a Russian city nestled between Mongolia and Manchuria. Although Chita is located on the trans-siberian railway, I wonder if it is more energy efficient to ship 100 tons of cut beef every day ...
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1answer
173 views

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

In the following graph: We see that China surpassed every single country in wind energy production, except the United States. But these statistics are up to 2009 only. So my question is: what about ...
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4answers
3k views

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

In the following graph: What is the difference between "hydro" and "tidal/wave"? And what is the difference between "solar (heat)" and "solar panels"?
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2answers
67 views

Sustainability of wood pellet sources for biomass boiler

We're considering a biomass boiler for our guesthouse (1820 vintage with corresponding energy issues). The opportunity to reduce gas usage and the economics of the RHI scheme in the UK (a sort-of ...
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1answer
168 views

Best way to dry hands

In our office toilets at work we have paper towels and a hand dryer. Is it better for the environment to use the towels or the dryer?
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1answer
614 views

Do switchable sockets left “on” use electricity if there's nothing plugged in?

My flat is fitted with switchable sockets as per below: Please settle an argument a friend and I are having: if a socket is switched "on", is it wasting electricity if nothing is actually plugged ...
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6answers
304 views

How can I use my own body as an energy source for greater environmental sustainability?

I've had the epiphany that my body is a living vessel of energy production (and consumption), just like all other energy sources and associated forms of consumption or re-allocation around me. My ...
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0answers
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What kind of population-to-agriculture relationship is the most sustainable? [closed]

City/Rural Relationship High concentration of humans and low concentration of agriculture that are largely fed by areas outside the city that are very low in human population but are very high in ...
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1answer
101 views

Is building vertically instead of horizontally in climate with large seasonal temperature changes more sustainable?

My main line of thinking would be that you would build tall skinny housing that would allow the heat to gather in the upper levels in the winter and the cooler air would gather in the basement/lowest ...
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4answers
310 views

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

I've heard some very conflicting information regarding the effect of lowering the house heating thermostat at night. On one hand there are academic papers (such as Thermostat strategies impact on ...
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1answer
134 views

Relative carbon footprint of gas or electric heating (UK)

Inspired by this question: Given the current UK (2014) generation mix, would changing a house from gas to electric heating increase or decrease its carbon footprint? The original question was about ...
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1answer
156 views

Reducing the setpoint by 1 degree C will save 7% energy: what's the origin of that claim?

I often hear a claim saying that reducing the thermostat's setpoint by one degree C will reduce the overall yearly energy consumption by 7%. I've heard heating control manufacturers, energy ...
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1answer
83 views

Synthetic Propane Manufacture

Methane (CH4) is available naturally. Propane (C3H8) is derived from Methane. Is there a process for synthesizing propane applicable to a micro-farm environment?
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1answer
130 views

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

While wood can - in theory - be a carbon neutral fuel, in practice burning wood creates a huge carbon debt and it may take a long time for all the carbon released by logging, soil degradation and so ...
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2answers
107 views

Is canned fish more sustainable than fresh?

I read this beauty-oriented article claiming that canned fish is more sustainable than fresh fish. Is this true? Listed below is a brief energy/sustainability brain dump on the subject. Canned fish: ...
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1answer
186 views

Is opening windows wide or opening them slightly more efficient for exchanging air in a room on a cold day?

For those who wish to replace the air in a room during a cold day with active heating: Given that the purpose of opening the windows is to exchange as much of the air in the room as possible with the ...
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4answers
140 views

Retrofitting insulation in a 4-storey home. Top down or bottom up?

I'm faced with the prospect of wanting to improve the insulation of a 4-storey Victorian (c1890) house in the UK that has solid stone walls and a top floor that is within the non-insulated roof space. ...
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3answers
107 views

Resources for Teaching Children About Solar Panels

I'm sure some of you will have already taken classes on Solar. The reason I am posting this question is to help out two Farmers in Kauai, Hawaii. They are currently creating an extension program ...
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2answers
494 views

Solar energy concentration using cylindrical Fresnel lenses

What are the advantages and disadvantages of using cylindrical Fresnel lenses as PV concentrators? My goal is to do some research and see which kind of Fresnel lenses are better to concentrate light ...
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2answers
150 views

Challenges of providing sustainable energy sources to meet future demand in Ireland

what are the main challenges Ireland faces as regards providing sustainable energy sources to meet future energy demand?
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2answers
263 views

Can an enclosed Pelton Turbine be used as a pump?

Can an enclosed Pelton Turbine be used as a pump, perhaps through the centrifugal forces created in a enclosed Pelton Turbine when it rotates at speed? The water striking out of the buckets of a ...
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3answers
40k views

Which type of portable electric heater is better?

When one is buying a portable electric heater, there are at least three different types available: Radiative halogen heaters Fan heaters Oil-filled radiators and similar Images of examples of each ...
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1answer
183 views

Should payback periods take the time value of money into account?

I am currently reviewing a paper estimating the payback period for different building renovation strategies. The calculations I see typically go something like this: you pay (say) USD 3000 today, ...
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3answers
408 views

Cost-effective alternative to rechargeable batteries?

Batteries are known to be the most unsustainable and expensive part of system exploiting renewable energy. So I am wondering, are there any alternatives to storing energy in batteries? Here I am ...
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2answers
910 views

Are power plants more efficient than typical gas-powered car?

For the last couple weeks, I've been hearing a lot of talk surrounding Tesla and "the electric car". What I'm curious of is whether or not it is more efficient to actually power an electric car (the ...
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4answers
230 views

Water heating / electricity production by using earth's warmth?

I'm very curious, why hasn't anyone done this? In most places on earth, the temperature gets 25 degrees higher (celsius) for every kilometer in depth. How hard would it be to drill 4-5km, put a ...
6
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1answer
450 views

Are tracking mounts cost-effective for home photovoltaic systems?

Solar PV panels are clearly more efficient at converting sunlight to electricity if they are mounted on racks that rotate to track the sun's apparent travel across the sky. However, tracking mounts ...
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1answer
1k views

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

Which solar-electric technology had the highest EROEI? Energy Returned On (Energy) Invested, also known as EROI and as EROEI, has become something of a fashionable metric *but see footnote. It is ...
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2answers
416 views

Want to build a portable solar refrigerator

I've got a 5v Peltier chip. What kind of and how many solar cells 4.5v 18mA do I need per 1 chip? I found these cells online on dealextreme, but there are also other different types. I'm lacking a ...
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965 views

How much energy does it take to create a single light bulb?

This question is a part of this question. Perhaps it is better suited on the physics SE, but here goes. I would like to know how much energy it takes, in the modern world, to construct an ordinary, ...
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4answers
541 views

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

We all know that when it comes to household electrical lighting, LED lights consume the least amount of energy for a given amount of light, followed by fluorescent tubes, halogens, and Edison-age ...
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2answers
407 views

Tea in the microwave

I occasionally need exactly a cup of water boiled for tea. Whenever I boil the kettle to do so, I wonder if it would be more energy efficient to use the microwave, as then I would have exactly the ...
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5answers
3k views

Does a dishwasher save water in the long term?

I've been considering a dishwasher, but there are a range of different opinions on if they save water (or even energy) or not. Do we have any sources one way or the other?
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5answers
450 views

What is worse: Wasting water or energy?

I am currently trying to buy a dish washer and just got a washing machine lately and I am really confused whether it is better to buy a machine which uses less water or one which uses less energy. ...