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16

Efficiency The inefficiency you're referring to is probably not the efficiency with which the gas is burned (a separate issue), but instead is likely to be because the air heated by an oven does not mix well with air in the room, so convection causes it to rise straight to the ceiling. This doesn't tend to make a cold house feel much warmer (especially if ...


16

Perhaps this article is what you are looking for? It's a study by the US Department of Energy on the life-cycle environmental and resource costs in the manufacturing, transport, use, and disposal of light-emitting diode (LED) lighting products in relation to comparable traditional lighting technologies. There is a similar study done by manufacturer ...


15

It can be possible using drying piece of sample wood, Dry pieces of wood in the oven or in another way . Make sure that pieces should be well cut. Logs have varying moisture contents, depending on tree age, time since felling and position in the seasoning pile. The moisture content also varies from the middle of the log to the ends. You should use 3 to 5 ...


15

There are two main categories to consider here. The first is to improve the efficiency of how your home is kept warm - either by increasing the efficiency of the heating system, or by reducing the rate at which warmth is lost to the outside. If your home is quite "leaky" then major gains can be made this way quite cheaply. Other answers to this and other ...


14

Operating one cooking appliance would be more efficient. Using your two-pot method, to maintain the boiling water once it is transferred to the cooking pot, you'll have to first bring that cooking pot up to temperature. During that time, the system inefficiencies are in effect for two systems, and heat and energy are being lost. The heat being radiated ...


13

It's correct that the production of 1 ceramic mug requires much more material and energy than the production of 1 plastic cup, but this isn't a fair comparison. Plastic cups are generally used once or perhaps twice and then disposed of. A ceramic mug is likely to be used several hundreds of times before it breaks and is thrown away. Let's assume you use a ...


12

A: Insulate your attic. This can be done in an afternoon. Put 12-16" total in that space. B: Seal the leaks: Weatherstrip the doors and openable windows. All electrical outlets are punctures in the outside wall. You can buy gaskets for them, or you can make them out of the styrofoam meat trays you get from the grocery store. C: Heat shrink ...


11

There isn't a single reliable way that fits all circumstances. What we can do, is look at some of the factors that influence the pros and cons. Uncertainties within the green electricity tariff If it was absolutely clear that some of the money you spend on electricity goes to increasing the amount of renewable energy going into the grid, then that would ...


11

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 bulbs. the report THelper♦ cited has the following bar graph that pretty much answers the question:


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.


11

Generally, it makes sense to save power, even during the winter. The difference between space heating and waste heat The main difference between home heating systems and waste heat from electrical appliances is the way the heat is released, and where it's released. Many types of home heating systems are designed to provide heat in a specific way, such as a ...


10

There is a presentation comparing the environmental impact of different vegetable oils here (direct download link to pdf!). It is shown that olive oil has less impact regarding the output of greenhouse gases and substances that contribute to acidification, eutrophication and the generation of photochemical smog though it requires more space to grow it. The ...


10

You've pictured a disposable plastic cup. If you assume that you can use it a few times, then you might consider that you get through one a day. A ceramic cup lasts until you drop it. The cup in your photo is only for cold drinks anyway. Paper or expanded polystyrene are usually used for hot drinks. This link runs the numbers: In summary, ceramic is best. ...


9

First, given that the heat has to go somewhere, I dont think you will get more heat transferred usefully to your house from opening the oven door. You may get less for the reason that the hot air may rise as a mass (rather than trickling out) and thus have less impact on the rest of the air. As some of the others have said the issue efficiency-wise will ...


9

Ultimately, it is a question of system boundaries. To be sustainable, a process must not ... Use energy faster than it can be replenished Use material resources faster then they can be replenished. Note that you could see most forms of energy also as material (fuel) Pollute faster than the polluted system can clean itself. Note that most energy generation ...


9

Since this is a part of the defining sustainability series, I am adding my own perspective here. Other perspectives of course are welcome and the whole purpose is to provide public insight into what's on and off topic here so please vote on these. The problems @Pitt noted above are design issues with well understood solutions, which include biodiversity ...


8

Yes, it matters, a little, but it also depends on your location. In your car, the process of converting fuel to movement is pretty inefficient (about 25% to 30%, according to this). That movement (kinetic energy, if you're a physicist) is then converted to electrical energy with an efficiency of 75% to 80%, giving you an overall efficiency of 18.75% to 24%. ...


8

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 time, one before the night, one after it. Let's choose them so that the dwelling has the same amount of heat energy contained within it at each point, so all the ...


8

The stabilisation energy rate will be exactly exactly equal to the rate at which energy is lost. Assuming the tank is closed, so there are no evaporative losses, there are two other ways energy is lost. Firstly, from conductive losses through the surface of the tank. That will depend on the thermal conductivity of the tank, and on difference between the ...


7

You measure the temperature of the water going in to the solar panel, and the temperature coming out, and the rate of flow through. The power produced is then a simple calculation of multiplying the specific heat capacity of water, by the rate of flow, by the difference between return and flow temperatures. The energy produced is the integral of power over ...


7

As for federal tax credits, I believe they only apply to 'principal residence' so you must both own and live in it. However the landlord may be able to write it off as a cost if she pays the bill, for some relief. Check the energystar.gov site for details on what qualifies for tax credits: http://www.energystar.gov/index.cfm?c=tax_credits.tx_index . ...


7

One of the key considerations here is how much time the appliance will spend turned on. If an old CRT TV is hardly used, then the environmental footprint of continuing to use it is very low, even if it uses 5 times as much electricity as an LCD one. Secondly, the way the electricity is generated makes a substantial difference. If renewable energy is used to ...


7

I think a "general principle" is that "express wash" usually means one or more of the following reduce the wash cycle reduce the spin cycle skip a rinse cycle (e.g. by not using any softener) etc. In other words, rather than "same washing in less time" you get "less washing", but still enough for not-so-dirty clothes to get clean. This means that the ...


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

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

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 Wikipedia, polyethylene is the most common type of plastic. There are three main categories of polyethylene (also from Wikipedia): PET (polyethylene terephthalate), ...


6

Space heaters (yes, even those fancy quartz ones) use electric resistance to generate heat. If your home's HVAC system is switching to resistance heating when it's cold outside, replacing it with space heaters should, in an ideal world, neither increase nor decrease your energy usage. If you drop the whole house temperature by 5 degrees and use a weak space ...


6

There's various options depending on the level of accuracy desired. To be most useful to a general audience, not just this question's asker, I'll mention a couple rough methods: The way you should track your energy choices in general is fairly simple: monitor your energy bills monthly, before and after making the change (in this case, before and after ...


6

A Smart Meter that is compatible with PlotWatt will be able to tell your step-dad exactly how much each appliance in the house is using. Even without PlotWatt, a smart meter like the TED 5000 can be interesting for a few exercises: try to turn everything in the house off and see how much energy is still being consumed. As you turn things off, check and ...


6

As I understand it, in the scenario that you describe, the heat pump is not doing anything useful, and the question simply boils down to "Is it best to use a resistive electric heater through a central heating system, or to use radiative (infra-red) heaters in the rooms that are occupied". That's quite a simple one to answer: Either system is 100% efficient ...


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