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Questions tagged [electricity]

Questions concerning the production or use of electricity in a sustainable way.

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3answers
159 views

Why are my LED light bulbs so short lived?

I thought the idea of LED is, that the light bulb has a very long life and uses very little electricity. I have not invested in full LED lighting but tried the LED bulbs, you screw in your normal ...
3
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6answers
179 views

better to heat house with gas or with electricity?

Is it better to heat house with gas or electricity? We have gas insert and gas heating but am looking at other options for sustainable energy use. Thank you!
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1answer
128 views

How much energy would it cost to stabilize 2 tons of water at 70 degrees?

I'm trying to figure out the efficiency of energy usage between heating up 2 tons of water from 5°C to 70°C everyday (during winter) within a certain given time (let's say one hour) and stabilizing 2 ...
3
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1answer
138 views

Is Tesla Powerwall a good investment?

I'm trying to determine if investing in a couple of Tesla Powerwall units to store solar energy is a wise financial decision. My energy cost is $0.1649/kWh. The installed price of the two Powerwall ...
5
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3answers
53k views

How many kilowatt hours of electricity does it take to heat 180 litres of water from 15 to 60 degrees C?

I think this calculation uses the specific heat capacity for water, which is from memory a bit over 4. Can someone please do the math? Also, if we assume electricity costs $0.30 per kilowatt hour, ...
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2answers
115 views

Differences in efficiency between oven, toaster oven, and stove?

Wondering how efficient different cooking methods are (for the sake of example, assume a dish in a cast iron pot heated by stovetop vs. oven). Stove seems to use less energy than an oven (as the ...
5
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2answers
3k views

Which is more energy efficient, a washing machine express wash, or normal?

My electric washing machine has an express wash button (they seem a common feature) that reduces the washing time by a lot. My first thought would be that using it would save energy because of the ...
21
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3answers
3k 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
31 views

Are pure or modified sine inverters different?

Just starting my power closet to power my off grid mobile home I've come to question everyone that I belive would know with no concrete answer Is there a difference between using a modified sine or ...
3
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2answers
821 views

How much electric energy would a studio apartment use per month if everything inside is powered by electricity (heater, water, stove, etc.)

How much electric energy, on average, would a typical one-person studio apartment consume per month in the winter if everything inside is powered by electricity? Additional Information: Apartment ...
5
votes
1answer
51 views

Size and reliability of inverter for refrigerator in an off-grid tiny home

I am building an 'Off Grid' tiny home, with my primary energy supply from solar + battery storage. I intend to utilise low voltage everything possible with the exception of a standard home washing ...
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3answers
2k 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 ...
4
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1answer
109 views

How much, if any, does resolution effect the net power consumption of watching online video?

I watch a lot of online video. I'd assume that for example videos on Youtube in 720p use less power than the same videos in 1080p. I think this might be because: more power is used by sending network ...
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4answers
230 views

Getting power from an innovative new mechanism

I am new to StackExchange and trying my best to stay within the rules. I have invented an efficient mechanism -- a rotating mass magnetically attached inside a closed loop (GB 2517244). I am ...
5
votes
1answer
119 views

Best course of study for learning to build electrical systems and supporting electronics for an off grid power station

I'm working on constructing a totally self sufficient (i.e. totally off grid) building in the wild. I do not want to restrict myself to any particular source of power (hydro, solar, wind etc), but I ...
7
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1answer
353 views

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

In new buildings and homes I've noticed wall outlets with USB chargers popping up more and more: Answers at another question indicate that these outlets waste energy just like traditional chargers ("...
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3answers
2k views

What's the average efficiency of pumped hydroelectric energy storage facilities?

Pumped hydroelectric storage has, to date, been the most scalable way to store electricity (in this case, in the form of gravitational potential energy), allowing us to spread the time between when ...
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5answers
18k 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
3k views

Is leaving an electric oven on to heat bad for the oven?

We leave our oven on with door open to heat our trailer Will that cause the ovens thermostat go out it's an electric stove with four burners to boil water also for heat.
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3answers
107 views

Do higher electricity prices cause people to use less?

Demand for gas is elastic... I've read that cars in Europe are, on average, more efficient than cars in the US due to significantly higher taxes on gasoline. ...but not for electricity? In the ...
33
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3answers
3k views

Are electric cars as environmentally friendly as we think they are?

Given the fact that the average lifetime for a car battery is 3 years and all of the batteries end up at a landfill at the end of their lifetime, how sustainable are electric cars in providing a ...
23
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10answers
758 views

How can I manage my fridge's contents better?

Sadly, about 30-50% of the Western world's food is thrown away. Personally, I waste about half of my food, due to poor fridge management. I forget what I have bought and find expired food located in ...
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1answer
53 views

Office building electricity use [closed]

A typical office lease says the tenant has 1.5 watts of electricity to use per sq.ft. for lighting and 3.5 watts of electricity per sq.ft to use for computers etc. anything over this they say extra ...
4
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1answer
71 views

How can I find out what a reasonable rate for installed solar is?

I'm looking to have a ~20kW grid-tied solar system installed at our property in Ontario, Canada. I've been searching and reading but am unable to find current (last year or two) data on how much such ...
9
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3answers
131 views

How the grid is managed in markets with high renewable energy penetration

As many people know, many of the renewable energy technologies generate fluctuating power dependent on availability of the power generating source e.g. wind and solar et al. Balancing power must be ...
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6answers
820 views

Producing my own energy options in urban area with windows but no roof access?

