19 votes
Accepted

For electricity use, which is better: Turning all appliances on at the same time, or spread out?

The "surge" that the electric utility was referring to is the demand charge: The kWh charge (consumption) is the measurement of the amount of energy the building uses over the given period ...
  • 11.5k
13 votes
Accepted

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 ...
  • 3,659
10 votes
Accepted

How much power does an idle PC use?

The problem here is that there is really no such thing as an "average desktop". There are a lot of factors that influence this, and just "averaging them out" doesn't really work. Your university may ...
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 ...
8 votes

Which is more energy efficient? Heating ten 1L water separately or one 10L water directly

Unless she's actually using the 1-2 litres of tea each time, there's more savings from simply boiling less water. We bought a small electric kettle with a flat bottom and glass walls to encourage ...
  • 3,785
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 ...
  • 2,047
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 ...
6 votes

For electricity use, which is better: Turning all appliances on at the same time, or spread out?

The primary issue being described is Peak Demand charge. The description in LShaver's answer explains a lot of that, but there are a few more pieces that I think are important: Why does peak demand ...
5 votes

How much energy does it take to store 1 Terabyte of data in the cloud?

According to a 2016 blog post by Backblaze, a (particular) 1.5TB HDD uses 3.4W when idle and 5.9W when operating. This gives a lower bound of 20 kWh / TB / year and an upper bound of 35 kWh / TB / ...
5 votes

Is it better to leave your computer on?

It undoubtedly uses more energy to leave a computer on than to turn it off. A PC will draw a few hundred Watts when on, compared to a few Watts powered down but plugged in. The biggest hardware ...
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5 votes

How much power does an idle PC use?

If you come across this answer and have measured your idle system's power consumption please extend the list by editing this answer or adding a comment. Power Consumption Measured by Users Power ...
5 votes
Accepted

How much energy costs do portable solar panels save in a house?

I'm afraid these little mini solar kits are much smaller in scale than rooftop panels. They can be great for charging gadgets when away from mains electricity, but they're not an economic substitute. ...
  • 3,659
5 votes

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

"Is there no significant consequence to how we use our bodies' own generated energy - from a resources sustainability point of view - or are there considerations one can put into use in terms of ...
5 votes

Which is more energy efficient? Heating ten 1L water separately or one 10L water directly

The heat loss will be proportional to the surface area. If you boil ten litres, one litre at a time (rather than all ten litres at once), there's typically a lot more surface area, so the heat loss ...
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4 votes

How much energy costs do portable solar panels save in a house?

The Goal Zero PV panel is rated at 20 Watts. Specifications here Here is the average insolation figures for Houston The line in the 4th chart titled "Insolation, kWh/m²/day" gives the kWh per square ...
4 votes

Do USB outlets waste energy just like conventional wall warts?

If you are looking for an efficient USB outlet, this post refers to a USB wall outlet that shuts off when not plugged in.
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4 votes

How to reduce energy usage of refrigerator while away?

Some models have a holiday mode which can be used with care. On a fridge-freezer it often stops cooling the fridge compartment (AEG) or at least stops cooling it enough to keep food fresh. Check the ...
  • 2,047
4 votes
Accepted

What is marginal energy?

What is marginal energy, or fuel on the margin? Fuel on the margin, when talking about the electric grid, refers to which fuel will be used to generate the next additional kilowatt of power that is ...
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4 votes

For electricity use, which is better: Turning all appliances on at the same time, or spread out?

The company was having problems with demand pricing as discussed in other answers. That's not a problem for residences (usually). At a "micro" level on the grid, it doesn't matter. You ...
3 votes

Are crypto currencies sustainable?

The cryptos that require large/increasing/exponential amount of processing power/electricity to function are not sustainable according to the (resource-related) meaning of the word. If, however, we ...
  • 2,774
3 votes

Is an incrementalist approach to decarbonisation feasible?

This Zero Carbon Britain report gives a detailed answer to your question. Their plan sees emissions being reduced to 8% of the current levels, and the rest being balanced by carbon capture. This ...
  • 1,001
3 votes

Which is more energy efficient? Heating ten 1L water separately or one 10L water directly

A. It's energy efficient to boil exactly that amount of water which is actually needed for tea preparation. To heat more water means some water is not used and heat will be wasted into the air. B. ...
  • 491
2 votes

Measure and compare energy consumption

tldr: Look at power rating of different appliances (show in W or kW typically), or most simply try to buy Energy Star appliances. The first thing that you should know is that if you are trying to be ...
2 votes

Do USB outlets waste energy just like conventional wall warts?

I was looking for similar information and came across this article: "Tested: Should You Unplug Chargers When You’re Not Using Them?". Seems that, while some of the wall warts may draw more power, ...
  • 21
2 votes

How many grams of CO2 are emitted to produce one paper napkin?

I found a few different references for this: 10 g CO2e per paper towel (from the Guardian, 2010) 10 g CO2 per paper napkin (from Treehugger, 2009) 7.3 g CO2e per virgin paper towel (from MIT/Dyson ...
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2 votes
Accepted

Is an incrementalist approach to decarbonisation feasible?

tldr: yes, with sufficient political will, an incremental approach is sufficient - we could decarbonise our energy consumption in 20 years. There are still a lot of unknowns (like just what we do ...
  • 14.7k
2 votes

How can I figure out what's using so much electricity in my home?

For the daily energy consumption quoted, optimizing the lights will not make a significant dent. I know because I've been there. Keep in mind that large loads (electric stove, electric drier, heaters, ...
1 vote

How can I figure out what's using so much electricity in my home?

About the graph showing the changes along the week, I suggest you to take a list of the domestic appliances that consumes more eletricity (like this ), to sort them by energy consumption rate, and to ...
  • 186
1 vote

How much energy does it take to store 1 Terabyte of data in the cloud?

The open-source project Cloud Carbon Footprint estimated the carbon footprint of storing 1TB in the Cloud. In their methodology they explain that they use the following numbers: HDD average capacity ...
  • 14.3k
1 vote
Accepted

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

I went down a few rabbit holes to figure this one out -- ultimately the search that got me going the right direction was "estimate savings on heating bills from adding insulation". The first few ...
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Only top scored, non community-wiki answers of a minimum length are eligible