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48

There are a lot of little things you can do that can add up. Here a some suggestions: Wash clothes in cold water only. Turn your freezer/refrigerator up a few degrees. Purchase insulated curtains/shades, and close them during the day when you are at work. Make sure your furniture is arranged so that it is not blocking any vents or radiators. Purchase a ...


43

Good ventilation needs a strategy of its own accord. It doesn't just happen. It will depend on what climate zone you're in, and what your building is, but from your question, I'm going to assume that winter means you're having to use some space-heating to get the home to a decent temperature. The very best ventilation strategy we have, is to make sure that ...


32

Open all windows wide but only for a short period. It will replace the air, but won't cool down the walls. This is the usual recommendation of gas companies.


24

In reality, yes, it probably does matter. In each case, it will depend on a lot of detail, so I'll discuss the theoretical concepts, rather than any one particular application. How heat is lost Heat moves about through a combination of three ways. One, two or all three might be significant in any particular case. convection - the movement of hot air to a ...


24

I disagree that dishwashers, compared to hand washing, will not save energy. First of all, as with almost anything, it depends how it's done. If you run your dishwasher half full, that's going to be bad for energy and water use. Similarly, if you hand wash, with the hot water running the whole time, that's bad. So, either technique requires tuning the ...


23

If you want to be more energy efficient in your apartment, you should look to the past. How were people living before? There are quite different living patterns in big cities and in small cities or villages. When I first came to a big city and I was living with other people, I was shocked how much water was used! The average usage of 6 cubic meters per ...


23

I use PVGIS calculator to estimate photovoltaics energy gain to my satisfaction. It contains realistic Europe and Africa weather data. Although this would be only a far estimate, let's assume you face south and you're based in Rome, Italy (instead of Chicago, IL), and we get: a maximum of 1260 kWh a year with an optimal inclination of 34° and almost south ...


22

Mythbusters featured lightbulbs on Episode 69. The conclusions they came to were There is no appreciable lifespan impact from turning them off and on There is no cost savings from leaving them on to "warm up" Edit, FTFA: Bulb Longevity They tested one final element of this myth: frequently turning lights on and off decreases their life span, thus ...


20

Take a look at a passive solar heat collector. They work on the principle of thermosiphoning. The design in the link and the picture below has an additional top vent exposed to the outside so you can close the top interior vent and draw air out of the building during the summer. I've seen more advanced designs that include doors that automatically close at ...


19

General principles The important thing here is to realise what these heaters heat. Radiative heaters radiate infra-red light which strikes objects and heats them directly, heating the intervening air less. Fan heaters primarily heat the air in the room by forced convection. Oil filled radiators, work like ordinary central heating radiators, primarily ...


18

Water takes energy to pump, filter and treat (and the treatment chemicals require energy to make), so it's likely a substantial part of the water cost goes to energy anyway. Given that in your case you can save a massive proportion of water for very little extra electricity, I'd go with the water saving. Secondly, it's often possible to run a lower ...


17

Although there is a definite allure to generating your own energy on-site, if you do not have good solar access then it is hard to get around that reality. Instead, there are other ways to have renewable energy captured on your behalf: If you have a choice of energy suppliers, buy 100% wind or solar generated energy. Look into group solar. Perhaps you ...


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

From http://www.treehugger.com/green-food/meat-eaters-guide-get-to-know-the-carbon-footprint-of-your-diet-lamb-beef-cheese-are-the-worst.html we have which I find pretty fascinating — certainly I would have put pork much closer to beef than either salmon or Turkey... really interesting stuff. I'd like to see as well the same graph but per calorie rather ...


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 ...


16

TLDR; don't use them for lighting. Given that you could keep your incandescent bulbs for when your current energy-efficient (I will assume CCFL) bulbs need replacing, your choice boils down to: buy a new CCFL; or use an incandescent that has already been manufactured. This helpful analysis gives the embodied energy in a CCFL as 1.7 kWh. Let's assume that ...


15

Use the kettle if you have one, and if you're nearby, switch it off as soon as it boils. Here's some evidence to prove it's the best option: Method: Measure 252g of cold tap water into Frog Mug using electronic kitchen scales, being the amount I'd use to make a cup of tea. Temperature according to my thermometer is 18 degrees C. Plug microwave in through ...


15

I'll take a slightly different line to Mark Booth's excellent answer. fan heater: If you've got a lot of still air, and / or if you only want the heater on for short bursts, then the fan heater is probably best, because it will get the warm air circulating in the room, and it will respond quickly to being turned on and off. However, dust can settle on the ...


14

You don't state how much change you are willing to consider. A device called a Heat Recovery Ventilator (HRV) passes the outgoing air and the incoming air through a heat exchanger and transfers the heat from one to the other. It usually would be connected to your central air ducts to distribute the incoming air, and would require pass-throughs for the ...


14

This is the classic agency-dilemma,or principal agent problem. THe one who should bear the cost, the landlord, doesn't see any immediate benefit; and any indirect benefit may be, or be believed to be absent. The landlord should bear the cost because, at least in theory, in a well-functioning market, a landlord would be able to earn higher rent on a well-...


13

Do “100% renewable” electricity plans increase renewable electricity production? Well, it will depend on how the specific scheme is implemented, what the renewable suppliers are, and what timescale you are considering. So, the answer could be yes, no or maybe. I don't know about your supplier's particular plan, and in order to keep this answer useful to as ...


12

The most common automatic light switch is a PIR sensor. I've looked up technical parameters of several such sensors. The idle (sensing) power consumption of most of them is 0.1 W. Some of them have the idle power consumption of up to 0.3 W and I believe some older ones could consume even 1 W. The active power consumption of the sensor is higher, but it's ...


12

Both incandescent and fluorescent are quite old technologies, and have been bettered in terms of efficiency and lifecycle impact. Furthermore, compact fluorescents aren't the only type of fluorescents. So although the compact fluorescents are superior to incandescents anywhere with a high-carbon marginal electricity supply (so almost all the world, in 2013, ...


12

TLDR; cadmium telluride panels have the highest EROI of the mentioned PV panels (around 34.2) EROI estimates vary widely. This is because of differences in the method of calculation, scope of the study, installation location, assumed lifespan of a panel, etc. This also makes it relatively easy to manipulate EROI calculations. Pessimistic The most ...


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

Someone has done it. A majority of the electricity I buy comes from geothermal energy †. Of course, I live in the Pacific Northwest of North America, which puts me close to a tectonic plate boundary. This presents good conditions for extracting geothermal heat (since the earth's crust is thinner at such boundaries ... making shallower wells ...


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

I use them in garden/indoor. Something like this... (source : google search)


11

I live off-grid, so I did a lot of study on this topic. All used coffee grounds make good fertilizer. Drip machines seem to use a lot of energy, and they seem to use it for a lot of time. They also use disposable filters. Drip machines are kind of on the off-grid "blacklist". Percolators waste a lot of energy because they have to keep the water boiling ...


10

There is an empirical measure. Install a small weather station device and record the wind conditions. Then you can compare your charts to what turbine vendors promise and see how much of the time you have enough wind for the turbine to be useful.


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