11

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 the switch is on. In that case the light will use a (very small) amount of power.


7

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 some models, and a built in web server on the high end one. The high end one can be made to work over wireless with an adapter. The USB only versions could be used ...


7

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 people to boil the one cup of water they actually want, and that has worked reasonably well. If you can make 10 litres of boiling water and insulate the container ...


7

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 lights are on 8-10 hours a day is probably a good idea. Replacing the lights in the hall closet that runs 20 minutes a week is not. Replace the lights in the ...


7

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 have very fancy modern power-efficient desktops that can use less than 20W idling, or it may have six year old power-hungry behemoths that use well over 100W ...


7

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 they may be at the very cheap end. This will be a matter of safety regulations, but the cheapest designs fall down on safety and efficiency. I hunted for one ...


5

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. Let's make some assumptions: You have three mobile phones in your household. Each phone has a battery with a capacity of 2Ah (2000mAh) at 5V One of these ...


5

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 will be higher during boiling, so it will take more energy. However, once boiled, it will then lose energy. So if you're boiling water for consumption many hours ...


4

"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 harnessing one's body energy for external power consumption purposes?" I feel like this one question you asked fairly neatly sums up your entire overall question. ...


4

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 meter per day ~= hours of equivalent full power sun. You'll see that Houston average about 4 kWh/m^2/day. That means that an eg 20 W panel will produce about 4 ...


4

To answer this portion of your question: "But what other ways can one use one's own body energy wisely, and in general what principles / themes can one explore to put it into practice? " You made mention of using your body for transportation but you can go beyond just transportation. You can use peddle power or a rowing machine to power your cell phone, to ...


4

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 required. Imagine that your house is in a steady state, using the same amount of power, with a steady mix of fuel being used to generate that power. When you ...


3

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 / year. These numbers are much closer to the low figure than the high one given in the question. We can also see that larger drives use proportionally less power ...


3

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


3

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. But if you need to prepare for example 5 liters of the tea at once, it is more effective to heat it at once, and not to heat it 5 times 1 liter, due to ...


2

I see the human body as an energy consumer rather than producer. I would agree that controlling your diet (quantity and quality) will have energy benefit on the overall system by making him run smoothly and more efficiently, so that will be a definite gain of energy, but not a way to harvest the body energy. To simply exercise is I think a waste of energy, ...


2

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 ignore those — because they will clearly self-terminate — and just look at the cryptos that don't require huge amounts of energy to exist, then we've got a more ...


2

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 as sustainable as possible the manufacture of the products must be considered. If the appliance has a short life or low energy consumption throughout its life ...


1

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, modern ones use almost nothing. Probably not worth buying anything fancy to address the "problem".


1

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 results there are helpful. Ultimately, this calculator provides the answers you're looking for: "Home Heat Loss Calculator" from Build it Solar. Designing for a ...


1

If you are currently living there then you can work it out based on your energy bill. It is difficult to estimate how much energy would be used on ** heating** the house as it can vary widely, depending on how the house was built and your preferences (how long you have it on for). Average energy usage in Wyoming is 894 kWh Per Month, but that is averaged ...


1

First, how do we look at the biogas yield of a suvbstrate? We look at the total solids (TS) and volatile solids (VS), and then measure the gas production per VS. TS is the fraction that remains after thorough drying, while VS is the fraction that is lost after heating the dry stuff to a few hundred °C for an hour or so. VS is a handy stand in for the part of ...


1

Yes, you could. Biogas production is heavily depending on outside factors. If you have to haul the matter a significant distance, you may end up with a net loss. Biogas overall is a way to intercept some energy that would otherwise be lost. Remember too, that biogas is mostly methane. If your system leaks, then you are replacing the CO2 that the ...


1

Foregon, I don't know where you are, but where I live, conserving body heat (especially at night) can be a big contributor towards reduced fossil fuel consumption. Many homes are heated with fossil fuels (or with wood that might otherwise be left standing). Given that we have to eat and produce ~100 W waste heat anyway, why not use that heat to remain ...


1

My body produces sometimes a huge amount of energy False. Even a very active person typically doesn't need to consume more than 3,000 kcal a day. This is equivalent to about 3.5 kilowatt hours. This is equivalent to the average solar insolation over about 4 square feet (not considering weather), or 1/10th a gallon of gasoline. It's not a particularly ...


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