I'm wanting to produce my own energy, but I live in a condo with no access to the roof. I'd like to produce electricity, so maybe turning that energy into electricity safely. I have windows that have ...
7
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1answer
191 views

Can 140 square miles of solar panels power the US?

In the book The Upcycle (copyright 2013) by William McDonough and Michael Braungart, the authors make the following claim: ... consider exactly how much desert area covered in solar collectors ...
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5answers
13k views

What types of plugged in electronics use energy even when turned off?

I just need some convincing before I start unplugging everything. I kind of assumed that USB type computer, phone, or printer chargers would use electricity. And obviously my computer, sound system, ...
7
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2answers
266 views

Anything similar to GravityLight that can be readily purchased?

Ever since it was first mentioned in a popular news site, I've always been interested in GravityLight. But I've never been able to go to a store or a site and just buy it. Is there anything vaguely ...
7
votes
2answers
884 views

Can I connect an inverter directly after an MPPT controller, with no battery?

Is it possible to connect a 12VDC to 220VAC inverter to the output of an MPPT solar charge controller, with no battery? This will be cheaper than having a full solar inverter, which can be really ...
4
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3answers
430 views

Does the price of polysilicon (for solar PV panels) depend on oil prices?

The assertion that the answer to this question is "yes" was made in an answer to another question here: Which solar power technology has the highest energy return on investment (EROI aka EROEI)?. The ...
1
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1answer
223 views

Does a PV panel take more energy to build than it generates in its lifetime? [duplicate]

Industrial energy costs are $1 per million BTU (MMBTU) or 300kWh, or $3*10^-6 per watt hour (Wh). http://www.eia.gov/consumption/manufacturing/ Solar has 1 kg of 9n silicon per 100W, at $20/kg. ...
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4answers
770 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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8answers
2k views

What is an easy way to cool off during the summer without electricity?

What are some easy ways to stay cool during the day without using electricity?
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2answers
90 views

The more miles a car drives, the more economical battery packs become?

I was reading here: Here’s How Electric Cars Will Cause the Next Oil Crisis, that the more miles an EV drives, the more economical battery packs become. I don't understand this assertion. I see ...
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3answers
10k views

How to build a waterfall powered electric generator?

Want to build one of those old-style water wheels powered by a waterfall. Is there a more efficient way than the ones that were around since the start of the industrial revolution?
9
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2answers
142 views

Does it make any difference to charge my electronic devices using an USB port?

I work with a computer and I was wondering if using its USB ports to charge the devices that I use the most (mostly my phone and my e-reader) while working as opposed to charging them using a normal ...
4
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1answer
156 views

Energy requirements for sustainable food production system

Overview Consider the following system for sustainable food production: The purpose of this system is to provide an environmentally-friendly, semi- (or fully-) automated means to produce food for ...
5
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1answer
365 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 ...
5
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1answer
105 views

Hydro-electric generation from roof-collected rainwater

Can electricity be produced from running water by the use of dc motors? For example rainwater collected from from the roof of a very tall house say 15m high is directed through a pipe and at it's exit,...
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4answers
198 views

Why are electrical cars encouraged but is electrical heating discouraged?

Electrical cars are very much promoted for a sustainable future, because they do not rely (directly) on fossil fuels. In the meantime, most of the electricity is produced with fossil fuels, such that ...
5
votes
3answers
131 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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3answers
1k views

What Makes an Oven Eco-Friendly?

I am currently in the market for ovens and I wanted to know what makes on oven eco-friendly, whether it's electric or steam, without compromising reliability. I want a oven that not only benefits me ...
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3answers
6k views

Would monocrystalline or polycrystalline solar panels perform best in a UK climate?

If I were to get solar panels installed on the roof of my home, in the UK, what type should I choose? There appear to be three main types, and at present the choice appears to be between the ...
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2answers
80 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) ...
7
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2answers
628 views

What are the physical limits on wind turbine size?

Wind turbines just seem to keep growing. Predictions a few years ago that a 120-metre diameter rotor was going to be the maximum, have turned out to be wrong, and 154-metre rotors are being installed ...
2
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1answer
47 views

Coupling a solar DNI dataset with demand loads at different time zones

This question is about analyzing the potential of concentrating solar power (CSP) to meet different load curves, each load curve at one time zone. I would like to know the best way to analyze the ...
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2answers
123 views

How would one go about judging the sustainability of BitCoin or other cryptocurrency

I know BitCoin uses a lot of electricity for its mining, but how is this comparable to the banking system? Also, other cryptocurrencies, like PeerCoin, claim to be more environmentally friendly by ...
6
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1answer
109 views

What is the global environmental impact of holiday decorations?

Just a random curiosity question here. How much do all the holiday lights and other such decorations affect the environment? Relative to the footprint of a house a set of outdoor lights is probably ...
7
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1answer
257 views

Transmit solar over multiple time-zones?

I heard that at big voltages (10 000+V) the energy loss along a wire is very small. Unfortunately I've got little electrical knowledge, but this sparked up a question: Considering that peak ...