Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [energy]

the sustainable use of energy, through efficiency and renewables. Use this tag for questions on energy in general. For questions on a specific energy type see [electricity], [heating] or [light]. For questions specificially about efficiency, use [energy-efficiency]

30
votes
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 ...
62
votes
10answers
12k views

What is an energy efficient way to get fresh air indoors during winter?

Letting some fresh air inside is always a good idea, but during the winter it seems a bit wasteful to fling open the window and let the fresh air in at the expense of all that hot air going out, and ...
16
votes
2answers
6k views

How can I get my landlord to install better insulation?

We live in an apartment that has a lot of gaps in the doors and windows and poor insulation in the walls. Is there a way to make the landlord fix this? Some sort of property codes or something? He ...
3
votes
2answers
66 views

What is marginal energy?

I answered to a question and used the term "marginal energy". The answer wasn't understood by all, so I'm going to expand on the term to illustrate how it works. So, what is marginal energy?
22
votes
4answers
771 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 ...
42
votes
6answers
827 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 ...
34
votes
2answers
559 views

What’s the best strategy for turning off CFLs that will save energy but not reduce lifespan so much

With ordinary bulbs, I was used to turning the lights off even when I left the room for a few minutes (mostly because I know that I'll find other business and forget to return :-) ), but I've heard ...
28
votes
4answers
133k views

Which type of portable electric heater is better?

When one is buying a portable electric heater, there are at least three different types available: Radiative halogen heaters Fan heaters Oil-filled radiators and similar Images of examples of each ...
29
votes
9answers
18k views

What to do with old, unused incandescent light bulbs

Over the years, my family has built up a small stockpile of incandescent light bulbs. More recently, we have been replacing our incandescent lights with more energy-efficient alternatives. ...
25
votes
4answers
7k views

Is there a difference in insulation to keep heat in or out?

I know that one of the best ways to save energy at home is insulation. The question is, is there a different method for keeping the heat in when it's cold and keeping the heat out when it's warm? I ...
22
votes
2answers
172 views

Do “100% renewable” electricity plans increase renewable electricity production?

In the advertising for this year's earth hour in Sydney, Australia, it encourages people to switch from conventional electricity to renewable energy. A number of electricity providers offer "100% ...
15
votes
3answers
331 views

Best way to dry hands

In our office toilets at work we have paper towels and a hand dryer. Is it better for the environment to use the towels or the dryer?
4
votes
1answer
463 views

Can pumped water energy storage be combined with rainwater harvesting?

A recent question on what to do with harvested rainwater got me thinking about pumped energy storage systems. Since both systems require storage of water for later use, is there a cost-effective way ...
25
votes
5answers
4k views

Does a dishwasher save water in the long term?

I've been considering a dishwasher, but there are a range of different opinions on if they save water (or even energy) or not. Do we have any sources one way or the other?
19
votes
2answers
3k views

Meat or fish, which requires more energy to produce?

In general it is assumed that the energy that is required to produce a certain type of food is a good surrogate for the total environmental burden of food products. I scanned some studies to compare ...
15
votes
1answer
144 views

Does transporting plastic offset the benefits of recycling it?

Apparently China has been processing about half the world's waste until this year, and most of that waste is transported over the ocean in large container ships. Recycling plastic uses less energy and ...
21
votes
4answers
138k views

Leaving the oven door open for heat - bad idea?

I've heard before that it's a bad idea to use an oven to heat your house, because it's inefficient and carries the risk of carbon monoxide poisoning. But what about leaving the oven door open after I'...
21
votes
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 "...
17
votes
5answers
799 views

What is worse: Wasting water or energy?

I am currently trying to buy a dish washer and just got a washing machine lately and I am really confused whether it is better to buy a machine which uses less water or one which uses less energy. ...
10
votes
2answers
2k views

How much energy does it take to create a single light bulb?

This question is a part of this question. Perhaps it is better suited on the physics SE, but here goes. I would like to know how much energy it takes, in the modern world, to construct an ordinary, ...
17
votes
1answer
145 views

Long-term sustainability concerns of compact flourescent vs incandescent light bulbs

There is a strong movement to push people away from using incandescent lightbulbs in favor of compact flourescent bulbs in order to save energy, but the pollution profiles of these bulbs are very ...
15
votes
3answers
212 views

How can I determine whether roof top wind turbines would be beneficial in my area?

Rooftop wind turbines seem great in principle, but in practice, especially in urban areas their usefulness and efficiency is debated, such as in this article. The most general consensus seems to be ...
5
votes
2answers
83 views

Sustainability of wood pellet sources for biomass boiler

We're considering a biomass boiler for our guesthouse (1820 vintage with corresponding energy issues). The opportunity to reduce gas usage and the economics of the RHI scheme in the UK (a sort-of ...
11
votes
2answers
201 views

Should I replace existing inefficient light bulbs?

Similar to this question (except that's about cars), if I can buy more efficient light bulbs than the ones I'm using right now, should I? Or is it better to wait until my current light bulbs expire, ...
9
votes
4answers
3k views

Is gasoline or Diesel refining less sustainable, per energy output?

Inspired by my own answer here, I'm wondering what the actual numbers are regarding gasoline and Diesel fuel refining. I have read (don't remember where) that refining of Diesel fuel is less ...
8
votes
3answers
150 views

Is pellet fuel a sustainable energy source in the way it's used now?

Pellet fuel is considered a sustainable energy source. But the way it's used now seems to produce air pollution which I think should not happen in case of sustainable energy source. So is pellet ...
6
votes
1answer
102 views

Does bio jet fuel have a positive energy balance?

This article which was recently trending got me thinking about biofuels: Alaska Airlines makes first flight using jet fuel made from trees. I am not familiar with the numbers for biodiesel, but I ...
5
votes
1answer
68 views

Is there an “energy returned on materials invested” index for energy sources?

We already try to measure how much energy is invested (EROEI) in the production of energy, but I have a hard time finding numbers on the materials invested. For example: What is the total energy a ...
3
votes
3answers
778 views

Is 3 phase electrical generation more efficient to utilize than single phase?

Is 3 phase power more efficient to generate/use? How difficult or complicated is it going to be to provide balanced single phase load(s) from a 3 phase service? (equipment & controls required) If ...
3
votes
1answer
101 views

How long will a 12V Koolatron compact cooler last with 12Ah battery?

I'm thinking of purchasing a Koolatron P20 compact cooler and this ExpertPower 12200 battery How long will cooler last with this battery at full charge? Is this the correct battery to use for this? ...